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Hurricane Hugo

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274-571: Hurricane Hugo was a powerful tropical cyclone that inflicted widespread destruction across the northeastern Caribbean and the Southeastern United States in September 1989. The eleventh tropical cyclone , eighth named storm , sixth hurricane, and second major hurricane of the 1989 Atlantic hurricane season , Hugo arose from a cluster of thunderstorms near Cape Verde on September 10, 1989. This cluster coalesced into

548-733: A C-141 airlifter with government relief workers and communications equipment to Saint Croix. The demographics of the Virgin Islands a year after Hugo reflected the hurricane's impact: roughly 10% of Saint Croix's populace did not return to the island within a year of Hugo. A smaller exodus occurred at Saint Thomas and Saint John. Three days after the storm hit, the Governor of the United States Virgin Islands Alexander Farrelly asked President Bush for federal assistance in restoring order to

822-531: A Tropical Cyclone Warning Centre by the World Meteorological Organization 's (WMO) tropical cyclone programme. These warning centers issue advisories which provide basic information and cover a systems present, forecast position, movement and intensity, in their designated areas of responsibility. Meteorological services around the world are generally responsible for issuing warnings for their own country. There are exceptions, as

1096-452: A front . However, some kind of cloud forcing , whether it is a front, shortwave trough, or another system is needed for the air to rapidly accelerate upward. As the warm, moist air moves upward, it cools, condenses , and forms a cumulonimbus cloud that can reach heights of over 20 kilometres (12 mi). As the rising air reaches its dew point temperature, water vapor condenses into water droplets or ice, reducing pressure locally within

1370-704: A tropical depression and strengthened into Tropical Storm Hugo as it tracked west across the Atlantic Ocean for several days. On September 13, Hugo became a hurricane and continued to intensify through September 15 when its sustained winds peaked at 160 mph (255 km/h), making it a Category 5 hurricane on the Saffir–Simpson scale . Between September 17 and 21, Hugo made landfall on Guadeloupe , Saint Croix , Puerto Rico , and lastly South Carolina , with major hurricane strength winds. The storm weakened inland and accelerated north over

1644-416: A 1.5 degree warming lead to "increased proportion of and peak wind speeds of intense tropical cyclones". We can say with medium confidence that regional impacts of further warming include more intense tropical cyclones and/or extratropical storms. Climate change can affect tropical cyclones in a variety of ways: an intensification of rainfall and wind speed, a decrease in overall frequency, an increase in

1918-444: A 2019 review paper show a future increase of rainfall rates. Additional sea level rise will increase storm surge levels. It is plausible that extreme wind waves see an increase as a consequence of changes in tropical cyclones, further exacerbating storm surge dangers to coastal communities. The compounding effects from floods, storm surge, and terrestrial flooding (rivers) are projected to increase due to global warming . There

2192-497: A Category 4 hurricane with sustained winds at 140 mph (230 km/h). This made Hugo the strongest hurricane to strike Guadeloupe since a hurricane each in 1899 and 1928 . A minimum air pressure of 941.1 mbar (hPa; 27.79 inHg) was recorded at La Désirade and 943 mbar in Raizet , with a 97-mile-per-hour (156 km/h) wind gust documented in the last weather observation transmitted from Pointe-à-Pitre . A ship in

2466-651: A T0 for extremely weak tornadoes to T11 for the most powerful known tornadoes. Doppler radar data, photogrammetry , and ground swirl patterns (cycloidal marks) may also be analyzed to determine intensity and award a rating. Waterspouts have similar characteristics as tornadoes, characterized by a spiraling funnel-shaped wind current that form over bodies of water, connecting to large cumulonimbus clouds. Waterspouts are generally classified as forms of tornadoes, or more specifically, non- supercelled tornadoes that develop over large bodies of water. These spiralling columns of air frequently develop within tropical areas close to

2740-613: A circle, whirling round their central clear eye , with their surface winds blowing counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere . The opposite direction of circulation is due to the Coriolis effect . Tropical cyclones tend to develop during the summer, but have been noted in nearly every month in most tropical cyclone basins . Tropical cyclones on either side of

3014-1154: A flash flood. In Burnsville, North Carolina , flooding prompted the evacuation of 79 prisoners. Rainfall totals of 1–4 in (25–102 mm) occurred throughout southwestern Virginia, with a maximum of 6.5 in (170 mm) in Hillsville, Virginia . Some low-lying areas and streams flooded, including the New and Roanoke rivers; flooding along the South Fork of the Roanoke forced about 60 people to evacuate. Strong winds in Georgia downed trees in four counties, damaging homes and power lines. About 50–75 trees were toppled around Savannah , where wind gusts reached 54 mph (87 km/h). The city's weather service office recorded 6.10 in (155 mm) of rain. Winds of 45–50 mph (72–80 km/h) downed trees in Mercer County, West Virginia . Flooding forced

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3288-405: A flow of warm, moist, rapidly rising air, which starts to rotate cyclonically as it interacts with the rotation of the earth. Several factors are required for these thunderstorms to develop further, including sea surface temperatures of around 27 °C (81 °F) and low vertical wind shear surrounding the system, atmospheric instability, high humidity in the lower to middle levels of

3562-703: A full evacuation, with 175,000 leaving their homes and 6,000 moving to public shelters. Civil authorities in Glynn County, Georgia , urged the 15,000 residents along barrier islands to begin evacuating on the morning of September 21 ahead of hurricane warnings. Public schools were closed in Chatham County, Georgia , to allocate school buses for the evacuation of barrier islands. Three shelters were opened in North Carolina, though emergency management did not anticipate ordering evacuations. Hugo

3836-597: A helicopter and a crew of 100 sailors that aided in cleaning up roads between Plymouth and W. H. Bramble Airport. Extensive effort was required to clean up Montserrat's roads due to the prevalence of debris. Along with the crew of the Alacrity , the Barbados Defence Force and Jamaica Defence Force also assisted in road cleanup operations in Montserrat. The International Rescue Corps maintained

4110-404: A high frequency for cloud-to-ground lightning, like Florida, lightning causes several fatalities per year, most commonly to people working outside. Acid rain is also a frequent risk produced by lightning. Distilled water has a neutral pH of 7. "Clean" or unpolluted rain has a slightly acidic pH of about 5.2, because carbon dioxide and water in the air react together to form carbonic acid ,

4384-506: A higher intensity. Most tropical cyclones that experience rapid intensification are traversing regions of high ocean heat content rather than lower values. High ocean heat content values can help to offset the oceanic cooling caused by the passage of a tropical cyclone, limiting the effect this cooling has on the storm. Faster-moving systems are able to intensify to higher intensities with lower ocean heat content values. Slower-moving systems require higher values of ocean heat content to achieve

4658-411: A kilometer across. One of Kermit 's four engines overheated within the hurricane's eyewall , prompting its shutdown that caused the plane to quickly lose altitude as it entered the eye. The pilots regained control when the plane reached an altitude of 790 ft (240 m) at 17:28 UTC. To avoid overworking the three remaining engines, the pilots orbited the center of Hugo for an hour within

4932-464: A large number of forecasting centers, uses infrared geostationary satellite imagery and an algorithm based upon the Dvorak technique to assess the intensity of tropical cyclones. The ADT has a number of differences from the conventional Dvorak technique, including changes to intensity constraint rules and the usage of microwave imagery to base a system's intensity upon its internal structure, which prevents

5206-464: A large role in both the classification of a tropical cyclone and the determination of its intensity. Used in warning centers, the method was developed by Vernon Dvorak in the 1970s, and uses both visible and infrared satellite imagery in the assessment of tropical cyclone intensity. The Dvorak technique uses a scale of "T-numbers", scaling in increments of 0.5 from T1.0 to T8.0. Each T-number has an intensity assigned to it, with larger T-numbers indicating

5480-500: A local thunderstorm. During a thunderstorm, pollen grains can absorb moisture and then burst into much smaller fragments with these fragments being easily dispersed by wind. While larger pollen grains are usually filtered by hairs in the nose, the smaller pollen fragments are able to pass through and enter the lungs, triggering the asthma attack. Most thunderstorms come and go fairly uneventfully; however, any thunderstorm can become severe , and all thunderstorms, by definition, present

5754-458: A more damaging surge event from occurring. Saint-François was largely destroyed, with nearly half of houses remaining. Several tourist hotels there sustained heavy damage. Two people were killed in Le Moule , that been damaged at nearly 80 percent. The entirety of Guadeloupe's banana crop and most of its coconut palms and sugar cane crops were ruined by Hugo. The storm also wiped out most of

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6028-426: A much smaller area. This replenishing of moisture-bearing air after rain may cause multi-hour or multi-day extremely heavy rain up to 40 km (25 mi) from the coastline, far beyond the amount of water that the local atmosphere holds at any one time. This in turn can lead to river flooding , overland flooding, and a general overwhelming of local water control structures across a large area. A tropical cyclone

6302-534: A nearly 50-mile-wide (80 km) corridor of downed trees and power lines west of Charlotte , and hurricane-force wind gusts extended 200 mi (320 km) inland. The control tower at Charlotte Douglas International Airport clocked a 99 mph (159 km/h) gust, forcing personnel in the airport's control tower to evacuate. Windows were blown out of skyscrapers in Downtown Charlotte . The 400-foot (120 m) tall WSOC-TV antenna collapsed onto

6576-493: A number of techniques considered to try to artificially modify tropical cyclones. These techniques have included using nuclear weapons , cooling the ocean with icebergs, blowing the storm away from land with giant fans, and seeding selected storms with dry ice or silver iodide . These techniques, however, fail to appreciate the duration, intensity, power or size of tropical cyclones. A variety of methods or techniques, including surface, satellite, and aerial, are used to assess

6850-616: A peak gust of 78 mph (126 km/h). Eleven people were killed in the Netherlands Antilles and caused $ 50 million in damage there. The damage toll in the British Virgin Islands exceeded $ 50 million, with the loss of at least half of the islands' agriculture. Around 30 percent of homes were unroofed. Power outages affected the British Virgin Islands. The Associated Press reported "numerous injuries" and "scores of homes destroyed" on Tortola ,

7124-532: A peak sustained wind of 104 mph (167 km/h) punctuated by a 120 mph (190 km/h) wind gust. At Luis Muñoz Marín International Airport, sustained winds reached 77 mph (124 km/h), gusting to 92 mph (148 km/h). The heaviest rain from Hugo in Puerto Rico occurred in the northeastern part of the island due to the hurricane's trajectory and orographic lifting induced by El Yunque . A peak rainfall total of 17.60 in (447 mm)

7398-422: A process known as rapid intensification, a period in which the maximum sustained winds of a tropical cyclone increase by 30  kn (56 km/h; 35 mph) or more within 24 hours. Similarly, rapid deepening in tropical cyclones is defined as a minimum sea surface pressure decrease of 1.75 hPa (0.052 inHg) per hour or 42 hPa (1.2 inHg) within a 24-hour period; explosive deepening occurs when

7672-444: A prominent feature and tracking it from scan to scan. A back-building thunderstorm, commonly referred to as a training thunderstorm , is a thunderstorm in which new development takes place on the upwind side (usually the west or southwest side in the Northern Hemisphere ), such that the storm seems to remain stationary or propagate in a backward direction. Though the storm often appears stationary on radar, or even moving upwind, this

7946-429: A remnant low-pressure area . Remnant systems may persist for several days before losing their identity. This dissipation mechanism is most common in the eastern North Pacific. Weakening or dissipation can also occur if a storm experiences vertical wind shear which causes the convection and heat engine to move away from the center. This normally ceases the development of a tropical cyclone. In addition, its interaction with

8220-499: A research experiment coordinated by the Hurricane Research Division . While penetrating the storm at an altitude of 1,500 ft (460 m), the plane encountered extreme turbulence and sustained winds of 190 mph (310 km/h), indicating a storm more intense than satellite estimates suggested. Flight data showed that the plane likely encountered a mesovortex comparable to a weak tornado spanning

8494-634: A result of high winds, power poles were toppled and tree branches fell, which caused most of New Brunswick's 15,000 power failures. In addition, several tree and signs were blown over in Saint John and Moncton. The storm also significantly affected the apple crop in New Brunswick. Strong winds were also reported in Newfoundland , with gusts recorded up to 43 mph (69 km/h). A plane bearing 60 rescue workers and emergency supplies

Hurricane Hugo - Misplaced Pages Continue

8768-582: A satellite communications link and provided support for 21 national and international organizations in recovery efforts. Rationing on petroleum was enforced, with a limit of four gallons (15 liters) per person. Waterborne illnesses in Hugo's aftermath proved fatal in Montserrat. A temporary hospital was established at the Montserrat Government House following the destruction of a recently completed hospital. President Bush declared

9042-581: A shelter. The storm surge accumulated within the Ashley , Cooper , and Santee rivers, forcing them over their banks and submerging low-lying areas 10 mi (16 km) upstream. One person was killed by the rise of the Cooper River at Mount Pleasant . Seven to eight hundred boats were left in derelict condition, and many in Shem Creek capsized. Hugo's surge spilled over The Battery and overtook

9316-680: A staging area for disaster response in the Caribbean due to its strategic position in the region and distance away from Hugo's forecast impacts. Several relief agencies had convened in Barbados earlier in 1989 to coordinate hurricane response plans. These agencies were mobilized ahead of Hugo's arrival in the Lesser Antilles. They were joined by additional teams from the United States Agency for International Development and

9590-569: A storm arises quickly and unexpectedly. Preparing the home by removing dead or rotting limbs and trees, which can be blown over in high winds, can also significantly reduce the risk of property damage and personal injury. The National Weather Service (NWS) in the United States recommends several precautions that people should take if thunderstorms are likely to occur: While safety and preparedness often overlap, "thunderstorm safety" generally refers to what people should do during and after

9864-569: A storm. Tropical cyclone scales , such as the Saffir-Simpson hurricane wind scale and Australia's scale (Bureau of Meteorology), only use wind speed for determining the category of a storm. The most intense storm on record is Typhoon Tip in the northwestern Pacific Ocean in 1979, which reached a minimum pressure of 870  hPa (26  inHg ) and maximum sustained wind speeds of 165 kn (85 m/s; 305 km/h; 190 mph). The highest maximum sustained wind speed ever recorded

10138-421: A storm. The American Red Cross recommends that people follow these precautions if a storm is imminent or in progress: The NWS stopped recommending the "lightning crouch" in 2008 as it does not provide a significant level of protection and will not significantly lower the risk of being killed or injured from a nearby lightning strike. Thunderstorms occur throughout the world, even in the polar regions, with

10412-581: A stronger system. Tropical cyclones are assessed by forecasters according to an array of patterns, including curved banding features , shear, central dense overcast, and eye, to determine the T-number and thus assess the intensity of the storm. The Cooperative Institute for Meteorological Satellite Studies works to develop and improve automated satellite methods, such as the Advanced Dvorak Technique (ADT) and SATCON. The ADT, used by

10686-405: A system has dissipated or lost its tropical characteristics, its remnants could regenerate a tropical cyclone if environmental conditions become favorable. A tropical cyclone can dissipate when it moves over waters significantly cooler than 26.5 °C (79.7 °F). This will deprive the storm of such tropical characteristics as a warm core with thunderstorms near the center, so that it becomes

10960-529: A tropical cyclone are a result of the conservation of angular momentum imparted by the Earth's rotation as air flows inwards toward the axis of rotation. As a result, cyclones rarely form within 5° of the equator . Tropical cyclones are very rare in the South Atlantic (although occasional examples do occur ) due to consistently strong wind shear and a weak Intertropical Convergence Zone . In contrast,

11234-688: A tropical cyclone is called a hurricane ( / ˈ h ʌr ɪ k ən , - k eɪ n / ), typhoon ( / t aɪ ˈ f uː n / ), tropical storm , cyclonic storm , tropical depression , or simply cyclone . A hurricane is a strong tropical cyclone that occurs in the Atlantic Ocean or northeastern Pacific Ocean . A typhoon occurs in the northwestern Pacific Ocean. In the Indian Ocean and South Pacific, comparable storms are referred to as "tropical cyclones". In modern times, on average around 80 to 90 named tropical cyclones form each year around

Hurricane Hugo - Misplaced Pages Continue

11508-461: A tropical cyclone's core has a negative effect on its development and intensity by diminishing atmospheric convection and introducing asymmetries in the storm's structure. Symmetric, strong outflow leads to a faster rate of intensification than observed in other systems by mitigating local wind shear. Weakening outflow is associated with the weakening of rainbands within a tropical cyclone. Tropical cyclones may still intensify, even rapidly, in

11782-401: A tropical cyclone's intensity or the direction it is traveling. Wind-pressure relationships (WPRs) are used as a way to determine the pressure of a storm based on its wind speed. Several different methods and equations have been proposed to calculate WPRs. Tropical cyclones agencies each use their own, fixed WPR, which can result in inaccuracies between agencies that are issuing estimates on

12056-501: A tropical storm. Bath and Bland counties registered 81-mph (130 km/h) gusts; these were the fastest gusts measured in Virginia in connection with the passing storm. As was the case in North Carolina, the winds downed numerous trees, causing widespread power outages and structural damage. Their arboreal debris obstructed hundreds of roads. Sporadic damage from Hugo occurred as far east as Interstate 95 . The damage toll in Virginia

12330-408: A two-digit number and suffix letter by the warning centers that monitor them. Thunderstorm A thunderstorm , also known as an electrical storm or a lightning storm , is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere , known as thunder . Relatively weak thunderstorms are sometimes called thundershowers . Thunderstorms occur in

12604-486: A type of cloud known as a cumulonimbus . They are usually accompanied by strong winds and often produce heavy rain and sometimes snow , sleet , or hail , but some thunderstorms produce little precipitation or no precipitation at all. Thunderstorms may line up in a series or become a rainband , known as a squall line . Strong or severe thunderstorms include some of the most dangerous weather phenomena, including large hail, strong winds, and tornadoes . Some of

12878-831: A typhoon. This happened in 2014 for Hurricane Genevieve , which became Typhoon Genevieve. Within the Southern Hemisphere, it is either called a hurricane, tropical cyclone or a severe tropical cyclone, depending on if it is located within the South Atlantic, South-West Indian Ocean, Australian region or the South Pacific Ocean. The descriptors for tropical cyclones with wind speeds below 65 kn (120 km/h; 75 mph) vary by tropical cyclone basin and may be further subdivided into categories such as "tropical storm", "cyclonic storm", "tropical depression", or "deep depression". The practice of using given names to identify tropical cyclones dates back to

13152-588: A voluntary evacuation order before the coast was placed under a hurricane warning, with the initial directive intended for barrier islands, beaches, and peninsulas outside Charleston. This was later supplanted by a mandatory evacuation order. Governor Campbell ordered eight coastal counties to open shelters; of these shelters, 20 were opened in Charleston County. Four hundred troops from the National Guard were activated to assist in evacuations along

13426-683: A weak acid (pH 5.6 in distilled water), but unpolluted rain also contains other chemicals. Nitric oxide present during thunderstorm phenomena, caused by the oxidation of atmospheric nitrogen, can result in the production of acid rain, if nitric oxide forms compounds with the water molecules in precipitation, thus creating acid rain. Acid rain can damage infrastructures containing calcite or certain other solid chemical compounds. In ecosystems, acid rain can dissolve plant tissues of vegetations and increase acidification process in bodies of water and in soil , resulting in deaths of marine and terrestrial organisms. Any thunderstorm that produces hail that reaches

13700-413: A week in some areas. At Carraízo Dam , San Juan's primary supplier of water, five electric motors in the pumping station were inundated, disrupting water distribution; replacement of these motors cost $ 200,000. The lake formed by the dam had begun to rise, and floodgates were rendered inoperable by power outages. Poor maintenance had left the dam vulnerable to a larger catastrophe; however, Hugo's rainfall

13974-465: Is a polar molecule that can carry a charge, so it is capable of creating the charge separation needed to produce lightning). These electrical discharges can be up to a thousand times more powerful than lightning on the Earth. The water clouds can form thunderstorms driven by the heat rising from the interior. The clouds of Venus may also be capable of producing lightning ; some observations suggest that

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14248-596: Is a complex of thunderstorms that becomes organized on a scale larger than the individual thunderstorms but smaller than extratropical cyclones , and normally persists for several hours or more. A mesoscale convective system's overall cloud and precipitation pattern may be round or linear in shape, and include weather systems such as tropical cyclones , squall lines , lake-effect snow events, polar lows , and mesoscale convective complexes (MCCs), and they generally form near weather fronts . Most mesoscale convective systems develop overnight and continue their lifespan through

14522-435: Is an illusion. The storm is really a multi-cell storm with new, more vigorous cells that form on the upwind side, replacing older cells that continue to drift downwind. When this happens, catastrophic flooding is possible. In Rapid City, South Dakota , in 1972, an unusual alignment of winds at various levels of the atmosphere combined to produce a continuously training set of cells that dropped an enormous quantity of rain upon

14796-415: Is assumed at this stage that a tropical cyclone has become self-sustaining and can continue to intensify without any help from its environment. Depending on its location and strength, a tropical cyclone is referred to by different names , including hurricane , typhoon , tropical storm , cyclonic storm , tropical depression , or simply cyclone . A hurricane is a strong tropical cyclone that occurs in

15070-406: Is calculated as: where p {\textstyle p} is the density of air, u {\textstyle u} is a sustained surface wind speed value, and d v {\textstyle d_{v}} is the volume element . Around the world, tropical cyclones are classified in different ways, based on the location ( tropical cyclone basins ), the structure of

15344-554: Is currently no consensus on how climate change will affect the overall frequency of tropical cyclones. A majority of climate models show a decreased frequency in future projections. For instance, a 2020 paper comparing nine high-resolution climate models found robust decreases in frequency in the Southern Indian Ocean and the Southern Hemisphere more generally, while finding mixed signals for Northern Hemisphere tropical cyclones. Observations have shown little change in

15618-414: Is cut off from its supply of warm moist maritime air and starts to draw in dry continental air. This, combined with the increased friction over land areas, leads to the weakening and dissipation of the tropical cyclone. Over a mountainous terrain, a system can quickly weaken. Over flat areas, it may endure for two to three days before circulation breaks down and dissipates. Over the years, there have been

15892-474: Is issued if a thunderstorm becomes severe, or will soon turn severe. In Canada, a rainfall rate greater than 50 millimetres (2 in) in one hour, or 75 millimetres (3 in) in three hours, is also used to indicate severe thunderstorms. Severe thunderstorms can occur from any type of storm cell. However, multicell , supercell , and squall lines represent the most common forms of thunderstorms that produce severe weather. A mesoscale convective system (MCS)

16166-556: Is known, then the total energy of a thunderstorm can be calculated. In a typical thunderstorm, approximately 5×10 kg of water vapor are lifted, and the amount of energy released when this condenses is 10 joules . This is on the same order of magnitude of energy released within a tropical cyclone, and more energy than that released during the atomic bomb blast at Hiroshima, Japan in 1945 . The Fermi Gamma-ray Burst Monitor results show that gamma rays and antimatter particles ( positrons ) can be generated in powerful thunderstorms. It

16440-525: Is little wind shear , the storm will rapidly enter the dissipating stage and 'rain itself out', but, if there is sufficient change in wind speed or direction, the downdraft will be separated from the updraft, and the storm may become a supercell , where the mature stage can sustain itself for several hours. In the dissipation stage, the thunderstorm is dominated by the downdraft. If atmospheric conditions do not support super cellular development, this stage occurs rather quickly, approximately 20–30 minutes into

16714-468: Is more of a factor with thunderstorms with heavy precipitation (HP) than with thunderstorms with low precipitation (LP). When thunderstorms merge, which is most likely when numerous thunderstorms exist in proximity to each other, the motion of the stronger thunderstorm normally dictates the future motion of the merged cell. The stronger the mean wind, the less likely other processes will be involved in storm motion. On weather radar , storms are tracked by using

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16988-741: Is not falling through the updraft) with a strong, rotating updraft (a " mesocyclone "). These storms normally have such powerful updrafts that the top of the supercell storm cloud (or anvil) can break through the troposphere and reach into the lower levels of the stratosphere . Supercell storms can be 24 kilometres (15 mi) wide. Research has shown that at least 90 percent of supercells cause severe weather . These storms can produce destructive tornadoes , extremely large hailstones (10 centimetres or 4 inches diameter), straight-line winds in excess of 130 km/h (81 mph), and flash floods . In fact, research has shown that most tornadoes occur from this type of thunderstorm. Supercells are generally

17262-412: Is one of the most significant thunderstorm hazards to aircraft. When hail stones exceed 13 millimetres (0.5 in) in diameter, planes can be seriously damaged within seconds. The hailstones accumulating on the ground can also be hazardous to landing aircraft. Wheat, corn, soybeans, and tobacco are the most sensitive crops to hail damage. Hail is one of Canada's most costly hazards. Hailstorms have been

17536-411: Is suggested that the antimatter positrons are formed in terrestrial gamma-ray flashes (TGF). TGFs are brief bursts occurring inside thunderstorms and associated with lightning. The streams of positrons and electrons collide higher in the atmosphere to generate more gamma rays. About 500 TGFs may occur every day worldwide, but mostly go undetected. In more contemporary times, thunderstorms have taken on

17810-445: Is the generic term for a warm-cored, non-frontal synoptic-scale low-pressure system over tropical or subtropical waters around the world. The systems generally have a well-defined center which is surrounded by deep atmospheric convection and a closed wind circulation at the surface. A tropical cyclone is generally deemed to have formed once mean surface winds in excess of 35 kn (65 km/h; 40 mph) are observed. It

18084-512: Is the greatest. However, each particular basin has its own seasonal patterns. On a worldwide scale, May is the least active month, while September is the most active month. November is the only month in which all the tropical cyclone basins are in season. In the Northern Atlantic Ocean , a distinct cyclone season occurs from June 1 to November 30, sharply peaking from late August through September. The statistical peak of

18358-586: Is the most common type of thunderstorm development. Mature thunderstorms are found near the center of the cluster, while dissipating thunderstorms exist on their downwind side. Multicell storms form as clusters of storms but may then evolve into one or more squall lines . While each cell of the cluster may only last 20 minutes, the cluster itself may persist for hours at a time. They often arise from convective updrafts in or near mountain ranges and linear weather boundaries, such as strong cold fronts or troughs of low pressure. These type of storms are stronger than

18632-405: Is the storm's wind speed and r {\textstyle r} is the radius of hurricane-force winds. The Hurricane Severity Index is a scale that can assign up to 50 points to a system; up to 25 points come from intensity, while the other 25 come from the size of the storm's wind field. The IKE model measures the destructive capability of a tropical cyclone via winds, waves, and surge. It

18906-437: Is usually caused by the heavy liquid precipitation that accompanies it. Flash floods are most common in arid regions as well as densely populated urban environments, where few plants, and bodies of water are present to absorb and contain the extra water. Flash flooding can be hazardous to small infrastructure, such as bridges, and weakly constructed buildings. Plants and crops in agricultural areas can be destroyed and devastated by

19180-526: The 12th parallel north and across the tropical Atlantic Ocean , reaching tropical storm strength on September 11, and hurricane strength on September 13, while located about 1,265 mi (2,035 km) east of the Leeward Islands . The presence of another area of low-pressure north of Puerto Rico produced a gap in the Azores High , causing Hugo to then gradually turn towards

19454-556: The African easterly jet and areas of atmospheric instability give rise to cyclones in the Atlantic Ocean and Caribbean Sea . Heat energy from the ocean acts as the accelerator for tropical cyclones. This causes inland regions to suffer far less damage from cyclones than coastal regions, although the impacts of flooding are felt across the board. Coastal damage may be caused by strong winds and rain, high waves (due to winds), storm surges (due to wind and severe pressure changes), and

19728-513: The Atlantic Ocean or northeastern Pacific Ocean , and a typhoon occurs in the northwestern Pacific Ocean. In the Indian Ocean and South Pacific, comparable storms are referred to as "tropical cyclones", and such storms in the Indian Ocean can also be called "severe cyclonic storms". Tropical refers to the geographical origin of these systems, which form almost exclusively over tropical seas. Cyclone refers to their winds moving in

20002-723: The Benjamín Rivera Noriega Airport was completely destroyed. Many boats in Culebra were damaged, including those that sought refuge in Ensenada Honda. On Vieques, a peak gust of 98 mph (158 km/h) was registered, though the damage suggested that gusts of up to 132 mph (212 km/h) may have impacted the island. The roof of a baseball stadium was pried off by the winds. A thousand families in Vieques were left homeless. The worst damage on

20276-582: The Dominican Republic on September 18. Buildings were boarded up in Nassau, Bahamas , and classes were cancelled at The College of The Bahamas on September 18. After Hugo departed the Caribbean, officials in South Florida convened on September 18 to discuss emergency preparedness plans, and some residents began to gather supplies. NHC director Bob Sheets stated that if Hugo were to reach

20550-666: The Doppler on Wheels , vehicles with mounted automated weather stations , weather balloons , and unmanned aircraft to investigate thunderstorms expected to produce severe weather. Lightning is detected remotely using sensors that detect cloud-to-ground lightning strokes with 95 percent accuracy in detection and within 250 metres (820 ft) of their point of origin. Thunderstorms strongly influenced many early civilizations. Greeks believed that they were battles waged by Zeus , who hurled lightning bolts forged by Hephaestus . Some American Indian tribes associated thunderstorms with

20824-490: The Earth's atmosphere . In the mature stage of a thunderstorm, the warmed air continues to rise until it reaches an area of warmer air and can rise no farther. Often this 'cap' is the tropopause . The air is instead forced to spread out, giving the storm a characteristic anvil shape. The resulting cloud is called cumulonimbus incus . The water droplets coalesce into larger and heavier droplets and freeze to become ice particles. As these fall, they melt to become rain. If

21098-438: The Earth's atmosphere . Weaker thunderstorms are steered by winds closer to the Earth's surface than stronger thunderstorms, as the weaker thunderstorms are not as tall. Organized, long-lived thunderstorm cells and complexes move at a right angle to the direction of the vertical wind shear vector. If the gust front, or leading edge of the outflow boundary, races ahead of the thunderstorm, its motion will accelerate in tandem. This

21372-775: The East Coast of the United States on September 20, escalating to a hurricane warning for some coastal areas on September 21. The coverage of these watches and warnings were incrementally revised leading up to Hugo's final landfall; at their greatest extent, hurricane watches were in effect between St. Augustine, Florida , and the Chesapeake Bay , while hurricane warnings were in effect between Fernandina Beach, Florida , and Oregon Inlet in North Carolina . All tropical cyclone watches and warnings were discontinued by 16:00 UTC on September 22. Barbados served as

21646-472: The Eastern United States , transitioning into an extratropical cyclone on September 23 before it was last noted in the far northern Atlantic on September 25. Hugo left extensive damage in its wake, causing 67 deaths and $ 11 billion (equivalent to $ 27 billion in 2023) in damage, which at the time, made it the costliest hurricane on record. Guadeloupe bore the brunt of

21920-515: The Foothills and Piedmont of North Carolina; some areas endured the resulting power outages for weeks. The National Weather Service office in Wilmington described Hugo's winds as a "unique event in weather history for this portion of inland North Carolina." Parts of Southwest Virginia were also impacted by the core of strong winds associated with Hugo, which passed through the state as

22194-573: The Grand Strand and Myrtle Beach areas experiencing only low-end hurricane-force winds, the widespread wind damage in those areas was attributed to "widespread underdesign and marginal building practices." Lesser damage occurred along the southern South Carolina coast between Charleston, South Carolina, and Savannah, Georgia , with winds there remaining below 65 mph (105 km/h). Hugo's acceleration at landfall allowed strong winds to penetrate well inland, causing widespread wind damage across

22468-476: The Gulf Stream and intensified markedly over a period of 30 hours, re-strengthening to a Category 4 hurricane. At 04:00 UTC on September 22, Hugo made its last landfall landfall on Sullivan's Island, South Carolina , with sustained winds of 140 mph (220 km/h). Hugo's forward motion was beginning to accelerate northward at the time in response to an extratropical cyclone moving across

22742-647: The Hurricane Surge Index , the Hurricane Severity Index , the Power Dissipation Index (PDI), and integrated kinetic energy (IKE). ACE is a metric of the total energy a system has exerted over its lifespan. ACE is calculated by summing the squares of a cyclone's sustained wind speed, every six hours as long as the system is at or above tropical storm intensity and either tropical or subtropical. The calculation of

23016-526: The Insurrection Act of 1807 , the Pentagon sent 1,100 troops and federal marshals to augment the security presence as local police and the National Guard lost control of the situation. Among the deployments were 470 troops from the 16th Military Police Brigade , 560 troops from the 503rd Military Police Battalion, and three helicopters and medical support. Dubbed Operation Hawkeye,

23290-574: The Leeward Islands , and collectively suffered over $ 1 billion in damage and recorded 21 fatalities. Though less severe, widespread damage was also inflicted by Hugo across the remainder of the Leeward and Windward Islands. Extensive flooding occurred on Antigua, and power outages befell the island after utility poles were uprooted by the storm. There were 2 deaths and 181 injuries. Another 509 people were left homeless following damage wrought to 15 percent of homes. Partial damage

23564-559: The Madden–Julian oscillation . The IPCC Sixth Assessment Report summarize the latest scientific findings about the impact of climate change on tropical cyclones. According to the report, we have now better understanding about the impact of climate change on tropical storm than before. Major tropical storms likely became more frequent in the last 40 years. We can say with high confidence that climate change increase rainfall during tropical cyclones. We can say with high confidence that

23838-548: The National Oceanic and Atmospheric Administration 's Storm Data publication, there were 35 deaths associated with Hugo in South Carolina. The hurricane's forces killed 13 people while another 22 fatalities were considered "indirectly-related". Among the indirect fatalities were two people killed by house fires started by candles during the storm. Another 420 people were injured throughout

24112-550: The National Severe Storms Forecast Center received unconfirmed reports of tornadoes produced by Hugo in South Carolina and west-central North Carolina, though it was difficult to differentiate tornadic damage from the broader-swaths of wind damage caused by the hurricane. There were 26 fatalities in the United States attributed directly to the weather conditions produced by Hugo; among the country's states and territories, South Carolina had

24386-663: The Niagara Falls area, winds between 37 and 43 mph (60 and 69 km/h) were reported. Winds near 47 mph (76 km/h) were also reported in Toronto. Heavy rainfall also occurred in Ontario, with precipitation in Ontario peaking at 4.5 in (110 mm), while a maximum amount of 1.85 in (47 mm) was reported in Toronto. As a result of the storm, blackouts and car accidents were reported in Toronto. Furthermore, heavy rains and high winds also occurred across

24660-471: The Pitahaya and Espíritu Santo rivers. Floods impacted areas near Luqillo and low-lying portions of San Juan after water pumps lost power. Two hundred landslides occurred in Puerto Rico, with the largest of these transporting 40,000 m (1,400,000 cu ft) of debris into a river. Culebra and Vieques, two small islands east of Puerto Rico, experienced harsher impacts than the main island; between

24934-655: The Rocky Mountains as part of the North American Monsoon regime. In the Northeast , storms take on similar characteristics and patterns as the Midwest, but with less frequency and severity. During the summer, air-mass thunderstorms are an almost daily occurrence over central and southern parts of Florida. If the quantity of water that is condensed in and subsequently precipitated from a cloud

25208-404: The Saffir–Simpson scale . Climate oscillations such as El Niño–Southern Oscillation (ENSO) and the Madden–Julian oscillation modulate the timing and frequency of tropical cyclone development. Rossby waves can aid in the formation of a new tropical cyclone by disseminating the energy of an existing, mature storm. Kelvin waves can contribute to tropical cyclone formation by regulating

25482-575: The Saffir–Simpson scale . The trend was most clear in the North Atlantic and in the Southern Indian Ocean. In the North Pacific, tropical cyclones have been moving poleward into colder waters and there was no increase in intensity over this period. With 2 °C (3.6 °F) warming, a greater percentage (+13%) of tropical cyclones are expected to reach Category 4 and 5 strength. A 2019 study indicates that climate change has been driving

25756-529: The Thunderbird , who they believed was a servant of the Great Spirit . The Norse considered thunderstorms to occur when Thor went to fight Jötnar , with the thunder and lightning being the effect of his strikes with the hammer Mjölnir . Hinduism recognizes Indra as the god of rain and thunderstorms. Christian doctrine accepts that fierce storms are the work of God. These ideas were still within

26030-550: The United States rainfall climatology over the Great Plains since they bring the region about half of their annual warm season rainfall. The two major ways thunderstorms move are via advection of the wind and propagation along outflow boundaries towards sources of greater heat and moisture. Many thunderstorms move with the mean wind speed through the Earth's troposphere , the lowest 8 kilometres (5.0 mi) of

26304-614: The Virgin Islands and Puerto Rico, causing over $ 1 billion in damage. Wind gusts up to 168 mph (270 km/h) were measured in Saint Croix, where property damage exceeded $ 500 million with over 90 percent of buildings damaged; three people were killed on the island. Widespread damage occurred in Puerto Rico and much of the island suffered power and water service failures. Eight people were killed in Puerto Rico and nearly 28,000 people were left homeless. In

26578-437: The equator , but are less common within areas of high latitude . Flash flooding is the process where a landscape, most notably an urban environment, is subjected to rapid floods. These rapid floods occur more quickly and are more localized than seasonal river flooding or areal flooding and are frequently (though not always) associated with intense rainfall. Flash flooding can frequently occur in slow-moving thunderstorms and

26852-418: The lifted index can be used to assist in determining potential upward vertical development of clouds. Generally, thunderstorms require three conditions in order to form: All thunderstorms, regardless of type, go through three stages: the developing stage , the mature stage , and the dissipation stage . The average thunderstorm has a 24 km (15 mi) diameter. Depending on the conditions present in

27126-599: The mid-latitude , where warm, moist air from tropical latitudes collides with cooler air from polar latitudes. Thunderstorms are responsible for the development and formation of many severe weather phenomena, which can be potentially hazardous. Damage that results from thunderstorms is mainly inflicted by downburst winds, large hailstones, and flash flooding caused by heavy precipitation . Stronger thunderstorm cells are capable of producing tornadoes and waterspouts . There are three types of thunderstorms: single-cell , multi-cell , and supercell . Supercell thunderstorms are

27400-514: The troposphere , enough Coriolis force to develop a low-pressure center , and a pre-existing low-level focus or disturbance. There is a limit on tropical cyclone intensity which is strongly related to the water temperatures along its path. and upper-level divergence. An average of 86 tropical cyclones of tropical storm intensity form annually worldwide. Of those, 47 reach strength higher than 119 km/h (74 mph), and 20 become intense tropical cyclones, of at least Category 3 intensity on

27674-504: The water vapor in that rising air condenses . When the moisture condenses, it releases energy known as latent heat of condensation, which allows the rising packet of air to cool less than the cooler surrounding air continuing the cloud's ascension. If enough instability is present in the atmosphere, this process will continue long enough for cumulonimbus clouds to form and produce lightning and thunder . Meteorological indices such as convective available potential energy (CAPE) and

27948-475: The 18th century. Beyond the Earth's atmosphere, thunderstorms have also been observed on the planets of Jupiter , Saturn , Neptune , and, probably, Venus . Warm air has a lower density than cool air, so warmer air rises upwards and cooler air will settle at the bottom (this effect can be seen with a hot air balloon ). Clouds form as relatively warmer air, carrying moisture, rises within cooler air. The moist air rises, and, as it does so, it cools and some of

28222-455: The 9-mile-wide (14 km) eye while bringing the plane to a gradual ascent. Fuel was also ejected from Kermit 's lower fuselage. The plane climbed to an altitude of 7,200 ft (2,200 m) before departing the eye via the northeast eyewall and returning to Grantley Adams International Airport in Barbados. In the northeastern Caribbean, warnings issued by the NHC were disseminated by

28496-640: The Atlantic hurricane season is September 10. The Northeast Pacific Ocean has a broader period of activity, but in a similar time frame to the Atlantic. The Northwest Pacific sees tropical cyclones year-round, with a minimum in February and March and a peak in early September. In the North Indian basin, storms are most common from April to December, with peaks in May and November. In the Southern Hemisphere,

28770-442: The Caribbean, causing considerable destruction. Estimates of the damage toll in this region vary but include over $ 50 million each for the British Virgin Islands and Netherlands Antilles, $ 2 billion for Puerto Rico, and $ 500 million for Saint Croix. Hugo's center was 85 mi (137 km) southwest of Sint Maarten at its closest approach; a station there reported a maximum sustained wind 46 mph (74 km/h) and

29044-467: The Carolinas was issued 30 hours before Hugo's landfall. Charleston County, South Carolina , officials began recommending evacuations on the evening of September 20; this was later changed to an evacuation order. Beaufort County, South Carolina , declared a state of emergency on September 20 and implemented voluntary evacuations. Carroll A. Campbell Jr. , the Governor of South Carolina , issued

29318-556: The Equator generally have their origins in the Intertropical Convergence Zone , where winds blow from either the northeast or southeast. Within this broad area of low-pressure, air is heated over the warm tropical ocean and rises in discrete parcels, which causes thundery showers to form. These showers dissipate quite quickly; however, they can group together into large clusters of thunderstorms. This creates

29592-497: The Kinsale and St. Patrick's areas. Impacts on upscale hotels contributed to the overall loss of 88 percent of hotel rooms on the island. Ten people were killed in Montserrat and 89 others were injured. Hugo was the first significant hurricane to strike the Virgin Islands and Puerto Rico region since Hurricane Betsy in 1956 . Hugo tracked through the Virgin Islands on September 18 and destroyed 30 percent of homes in

29866-855: The Leeward Islands at the time, this made Hugo the easternmost Category 5 hurricane on record in the Atlantic. Its winds tapered as it approached the Caribbean ; at 05:00 UTC on September 17, Hugo's eye passed over Guadeloupe with sustained winds of 140 mph (220 km/h). The next day, the hurricane made three landfalls, first on Saint Croix in the U.S. Virgin Islands , with sustained winds of 140 mph (220 km/h), followed by Vieques and Fajardo in Puerto Rico , with sustained winds of 125 mph (205 km/h) in each instance. Hugo's encounter with Puerto Rico weakened

30140-632: The PDI is similar in nature to ACE, with the major difference being that wind speeds are cubed rather than squared. The Hurricane Surge Index is a metric of the potential damage a storm may inflict via storm surge. It is calculated by squaring the dividend of the storm's wind speed and a climatological value (33 m/s or 74 mph), and then multiplying that quantity by the dividend of the radius of hurricane-force winds and its climatological value (96.6 km or 60.0 mi). This can be represented in equation form as: where v {\textstyle v}

30414-418: The Puerto Rico territory on September 18—on Vieques and Fajardo—as a high-end Category 3 hurricane with maximum sustained winds estimated at 125 mph (201 km/h). An anemometer on the ship Night Cap registered a wind gust of 170 mph (270 km/h) while harbored at Culebra . The strongest wind recorded on Puerto Rico's main island was documented at Roosevelt Roads Naval Station , which reported

30688-463: The South Atlantic is not a major basin, and not an official basin according to the WMO. Each year on average, around 80 to 90 named tropical cyclones form around the world, of which over half develop hurricane-force winds of 65 kn (120 km/h; 75 mph) or more. Worldwide, tropical cyclone activity peaks in late summer, when the difference between temperatures aloft and sea surface temperatures

30962-449: The South Carolina coast, Hugo produced storm tides as high as 20 ft (6.1 m). The maximum recorded storm surge was 20.2 ft (6.2 m) along Seewee Bay south of McClellanville . This rise in water induced by Hugo resulted in the highest storm tides ever recorded along the U.S. East Coast . Between 3–8 in (76–203 mm) of rain fell across a swath 150 mi (240 km) wide over South Carolina. The maximum rainfall in

31236-483: The South Carolina mainland to Sullivan's Island was heavily damaged and became stuck in an open position. Rows of beachfront homes on Sullivan's Island were razed by the surge. Ships at the marina in Isle of Palms were crumpled into a heap on the mainland shore. Beach homes on Isle of Palms were moved 150 ft (46 m) off their foundations by an 11-foot (3.4 m) storm surge; in total, 60 homes were destroyed on

31510-928: The U.S. Office of Foreign Disaster Assistance (OFDA). Additional relief teams from the OFDA, Pan American Health Organization , Red Cross , and United Nations Office of the United Nations Disaster Relief Coordinator were pre-positioned in Antigua to survey the damage and prioritize aid in Hugo's aftermath. The government of Dominica urged its citizens to take emergency precautions. The Dominican Ministry of Public Works prepositioned earthmoving equipment around Dominica to clear landslide debris. A curfew in Guadeloupe mandating that streets be clear of pedestrians and vehicles came into effect at 6 p.m. AST on September 17. Leading up to

31784-568: The U.S. Coast Guard found that winds unroofed 80 percent of homes between San Juan and Fajardo. Roosevelt Roads Naval Station took heavy damage and lost power and water service. Practically every building was damaged, though only minor injuries occurred. High waves along the coast of the San Juan metropolitan area destroyed walls and sidewalks. Condado suffered widespread damage and debris bestrewed its streets. A mobile home park in Loíza , one of

32058-465: The U.S. Virgin Islands a disaster area. A temporary air traffic control tower was erected at Alexander Hamilton Airport in Saint Croix six days after the storm. Cyril E. King Airport in Saint Thomas, having suffered less damage, resumed operations within 24 hours. Power was restored in most of Saint Croix and Saint Thomas within three months. The islands' telephone systems were badly crippled by

32332-542: The U.S. Virgin Islands. The eye of Hugo moved ashore South Carolina at Sullivan's Island at 04:00 UTC on September 22 (12:00 a.m. EDT ). The storm's maximum sustained winds were estimated by the NHC to have reached 140 mph (230 km/h) during landfall, making Hugo a Category 4 hurricane. This estimate was derived from an aircraft reconnaissance flight into the storm shortly before landfall; no weather stations were positioned along Bulls Bay, where Hugo's strongest winds likely occurred. This intensity made Hugo

32606-419: The U.S. Virgin Islands. Although the most heavily impacted areas had relatively low population, Hugo moved over heavily forested areas; this was unusual for a hurricane striking the United States, and led to significant secondary damage from falling trees. Hugo was also the most powerful storm to strike the country since Hurricane Camille in 1969 . In addition to the rain, surge, and wind associated with Hugo,

32880-552: The U.S. incurred $ 8.671 billion in damage from Hugo, with $ 7.071 billion in the contiguous U.S. and $ 1.6 billion in Puerto Rico and the U.S. Virgin Islands . The San Juan Star , a Puerto Rican newspaper, calculated that losses in Puerto Rico amounted to $ 2 billion. Insured property damage in the contiguous U.S. reached $ 3.042 billion according to the American Insurance Association , with another $ 1.881 billion in Puerto Rico and

33154-610: The United States National Hurricane Center and Fiji Meteorological Service issue alerts, watches and warnings for various island nations in their areas of responsibility. The United States Joint Typhoon Warning Center and Fleet Weather Center also publicly issue warnings about tropical cyclones on behalf of the United States Government . The Brazilian Navy Hydrographic Center names South Atlantic tropical cyclones , however

33428-584: The United States, it could move ashore "anywhere from the Florida Keys to North Carolina." NASA delayed the September 22 launch of an Atlas-Centaur rocket with Hugo looming. Boats were moved from coastal marinas to more protected harbors inland near St. Simons, Georgia . The American Red Cross readied 58 shelters in Miami, Florida , and 23 shelters in Fort Lauderdale, Florida . Equipment

33702-591: The Western Pacific. Tropical cyclones have to have a significant amount of gale-force winds occurring around the center before they are named within the Southern Hemisphere . The names of significant tropical cyclones in the North Atlantic Ocean, Pacific Ocean, and Australian region are retired from the naming lists and replaced with another name. Tropical cyclones that develop around the world are assigned an identification code consisting of

33976-460: The administrator for Horry County, said that the city "for all practical purposes is gone." Severe beach erosion also occurred in Myrtle Beach and North Myrtle Beach . Piers along the coast of Horry County were heavily damaged by storm surge. The pier at Sunset Beach was reduced to its pilings. Myrtle Beach Air Force Base sustained $ 2 million in damage from buildings and equipment. With

34250-459: The airport terminated operations. Cruise ships with San Juan as their port of call were rerouted elsewhere. One person was killed in Utuado, Puerto Rico , after being electrocuted by a power line while preparing for the storm. On September 18, Puerto Rican Governor Rafael Hernández Colón ordered a shutdown of the island's electric grid to mitigate damage. A state of emergency was declared in

34524-668: The annual timber harvest; this was a greater loss of timber than observed in Hurricane Camille, the 1980 eruption of Mount St. Helens , and the Yellowstone fires of 1988 , combined. Berkeley , Clarendon , Florence , Lee , Sumter , and Williamsburg counties each experienced damage to more than 90 percent of timberland. A conservative estimate valued the lost timber statewide at $ 1.04 billion. Downed trees and wind-blown debris severed power lines, cutting power for most areas. Three power plants were also disabled by

34798-432: The archipelago. Generally 6–9 in (150–230 mm) of rain fell across the Virgin Islands, peaking at 11.2 in (280 mm) at Hams Bluff Light in northwestern Saint Croix. However, most rain gauges in the Virgin Islands were destroyed by the hurricane. The eye of Hugo passed over Saint Croix at 06:00 UTC on September 18 (02:00 a.m. AST). Hurricane-force winds lasted for an unusually long time, battering

35072-589: The atmosphere, each of these three stages take an average of 30 minutes. The first stage of a thunderstorm is the cumulus stage or developing stage. During this stage, masses of moisture are lifted upwards into the atmosphere. The trigger for this lift can be solar illumination , where the heating of the ground produces thermals , or where two winds converge forcing air upwards, or where winds blow over terrain of increasing elevation. The moisture carried upward cools into liquid drops of water due to lower temperatures at high altitude, which appear as cumulus clouds. As

35346-764: The back edge of the rain shield associated with mature squall lines, a wake low can form, which is a mesoscale low pressure area that forms behind the mesoscale high pressure system normally present under the rain canopy, which are sometimes associated with a heat burst . This kind of storm is also known as "Wind of the Stony Lake" ( simplified Chinese : 石湖风 ; traditional Chinese : 石湖風 ; shi2 hu2 feng1) in southern China. Supercell storms are large, usually severe , quasi-steady-state storms that form in an environment where wind speed or wind direction varies with height (" wind shear "), and they have separate downdrafts and updrafts (i.e., where its associated precipitation

35620-402: The bulk of the occurrences from May through September. Cheyenne, Wyoming , is North America's most hail-prone city with an average of nine to ten hailstorms per season. In South America, areas prone to hail are cities like Bogotá, Colombia. Hail can cause serious damage, notably to automobiles , aircraft, skylights, glass-roofed structures, livestock, and most commonly, farmers' crops . Hail

35894-510: The cause of costly and deadly events throughout history. One of the earliest recorded incidents occurred around the 9th century in Roopkund , Uttarakhand, India. The largest hailstone in terms of maximum circumference and length ever recorded in the United States fell in 2003 in Aurora, Nebraska , United States. A tornado is a violent, rotating column of air in contact with both the surface of

36168-559: The central U.S., and this curvature and acceleration continued as Hugo moved farther inland. The intensity of the winds decreased after landfall, particularly as Hugo began interacting with the Appalachian Mountains ; by dawn on September 22, Hugo was downgraded to a tropical storm when it was just west of Charlotte, North Carolina . The next day, it transitioned into an extratropical storm near Erie, Pennsylvania , and continued across eastern Canada , eventually moving into

36442-477: The city pier, tearing away parts of its concrete decking. Saint Thomas experienced hurricane-force winds and sustained widespread damage to property and vegetation; damage was less severe than on Saint Croix due to Saint Thomas's position farther away from the core of Hugo. A field survey conducted by the National Academy of Sciences estimated that gusts of up to 121 mph (195 km/h) occurred on

36716-453: The coast. A total of 264,000 people were evacuated in South Carolina; most took shelter in the homes of friends or relatives, and relatively few sought refuge in public shelters. A fifth of evacuees took refuge within 30 minutes of their homes. An estimated 96 percent of people on the high-risk barrier islands and beaches evacuated, while 75–80 percent of people in moderate-risk areas evacuated. Most did not evacuate until after

36990-455: The collapse of their homes. The U.S. Route 17 bridge across Awendaw Creek in Awendaw was destroyed by a 19.4 ft (5.9 m) storm tide. Extensive losses to timber occurred at Francis Marion National Forest , where 75 percent of marketable trees were felled. Most trees were truncated 10–25 ft (3.0–7.6 m) above the ground, with others snapped or uprooted; the cost of damage

37264-467: The country's gross domestic product . Homes, government buildings, and trees were damaged by the storm. A fifth of the country was rendered homeless and the entire populace lost power and water. Ninety percent of the residents of Nevis lost their homes. One person was killed after a wall collapsed upon him. Dominica was most affected among the Windward Islands. Hugo ruined 80 percent of

37538-560: The curfew, residents rushed hardware stores and supermarkets to stock up on supplies. Many on the Atlantic-facing side of Guadeloupe evacuated farther inland. Cable television played a significant role in keeping residents of Martinique updated on the hurricane's approach. Though no formal evacuation order was enacted for Martinique, the prefect of Martinique recommended the evacuation of the low-lying Kinsale area on September 16. Twenty-four evacuation shelters were opened throughout

37812-492: The damage toll was $ 1 billion. Losses to crops and livestock amounted to nearly $ 97 million. There were seven fatalities in the state. Storm surge along the coast of North Carolina west of Cape Fear reached 9 ft (2.7 m) above mean sea level. Three beach communities in Brunswick County, North Carolina , incurred a total of $ 55 million in damage; with at least 25 beachfront homes battered by

38086-639: The damage wrought. Stores were damaged in Christiansted. Power and water distillation facilities operated by the Virgin Islands Water & Power Authority west of the city were disabled by the storm. The rupture of a fuel oil tank on the facility grounds caused an oil spill in the Christiansted harbor. Severe damage occurred in south-central Saint Croix near the Hovensa oil refinery and Alexander Hamilton International Airport . Oil tanks at

38360-431: The danger of lightning . Thunderstorm preparedness and safety refers to taking steps before, during, and after a thunderstorm to minimize injury and damage. Preparedness refers to precautions that should be taken before a thunderstorm. Some preparedness takes the form of general readiness (as a thunderstorm can occur at any time of the day or year). Preparing a family emergency plan, for example, can save valuable time if

38634-466: The destruction of 150 homes. Major damage was inflicted upon 350 homes and minor damage was inflicted upon another 500 homes, with their aggregate losses amounting to $ 87 million. Farms and businesses around Georgetown sustained $ 10 million in damage. Only a few beachfront homes withstood the hurricane in Pawleys Island . Debris from destroyed homes piled atop streets along

38908-497: The development of organized convection. This term technically applies to a single thunderstorm with one main updraft. Also known as air-mass thunderstorms , these are the typical summer thunderstorms in many temperate locales. They also occur in the cool unstable air that often follows the passage of a cold front from the sea during winter. Within a cluster of thunderstorms, the term "cell" refers to each separate principal updraft. Thunderstorm cells occasionally form in isolation, as

39182-435: The development of the westerlies . Cyclone formation is usually reduced 3 days prior to the wave's crest and increased during the 3 days after. The majority of tropical cyclones each year form in one of seven tropical cyclone basins, which are monitored by a variety of meteorological services and warning centers. Ten of these warning centers worldwide are designated as either a Regional Specialized Meteorological Centre or

39456-637: The earth and a cumulonimbus cloud (otherwise known as a thundercloud) or, in rare cases, the base of a cumulus cloud . Tornadoes come in many sizes but are typically in the form of a visible condensation funnel , whose narrow end touches the earth and is often encircled by a cloud of debris and dust . Most tornadoes have wind speeds between 40 and 110 mph (64 and 177 km/h), are approximately 75 metres (246 ft) across, and travel several kilometers (a few miles) before dissipating. Some attain wind speeds of more than 300 mph (480 km/h), stretch more than 1,600 metres (1 mi) across, and stay on

39730-675: The eastern Great Lakes region and a strong high-pressure system off the U.S. East Coast generated a sharp contrast in pressure . This led to strong winds over the Mid-Atlantic states and New England . Nearly 85,000 homes and businesses lost power on Long Island . One person was killed in Norwich, New York , after a falling tree struck the car he was in. Fifteen counties in Pennsylvania reported high winds in connection with Hugo, with some sustaining damage to trees. Connecticut

40004-439: The eastern two-thirds of the state. The NOAA classified wind damage as "extensive" in 15 counties. Devastated groves of pine trees were characteristic of the hurricane's impacts, in addition to numerous unroofed homes and cotton crops injured by the winds and rain. Over one-third of all timber in the state was damaged, with the damage most extensive near the coast and locations that were northeast of Hugo's eye as it moved across

40278-515: The entirety of its banana crop and most of its coconut palms and sugar cane crop. Habitat loss caused bat populations in Montserrat to fall 20-fold, while the populations of several endemic bird species declined or were disrupted across the eastern Caribbean. Coastal bird populations in South Carolina were forced 200 mi (320 km) inland. Additionally, forests between South Carolina and Virginia were heavily damaged; in South Carolina alone

40552-492: The equator, then move poleward past the ridge axis before recurving into the main belt of the Westerlies . When the subtropical ridge position shifts due to El Niño, so will the preferred tropical cyclone tracks. Areas west of Japan and Korea tend to experience much fewer September–November tropical cyclone impacts during El Niño and neutral years. During La Niña years, the formation of tropical cyclones, along with

40826-800: The evacuation of the Oakdale area in Harrison County, West Virginia . Widespread flash flooding occurred across eastern Tennessee , forcing the evacuation of people from affected areas; some of the evacuees had fled South Carolina for the Great Smoky Mountains . Three hundred people were driven out of Carter County . Floods there swamped homes and the downtown area of Roan Mountain . Bridges and roads were washed out in Greene and Johnson counties. Numerous creeks overflowed their banks in northeastern Ohio following heavy rainfall from

41100-626: The extent of the damage suggested that the entire island was within the envelope of the hurricane's strongest winds. Anemometers on two U.S. Navy workboats recorded peak gusts of 161 and 168 mph (259 and 270 km/h). Unofficial reports alleged that Saint Croix experienced gusts in excess of 200 mph (320 km/h), but these were inconsistent with the severity of damage or were otherwise unsubstantiated. Hugo killed 3 people and left 3,500 homeless on Saint Croix. Private and government property damage exceeded $ 500 million. Electricity, power, and water services were cut by Hugo across

41374-481: The eyewall of the storm, and an upper-level anticyclone helps channel this air away from the cyclone efficiently. However, some cyclones such as Hurricane Epsilon have rapidly intensified despite relatively unfavorable conditions. There are a number of ways a tropical cyclone can weaken, dissipate, or lose its tropical characteristics. These include making landfall, moving over cooler water, encountering dry air, or interacting with other weather systems; however, once

41648-515: The far northern Atlantic where it was last noted on September 25. Between September 15 and September 22, aircraft from the U.S. Air Force (USAF) and National Oceanic and Atmospheric Administration (NOAA) penetrated the eye of Hugo 76 times, documenting the location of the storm's center roughly once every two hours. Among these planes was a WP-3D Orion serviced by the NOAA and nicknamed Kermit ( callsign N42RF ). It had been deployed to Barbados alongside another WP-3D Orion as part of

41922-528: The few in Puerto Rico, was wiped out by the storm surge and strong winds. The winds overturned cars and toppled trees and streetlights around the city. Buildings in downtown San Juan suffered partial wall and window failures, though overall damage to buildings in the city was light. Fifty airplanes were destroyed at Luis Muñoz Marín International Airport; repairs to the airport would cost $ 20 million. Power outages affected 80 percent of Puerto Rico. Power and water supplies in San Juan were cut for more than

42196-431: The first floors of homes in downtown Charleston. Eighty percent of roofs in the city were damaged, with many already susceptible to strong winds due to poor maintenance and weak structural integrity. At least 3,200 historic structures in Charleston were damaged and 95 percent of urban trees were lost. Naval Weapons Station Charleston sustained $ 95–$ 100 million in damage. Two people were killed in Charleston by

42470-429: The force exerted by downburst winds. Downburst winds are usually formed in areas when high pressure air systems of downdrafts begin to sink and displace the air masses below it, due to their higher density. When these downdrafts reach the surface, they spread out and turn into the destructive straight-horizontal winds. Thunderstorm asthma is the triggering of an asthma attack by environmental conditions directly caused by

42744-739: The force of raging water. Automobiles parked within affected areas can also be displaced. Soil erosion can occur as well, exposing risks of landslide phenomena. Downburst winds can produce numerous hazards to landscapes experiencing thunderstorms. Downburst winds are generally very powerful, and are often mistaken for wind speeds produced by tornadoes, due to the concentrated amount of force exerted by their straight-horizontal characteristic. Downburst winds can be hazardous to unstable, incomplete, or weakly constructed infrastructures and buildings. Agricultural crops, and other plants in nearby environments can be uprooted and damaged. Aircraft engaged in takeoff or landing can crash. Automobiles can be displaced by

43018-433: The forest blocked Puerto Rico Highway 191 and strong winds unroofed the local headquarters of the United States Forest Service . Fallen power lines and damage to over 120 homes marooned the mayor of Arroyo and several others; the municipality had been struck by waves 35 ft (11 m) high. Damage to highways in Puerto Rico amounted to $ 40 million, though only one bridge required closure for repairs. Crops on

43292-410: The form of cold water from falling raindrops (this is because the atmosphere is cooler at higher altitudes). Cloud cover may also play a role in cooling the ocean, by shielding the ocean surface from direct sunlight before and slightly after the storm passage. All these effects can combine to produce a dramatic drop in sea surface temperature over a large area in just a few days. Conversely, the mixing of

43566-427: The form of strong straight-line winds can be expected in areas where the squall line itself is in the shape of a bow echo , within the portion of the line that bows out the most. Tornadoes can be found along waves within a line echo wave pattern , or LEWP, where mesoscale low pressure areas are present. Some bow echoes in the summer are called derechos , and move quite fast through large sections of territory. On

43840-453: The frequency of very intense storms and a poleward extension of where the cyclones reach maximum intensity are among the possible consequences of human-induced climate change. Tropical cyclones use warm, moist air as their fuel. As climate change is warming ocean temperatures , there is potentially more of this fuel available. Between 1979 and 2017, there was a global increase in the proportion of tropical cyclones of Category 3 and higher on

44114-532: The general public regarding forecasts, watches, and warnings. Since the systems can last a week or longer, and more than one can be occurring in the same basin at the same time, the names are thought to reduce the confusion about what storm is being described. Names are assigned in order from predetermined lists with one, three, or ten-minute sustained wind speeds of more than 65 km/h (40 mph) depending on which basin it originates. Standards vary from basin to basin. Some tropical depressions are named in

44388-477: The greatest frequency in tropical rainforest areas, where they may occur nearly daily. At any given time, approximately 2,000 thunderstorms are occurring on Earth. Kampala and Tororo in Uganda have each been mentioned as the most thunderous places on Earth, a claim also made for Singapore and Bogor on the Indonesian island of Java . Other cities known for frequent storm activity include Darwin , Caracas, Manila and Mumbai . Thunderstorms are associated with

44662-406: The ground for more than 100 kilometres (dozens of miles). The Fujita scale and the Enhanced Fujita Scale rate tornadoes by damage caused. An EF0 tornado, the weakest category, damages trees but does not cause significant damage to structures. An EF5 tornado, the strongest category, rips buildings off their foundations and can deform large skyscrapers. The similar TORRO scale ranges from

44936-449: The ground is known as a hailstorm. Thunderclouds that are capable of producing hailstones are often seen obtaining green coloration. Hail is more common along mountain ranges because mountains force horizontal winds upwards (known as orographic lifting ), thereby intensifying the updrafts within thunderstorms and making hail more likely. One of the more common regions for large hail is across mountainous northern India, which reported one of

45210-409: The highest death toll with 13 direct fatalities. The American Red Cross enumerated 70 fatalities in the Carolinas, Puerto Rico, and the U.S. Virgin Islands both directly and indirectly caused by Hugo. The homes of more than 200,000 families nationwide were damaged or destroyed; 129,687 families were affected in the Carolinas and 87,700 families were affected in Puerto Rico and

45484-410: The highest hail-related death tolls on record in 1888. China also experiences significant hailstorms. Across Europe, Croatia experiences frequent occurrences of hail. In North America, hail is most common in the area where Colorado , Nebraska , and Wyoming meet, known as "Hail Alley". Hail in this region occurs between the months of March and October during the afternoon and evening hours, with

45758-423: The hurricane and an upper-level low emerged over Georgia . These two features generated a strong southeasterly steering flow within which Hugo was contained, shaping its trajectory towards the Southeastern United States . As the hurricane accelerated away from Puerto Rico at about 14 mph (22 km/h), it became better organized and its eye became increasingly well defined. On September 21, Hugo passed over

46032-413: The hurricane warning and mandatory evacuation order were issued. Accurate forecasts from the NHC and the resulting narrow scope of evacuations allowed the evacuations to "[proceed] as smoothly as could be expected", and contraflow traffic patterns were not required for those departing Charleston via Interstate 26 . Parts of the Georgia and North Carolina coasts also evacuated ahead of Hugo. Georgia enacted

46306-402: The instability and relative wind conditions at different layers of the atmosphere (" wind shear "). Single-cell thunderstorms form in environments of low vertical wind shear and last only 20–30 minutes. Organized thunderstorms and thunderstorm clusters/lines can have longer life cycles as they form in environments of significant vertical wind shear, normally greater than 25 knots (13 m/s) in

46580-451: The intensity from leveling off before an eye emerges in infrared imagery. The SATCON weights estimates from various satellite-based systems and microwave sounders , accounting for the strengths and flaws in each individual estimate, to produce a consensus estimate of a tropical cyclone's intensity which can be more reliable than the Dvorak technique at times. Multiple intensity metrics are used, including accumulated cyclone energy (ACE),

46854-522: The intensity of a tropical cyclone. Reconnaissance aircraft fly around and through tropical cyclones, outfitted with specialized instruments, to collect information that can be used to ascertain the winds and pressure of a system. Tropical cyclones possess winds of different speeds at different heights. Winds recorded at flight level can be converted to find the wind speeds at the surface. Surface observations, such as ship reports, land stations, mesonets , coastal stations, and buoys, can provide information on

47128-487: The island from the late evening of September 17 to the morning of September 18. Peak sustained winds in Hugo at the time were estimated at 140 mph (230 km/h), making it a Category 4 hurricane. The winds unroofed homes and knocked out power in Saint Croix and Saint Thomas . No official wind measurements were taken on Saint Croix as weather observers evacuated their post at Alexander Hamilton International Airport (now known as Henry E. Rholsen International Airport);

47402-410: The island including banana and coffee sustained widespread losses. Hugo was the costliest hurricane in U.S. history at the time and one of its costliest disasters overall, with a damage toll of $ 8 billion estimated by the NHC. This total was over three times higher than that inflicted by Hurricane Frederic , the previous costliest hurricane. The State , a South Carolina newspaper, estimated that

47676-430: The island's banana crop and interrupted water supplies. Coastal roads were damaged by the hurricane's choppy seas; a washout along a primary thoroughfare isolated the village of Dubique. Bridges and storm drains also took heavy damage. Landslides isolated towns for many days. The damage toll in Dominica totaled $ 20 million. The hurricane moved near the Virgin Islands and made two landfalls in Puerto Rico as it egressed

47950-466: The island's electric grid was turned off. At least 30,000 people evacuated in Puerto Rico, making it one of the largest evacuations in the territory's history; government and media representatives described the evacuation as "the best coordinated weather event they could recall." Three thousand people evacuated from southeastern Puerto Rico and five thousand evacuated from San Juan neighborhoods. However, many were initially reluctant to leave. La Perla

48224-422: The island's fishing fleet, and many ships were grounded by 24-foot (7.3 m) waves. Debris blocked 70 percent of roads. There were 11 fatalities attributed to Hugo in Guadeloupe. Another 107 people were injured and 35,000 were rendered homeless. The damage toll in Guadeloupe amounted to $ 880 million. Although Montserrat was struck by many significant storms in the 18th and 19th centuries,

48498-629: The island's hotel industry suffered FF152 million in losses. The emergency operations center in Montserrat was formally activated on September 18 to effectively deal with the aftermath of Hugo. As more robust communication systems were destroyed by the storm, communications between the island and the outside world were primarily handled by amateur radio . Urgent requests for aid were forwarded by ham radio operators to all embassies and foreign missions in Barbados. The island's reduced radio capabilities were augmented by HMS  Alacrity when she arrived in Plymouth on September 18. The ship also brought

48772-465: The island's south end. Hugo caused about $ 944 million in damage in Horry County . As protective sand dunes were whittled down by the hurricane, beaches along 150 mi (240 km) of the coastal Carolinas recessed 50–200 ft (15–61 m) inland. Beaches were eroded by a 13-foot (4.0 m) surge up to the most outward row of homes in Garden City . These coastal homes were razed or washed inland, dealing damage to additional homes. M. L. Love,

49046-506: The island. Disaster preparedness plans were set into motion by Martinique's government ministries, dispatching crews to board windows and secure buildings. Air France cancelled its three Martinique -bound flights from Paris scheduled for September 18; flights to the Lesser Antilles were largely cancelled by the afternoon of September 16. Most buildings in Antigua were shuttered by noon on September 17 and all local ships were brought to their moorings. V. C. Bird International Airport closed and

49320-491: The island. Homes were unroofed and boats were heavily damaged or set adrift. The antenna, tower, and transmitter of television station WBNB-TV in Charlotte Amalie were destroyed; the station would not return to the air because of the damage and the owner's inability to afford repairs. Two people drowned in Puerto Rico during Hugo's passage according to reports from the National Research Council and NHC. Another six were killed in Guayama . The San Juan Star estimated losses in

49594-413: The island. More than 90 percent of buildings were damaged and vegetation was stripped bare throughout the island. Seventy percent of buildings were destroyed and as many as 75 percent of homes lost their roofs. Many neighborhoods were completely reduced to rubble. Surveys equated the severity of damage to that caused by an F1 or F2 tornado on the Fujita scale . In some areas, microbursts and

49868-413: The island. On the island of Saint Croix, looting and lawlessness reigned in the aftermath of Hugo. FBI agents, U.S. marshals, and local police initially maintained a patrol of Frederiksted and Christiansted while the U.S. Coast Guard evacuated tourists from the island; the USCGC Bear evacuated 40 people and sent personnel onshore to monitor the situation. However, local law enforcement in Saint Croix

50142-425: The island. The damage in Sullivan's Island and Isle of Palms combined was estimated to be approximately $ 270 million. Every building on the two islands took damage from the hurricane. Storm surge tore off the pavement from coastal roads and destroyed 80 percent at Folly Beach . All coastal state parks with the exception of Hunting Island and Edisto Beach sustained significant damage. Charleston County

50416-409: The largest island in the BVI. A third of the island's private homes were wrecked. The hurricane also caused widespread power outages in the Dominican Republic while tracking northwest towards the continental United States. Guadeloupe sustained the heaviest impacts among the Leeward Islands from Hugo. The hurricane made landfall on the island at 05:00 UTC on September 17 (01:00 a.m. AST ) as

50690-520: The last major hurricane to strike the island before Hugo occurred in 1928 . The right-front quadrant of Hugo's eyewall moved over Montserrat on September 17, raking the island with sustained winds of 140 mph (230 km/h). The island may have also experienced wind gusts up to 240 mph (390 km/h). The hurricane exacted a heavy toll over the course of 14 hours. Hugo was the costliest hurricane in Montserrat's history, inflicting $ 260 million in damage. Entire villages were destroyed by

50964-582: The late 1800s and early 1900s and gradually superseded the existing system—simply naming cyclones based on what they hit. The system currently used provides positive identification of severe weather systems in a brief form, that is readily understood and recognized by the public. The credit for the first usage of personal names for weather systems is generally given to the Queensland Government Meteorologist Clement Wragge who named systems between 1887 and 1907. This system of naming weather systems fell into disuse for several years after Wragge retired, until it

51238-532: The life of the thunderstorm. The downdraft will push down out of the thunderstorm, hit the ground and spread out. This phenomenon is known as a downburst . The cool air carried to the ground by the downdraft cuts off the inflow of the thunderstorm, the updraft disappears and the thunderstorm will dissipate. Thunderstorms in an atmosphere with virtually no vertical wind shear weaken as soon as they send out an outflow boundary in all directions, which then quickly cuts off its inflow of relatively warm, moist air, and kills

51512-422: The local topography may have amplified the winds, producing more extreme damage. The heaviest damage on Saint Croix was inflicted upon its northern coast from the mouth of the Salt River to the island's eastern end. These coastal extents were directly exposed to intense rainbands associated with Hugo. The sloping terrain near Christiansted accelerated winds near the surface by as much as 20 percent, enhancing

51786-400: The loss of timber was estimated at $ 1.04 billion. Hugo was the strongest hurricane to strike the northeastern Caribbean since Hurricane David in 1979, and the strongest to make landfall on the continental U.S. since Hurricane Camille in 1969. The scale of the hurricane's impacts led to the retirement of the name Hugo from the Atlantic tropical cyclone name list. Hurricane Hugo

52060-609: The lowest 6 kilometres (3.7 mi) of the troposphere , which aids the development of stronger updrafts as well as various forms of severe weather. The supercell is the strongest of the thunderstorms, most commonly associated with large hail, high winds, and tornado formation. Precipitable water values of greater than 31.8 millimetres (1.25 in) favor the development of organized thunderstorm complexes. Those with heavy rainfall normally have precipitable water values greater than 36.9 millimetres (1.45 in). Upstream values of CAPE of greater than 800 J/kg are usually required for

52334-404: The main belt of the Westerlies , by means of merging with a nearby frontal zone, can cause tropical cyclones to evolve into extratropical cyclones . This transition can take 1–3 days. Should a tropical cyclone make landfall or pass over an island, its circulation could start to break down, especially if it encounters mountainous terrain. When a system makes landfall on a large landmass, it

52608-494: The mainland United States, coastal South Carolina was hit by record setting storm surge heights, reaching 20.2 ft (6.2 m) near McClellanville . The surge and strong winds wrought extensive damage to buildings and infrastructure across South Carolina, and caused 13 deaths. Flood and wind impacts followed Hugo across much of the Eastern United States into Eastern Canada . There were widespread and significant agricultural impacts from Hugo. Guadeloupe sustained damage to

52882-400: The mainstream as late as the 18th century. Martin Luther was out walking when a thunderstorm began, causing him to pray to God for being saved and promising to become a monk. Thunderstorms, evidenced by flashes of lightning , on Jupiter have been detected and are associated with clouds where water may exist as both a liquid and ice, suggesting a mechanism similar to that on Earth. (Water

53156-401: The most persistent severe thunderstorms, known as supercells , rotate as do cyclones. While most thunderstorms move with the mean wind flow through the layer of the troposphere that they occupy, vertical wind shear sometimes causes a deviation in their course at a right angle to the wind shear direction. Thunderstorms result from the rapid upward movement of warm, moist air, sometimes along

53430-450: The most powerful thunderstorms over the United States occur in the Midwest and the Southern states . These storms can produce large hail and powerful tornadoes. Thunderstorms are relatively uncommon along much of the West Coast of the United States , but they occur with greater frequency in the inland areas, particularly the Sacramento and San Joaquin Valleys of California. In spring and summer, they occur nearly daily in certain areas of

53704-458: The next day. They tend to form when the surface temperature varies by more than 5 °C (9 °F) between day and night. The type that forms during the warm season over land has been noted across North America, Europe, and Asia, with a maximum in activity noted during the late afternoon and evening hours. Forms of MCS that develop in the tropics are found in use either the Intertropical Convergence Zone or monsoon troughs , generally within

53978-408: The northern coast of Puerto Rico. Rainfall on the Caribbean islands averaged between 5–10 in (130–250 mm). The NHC's preliminary report on the hurricane enumerated 28 fatalities in the eastern Caribbean while media reports tallied over 30. As many as 100,000 people may have been left homeless throughout the region as a result of Hugo. Guadeloupe and Montserrat were hardest-hit among

54252-462: The observed trend of rapid intensification of tropical cyclones in the Atlantic basin. Rapidly intensifying cyclones are hard to forecast and therefore pose additional risk to coastal communities. Warmer air can hold more water vapor: the theoretical maximum water vapor content is given by the Clausius–Clapeyron relation , which yields ≈7% increase in water vapor in the atmosphere per 1 °C (1.8 °F) warming. All models that were assessed in

54526-526: The occurrence of one thunderstorm can develop an outflow boundary that sets up new thunderstorm development. Such storms are rarely severe and are a result of local atmospheric instability; hence the term "air mass thunderstorm". When such storms have a brief period of severe weather associated with them, it is known as a pulse severe storm. Pulse severe storms are poorly organized and occur randomly in time and space, making them difficult to forecast. Single-cell thunderstorms normally last 20–30 minutes. This

54800-406: The operation involved elements of the Army, Navy and the Coast Guard, along with a contingent from the U.S. Marshals Service and the FBI, forming Joint Task Force (JTF) 40 for Operation Hawkeye. It also resulted in the first operational deployment of the National Disaster Medical System (NDMS), when the New Mexico-1 Disaster Medical Assistance Team (DMAT) was deployed to assist in medical care needs of

55074-466: The overall frequency of tropical cyclones worldwide, with increased frequency in the North Atlantic and central Pacific, and significant decreases in the southern Indian Ocean and western North Pacific. There has been a poleward expansion of the latitude at which the maximum intensity of tropical cyclones occurs, which may be associated with climate change. In the North Pacific, there may also have been an eastward expansion. Between 1949 and 2016, there

55348-498: The phenomena of thunderstorms and have numerous hazards towards landscapes and populations. One of the more significant hazards lightning can pose is the wildfires they are capable of igniting. Under a regime of low precipitation (LP) thunderstorms, where little precipitation is present, rainfall cannot prevent fires from starting when vegetation is dry as lightning produces a concentrated amount of extreme heat. Direct damage caused by lightning strikes occurs on occasion. In areas with

55622-440: The potential of spawning tornadoes . Climate change affects tropical cyclones in several ways. Scientists found that climate change can exacerbate the impact of tropical cyclones by increasing their duration, occurrence, and intensity due to the warming of ocean waters and intensification of the water cycle . Tropical cyclones draw in air from a large area and concentrate the water content of that air into precipitation over

55896-413: The presence of moderate or strong wind shear depending on the evolution and structure of the storm's convection. The size of tropical cyclones plays a role in how quickly they intensify. Smaller tropical cyclones are more prone to rapid intensification than larger ones. The Fujiwhara effect , which involves interaction between two tropical cyclones, can weaken and ultimately result in the dissipation of

56170-501: The principal island of Puerto Rico occurred along its northeast coast at Fajardo and Luquillo , where the angle of attack of Hugo's winds was most favorable for high storm surge. At Luquillo, the storm surge reached 8 ft (2.4 m), with waves atop the elevated waters reaching at least 10 ft (3.0 m). Two ferries were grounded at Fajardo by the storm surge; boats sustained over $ 50 million in losses while marinas sustained $ 25 million in damage. An aerial survey from

56444-442: The refinery were damaged, leaving the entire facility incapacitated. The control tower, associated weather instrumentation, and aircraft at the airport were badly damaged. A loose steel fuel tank collided into and destroyed a U.S. Customs shed. A UH-1 helicopter and two heavy trucks belonging to the National Guard were destroyed by debris. Less severe damage occurred in southwestern Saint Croix near Frederiksted . Rough surf damaged

56718-444: The release of latent heat from the saturated soil. Orographic lift can cause a significant increase in the intensity of the convection of a tropical cyclone when its eye moves over a mountain, breaking the capped boundary layer that had been restraining it. Jet streams can both enhance and inhibit tropical cyclone intensity by influencing the storm's outflow as well as vertical wind shear. On occasion, tropical cyclones may undergo

56992-451: The remnants of Hugo on the afternoon of September 22. In both Chardon and Medina , 4.3 in (110 mm) of rain fell in two hours. Floodwaters inundated urban areas and basements. In the eastern suburbs of Cleveland , flooding overtook cars and buses. High water and washouts forced the closure of U.S. Route 42 and Ohio State Route 94 in Medina County . The juxtaposition of Hugo's extratropical remnants (a low-pressure system) over

57266-429: The role of a scientific curiosity. Every spring, storm chasers head to the Great Plains of the United States and the Canadian Prairies to explore the scientific aspects of storms and tornadoes through use of videotaping. Radio pulses produced by cosmic rays are being used to study how electric charges develop within thunderstorms. More organized meteorological projects such as VORTEX2 use an array of sensors, such as

57540-452: The same area, resulting in devastating flash flooding . A similar event occurred in Boscastle , England, on 16 August 2004, and over Chennai on 1 December 2015. Each year, many people are killed or seriously injured by severe thunderstorms despite the advance warning . While severe thunderstorms are most common in the spring and summer, they can occur at just about any time of the year. Cloud-to-ground lightning frequently occurs within

57814-492: The same intensity. The passage of a tropical cyclone over the ocean causes the upper layers of the ocean to cool substantially, a process known as upwelling , which can negatively influence subsequent cyclone development. This cooling is primarily caused by wind-driven mixing of cold water from deeper in the ocean with the warm surface waters. This effect results in a negative feedback process that can inhibit further development or lead to weakening. Additional cooling may come in

58088-441: The same system. The ASCAT is a scatterometer used by the MetOp satellites to map the wind field vectors of tropical cyclones. The SMAP uses an L-band radiometer channel to determine the wind speeds of tropical cyclones at the ocean surface, and has been shown to be reliable at higher intensities and under heavy rainfall conditions, unlike scatterometer-based and other radiometer-based instruments. The Dvorak technique plays

58362-513: The sea can result in heat being inserted in deeper waters, with potential effects on global climate . Vertical wind shear decreases tropical cyclone predicability, with storms exhibiting wide range of responses in the presence of shear. Wind shear often negatively affects tropical cyclone intensification by displacing moisture and heat from a system's center. Low levels of vertical wind shear are most optimal for strengthening, while stronger wind shear induces weakening. Dry air entraining into

58636-416: The seas from 8 to 10 ft (2.4 to 3.0 m) above mean sea level . Telecommunications were knocked out by the storm throughout Guadeloupe as winds brought down power and telephone lines. Three thousand houses, predominantly wooden shanties, were unroofed. Approximately half of Pointe-a-Pitre , Guadeloupe's largest city, was destroyed. However, the storm's trajectory relative to Guadeloupe prevented

58910-526: The single-cell storm, yet much weaker than the supercell storm. Hazards with the multicell cluster include moderate-sized hail, flash flooding, and weak tornadoes. A squall line is an elongated line of severe thunderstorms that can form along or ahead of a cold front . In the early 20th century, the term was used as a synonym for cold front . The squall line contains heavy precipitation , hail , frequent lightning , strong straight line winds, and possibly tornadoes and waterspouts . Severe weather in

59184-487: The six meteorological offices of the Caribbean Meteorological Council. The first hurricane watch was issued by the NHC at 09:00 UTC on September 15, covering much of the Lesser Antilles from Saint Lucia northward to the British Virgin Islands . The watch was escalated to a hurricane warning three hours later. Concurrent watches and warnings for tropical storm conditions were in effect for Saint Vincent and Barbados . These initial alerts were discontinued following

59458-540: The southern portions of Ontario. The remnants of Hugo tracked northeastward and entered the Canadian province of Quebec . In Montreal , rainfall reached only 0.43 in (11 mm), while precipitation amounts in the province peaked at 3.73 in (95 mm). In addition to light rain, high winds were reported in the province. Winds in Montreal gusted up to 59 mph (95 km/h), leaving 13,400 homes without electricity. 7,400 residence in Verdun and West Island also lost electricity when tree fell on power lines; it

59732-478: The state (and the continental United States) was 10.28 in (261 mm) as measured in Edisto Island . Totals between 4–6 in (100–150 mm) were commonplace along the coast of South Carolina. The South Carolina Electric and Gas Company (SCE&G) called Hugo "the single greatest natural disaster ever to strike the state", inflicting $ 5.9 billion in property damage. The hurricane's trajectory swept across three major South Carolina cities. According to

60006-428: The state. In western parts of Massachusetts, some apple orchards reported damage to as much as 30 percent of their crops. In Vermont , the high winds generated swells several feet high on Lake Champlain , freeing some boats from their moorings. Trees and power lines were also brought down by the winds statewide. After becoming extratropical, the remnants of Hugo entered Canada into the province of Ontario . In

60280-553: The state. The Red Cross documented the destruction of 3,307 single-family homes and "major damage" to another 18,171. Across eight counties, manufacturers incurred $ 158 million in damage to factories and $ 750 million in inventory and income losses. Much of the South Carolina coast was subject to the ferocity of the hurricane's forces. Hugo's storm surge wrecked the barrier islands , thoroughly razing many structures. Many homes on Wadmalaw Island and Johns Island were crushed by fallen trees. The Ben Sawyer Bridge connecting

60554-489: The state. This quantity of timber was enough to build 660,000 homes. The total stock of growing softwood was cut by 21 percent while the total stock of growing hardwood fell by 6 percent. Hugo was widely considered the most significant forest disaster in South Carolina history. Across 23 counties, 4.4 million acres (1.8 million hectares) experienced the loss of 6.6 million board feet (15,600 m) of timber, equivalent to three to four times

60828-407: The storm and vegetation was stripped bare. Most houses on the island were razed or seriously damaged, displacing 11,000 of Montserrat's 12,000 residents. At least minor damage was dealt to nearly every building on the island, with severe damage inflicted on half of all buildings. Approximately ninety percent of homes suffered either major to total roof loss, with the most severe damage occurring in

61102-411: The storm in the Leeward Islands . Three thousand houses were unroofed, contributing to the displacement of 35,000 people from their homes. Hugo was Montserrat 's costliest hurricane on record and brought down the island's entire power grid. Ninety percent of homes on the island suffered significant to total roof loss after the island was struck by the eyewall . The hurricane's impacts continued into

61376-412: The storm substantially, its eye became ill-defined in satellite imagery and its winds had diminished to around 105 mph (165 km/h) by 06:00 UTC on September 19. However, the hurricane's return to open waters provided suitable conditions for reintensification. By this juncture, the broader weather patterns that steered Hugo had changed: the Azores High became a dominant influence north of

61650-463: The storm's passage by September 18. A hurricane watch was issued for Puerto Rico and the U.S. Virgin Islands on September 15; this was superseded by a hurricane warning the following day that in turn was lifted on September 19. As Hugo tracked northwest across the Sargasso Sea between September 19–20, tropical storm warnings were issued for coastal areas of the Dominican Republic and The Bahamas . The NHC first issued hurricane watches for portions of

61924-408: The storm, and only limited service was restored to businesses in December 1989. Some private residences in Saint Croix remained without telephone service until March 1990. Between 300–500 prisoners were freed from prison in Saint Croix after the storm, either by escaping or by release due to food and water shortages in the prison. The Federal Emergency Management Agency (FEMA) dispatched

62198-416: The storm. SCE&G reported that 300,000 of its electricity customers lost power, with a complete loss of power east of Interstate 95 . Utility services from the South Carolina Public Service Authority were crippled for 99 percent of the utility's customers. At Shaw Air Force Base near Sumter , 200 homes were destroyed and 1,000 sustained heavy damage; the property damage toll for Sumter County

62472-407: The storm; another 100 structures were threatened by coastal erosion. Along parts of the coast, 50 ft (15 m) of beach eroded, including sand dunes that once stood 7–8 ft (2.1–2.4 m) tall. Sixty percent of the sand dunes in Long Beach were eliminated by the hurricane, further exposing areas inland to the storm's fury. Several piers were wrecked by Hugo: the pier at Yaupon Beach

62746-411: The stricken island. The first contingent arrived in Saint Croix on the morning of September 21 to secure an airfield and devise the command structure for the other arriving troops. National Basketball Association player Tim Duncan , born in Christiansted and a two-time NBA MVP , of the San Antonio Spurs attributed his basketball career to Hurricane Hugo's destruction. When Tim was 13 years old, he

63020-563: The strongest and most severe. Mesoscale convective systems formed by favorable vertical wind shear within the tropics and subtropics can be responsible for the development of hurricanes . Dry thunderstorms , with no precipitation, can cause the outbreak of wildfires from the heat generated from the cloud-to-ground lightning that accompanies them. Several means are used to study thunderstorms: weather radar , weather stations , and video photography. Past civilizations held various myths concerning thunderstorms and their development as late as

63294-600: The strongest hurricane to strike the United States in 20 years. The ship Snow Goose , anchored in the Sampit River 5 mi (8.0 km) west of Georgetown , clocked a 120-mile-per-hour (193 km/h) sustained wind using an anemometer mounted on the ship's mast. In downtown Charleston , a sustained wind of 87 mph (140 km/h) and a gust of 108 mph (174 km/h) were reported. Hugo produced an 8-foot (2.4 m) storm surge at Charleston, indicating that water levels rose 12.9 ft (3.9 m) above mean lower low water as Hugo made landfall. Elsewhere along

63568-443: The strongest type of thunderstorm. In the United States, a thunderstorm is classed as severe if winds reach at least 93 kilometres per hour (58 mph), hail is 25 millimetres (1 in) in diameter or larger, or if funnel clouds or tornadoes are reported. Although a funnel cloud or tornado indicates a severe thunderstorm, a tornado warning is issued in place of a severe thunderstorm warning . A severe thunderstorm warning

63842-419: The subtropical ridge position, shifts westward across the western Pacific Ocean, which increases the landfall threat to China and much greater intensity in the Philippines . The Atlantic Ocean experiences depressed activity due to increased vertical wind shear across the region during El Niño years. Tropical cyclones are further influenced by the Atlantic Meridional Mode , the Quasi-biennial oscillation and

64116-419: The surface pressure decreases by 2.5 hPa (0.074 inHg) per hour for at least 12 hours or 5 hPa (0.15 inHg) per hour for at least 6 hours. For rapid intensification to occur, several conditions must be in place. Water temperatures must be extremely high, near or above 30 °C (86 °F), and water of this temperature must be sufficiently deep such that waves do not upwell cooler waters to

64390-483: The surface. On the other hand, Tropical Cyclone Heat Potential is one of such non-conventional subsurface oceanographic parameters influencing the cyclone intensity. Wind shear must be low. When wind shear is high, the convection and circulation in the cyclone will be disrupted. Usually, an anticyclone in the upper layers of the troposphere above the storm must be present as well—for extremely low surface pressures to develop, air must be rising very rapidly in

64664-435: The system and its intensity. For example, within the Northern Atlantic and Eastern Pacific basins, a tropical cyclone with wind speeds of over 65  kn (120 km/h; 75 mph) is called a hurricane , while it is called a typhoon or a severe cyclonic storm within the Western Pacific or North Indian oceans. When a hurricane passes west across the International Dateline in the Northern Hemisphere, it becomes known as

64938-577: The television station below. Numerous trees in Charlotte were also blown down atop homes and power lines, triggering long-lasting power outages that affected 85 percent of Charlotte homes and businesses. A six-month-old boy was killed after a tree toppled onto his mobile home; another 15 people were injured, primarily by falling trees. The winds piled boats together and destroyed or damaged thousands of them in Lake Norman , located north of Charlotte. Wind damage in Mecklenburg County amounted to over $ 500 million. Millions of trees were felled across

65212-433: The territory amounted to $ 2 billion while Storm Data , a monthly publication from the National Centers for Environmental Information , estimated that damage reached $ 1 billion; property damage accounted for $ 900 million while crop damage accounted for $ 100 million. The outer rainbands of Hugo began moving across Puerto Rico at 5:00 p.m. AST (21:00 UTC) on September 17. Hugo made two landfalls in

65486-486: The thunderstorm cell. Any precipitation falls the long distance through the clouds towards the Earth's surface. As the droplets fall, they collide with other droplets and become larger. The falling droplets create a downdraft as it pulls cold air with it, and this cold air spreads out at the Earth's surface, occasionally causing strong winds that are commonly associated with thunderstorms. Thunderstorms can form and develop in any geographic location but most frequently within

65760-592: The thunderstorm's further growth. The downdraft hitting the ground creates an outflow boundary . This can cause downbursts, a potential hazardous condition for aircraft to fly through, as a substantial change in wind speed and direction occurs, resulting in a decrease of airspeed and the subsequent reduction in lift for the aircraft. The stronger the outflow boundary is, the stronger the resultant vertical wind shear becomes. There are four main types of thunderstorms: single-cell, multi-cell, squall line (also called multi-cell line) and supercell. Which type forms depends on

66034-408: The topography of the Appalachian Mountains led to a localized area of heavier rainfalls , resulting in 6 in (150 mm) rainfall totals. While Hugo's rainfall was not sufficient to cause major river flooding in North Carolina, minor flooding impacted mountainous areas north and east of Asheville and highways in seven counties. A nursing home in Boone, North Carolina , was evacuated following

66308-527: The transport. The total cost of repairs on the island was estimated at over € 610 million. Two days after Hugo's passage, an Aérospatiale SA 330 Puma rescue helicopter crashed in La Désirade, killing nine people. The Guadeloupe government held a competition to design homes that would be quickly built to house the island's homeless population; five of thirty models were selected, and the first homes were built five months after Hugo. The banana industry in Guadeloupe required FF 466 million to recover, while

66582-423: The tropical cyclone year begins on July 1 and runs all year-round encompassing the tropical cyclone seasons, which run from November 1 until the end of April, with peaks in mid-February to early March. Of various modes of variability in the climate system, El Niño–Southern Oscillation has the largest effect on tropical cyclone activity. Most tropical cyclones form on the side of the subtropical ridge closer to

66856-461: The two, Culebra experienced stronger winds and heavier damage. The devastation in both islands was nonetheless thorough and widespread. Hurricane reconnaissance observations and the resulting damage in Culebra suggested that the island was struck by 150-mph (240 km/h) wind gusts. Southeasterly winds were accelerated by the hills on the sides of Ensenada Honda . The homes of 80 percent of Culebra residents were wrecked. A housing development near

67130-552: The updraft is strong enough, the droplets are held aloft long enough to become so large that they do not melt completely but fall as hail . While updrafts are still present, the falling rain drags the surrounding air with it, creating downdrafts as well. The simultaneous presence of both an updraft and a downdraft marks the mature stage of the storm and produces cumulonimbus clouds. During this stage, considerable internal turbulence can occur, which manifests as strong winds, severe lightning, and even tornadoes . Typically, if there

67404-464: The various monsoon seasons around the globe, and they populate the rainbands of tropical cyclones . In temperate regions, they are most frequent in spring and summer, although they can occur along or ahead of cold fronts at any time of year. They may also occur within a cooler air mass following the passage of a cold front over a relatively warmer body of water. Thunderstorms are rare in polar regions because of cold surface temperatures. Some of

67678-539: The warm season between spring and fall. More intense systems form over land than over water. One exception is that of lake-effect snow bands, which form due to cold air moving across relatively warm bodies of water, and occurs from fall through spring. Polar lows are a second special class of MCS. They form at high latitudes during the cold season. Once the parent MCS dies, later thunderstorm development can occur in connection with its remnant mesoscale convective vortex (MCV). Mesoscale convective systems are important to

67952-454: The water vapor condenses into liquid, latent heat is released, which warms the air, causing it to become less dense than the surrounding, drier air. The air tends to rise in an updraft through the process of convection (hence the term convective precipitation ). This process creates a low-pressure zone within and beneath the forming thunderstorm. In a typical thunderstorm, approximately 500 million kilograms of water vapor are lifted into

68226-451: The weaker of two tropical cyclones by reducing the organization of the system's convection and imparting horizontal wind shear. Tropical cyclones typically weaken while situated over a landmass because conditions are often unfavorable as a result of the lack of oceanic forcing. The Brown ocean effect can allow a tropical cyclone to maintain or increase its intensity following landfall , in cases where there has been copious rainfall, through

68500-438: The west-northwest with its forward speed decelerating. At 18:00  UTC on September 15, the first aircraft reconnaissance mission to probe Hugo reported that it had intensified to a Category 5 hurricane with maximum sustained winds of 160 mph (260 km/h) and a minimum central barometric pressure of 918 mbar (27.11 inHg), which turned out to be its peak intensity. Still several hundred miles east of

68774-463: The wharf at Pointe-à-Pitre estimated a gust of 184 mph (296 km/h). Rainfall totals ranged from 3.1 inches (79 mm) along the southern part of Guadeloupe to 13.8 inches (350 mm) in more mountainous areas. Hourly rainfall rates averaged roughly 2 inches (51 mm) per hour in the core of the hurricane. A station in Gardel documented 3.66 inches (93 mm) of rain in one hour. Along Grand Cul-de-Sac Marin, storm surge from Hugo elevated

69048-402: The wind speed of Hurricane Helene by 11%, it increased the destruction from it by more than twice. According to World Weather Attribution the influence of climate change on the rainfall of some latest hurricanes can be described as follows: Tropical cyclone intensity is based on wind speeds and pressure. Relationships between winds and pressure are often used in determining the intensity of

69322-702: The world, over half of which develop hurricane-force winds of 65  kn (120 km/h; 75 mph) or more. Tropical cyclones typically form over large bodies of relatively warm water. They derive their energy through the evaporation of water from the ocean surface, which ultimately condenses into clouds and rain when moist air rises and cools to saturation . This energy source differs from that of mid-latitude cyclonic storms , such as nor'easters and European windstorms , which are powered primarily by horizontal temperature contrasts . Tropical cyclones are typically between 100 and 2,000 km (62 and 1,243 mi) in diameter. The strong rotating winds of

69596-447: Was $ 237 million. The effects of Hugo in the Carolinas were most fatal in Berkeley County, where eight people were killed. Over a thousand homes and apartments were destroyed and 70–80 percent of the county's trees were blown down. Up to a quarter of York County 's cotton crop was lost, with additional losses suffered by peach, sorghum, and soybean crops. Across North Carolina, Hugo damaged 2,638 structures and destroyed 205;

69870-659: Was 185 kn (95 m/s; 345 km/h; 215 mph) in Hurricane Patricia in 2015—the most intense cyclone ever recorded in the Western Hemisphere . Warm sea surface temperatures are required for tropical cyclones to form and strengthen. The commonly-accepted minimum temperature range for this to occur is 26–27 °C (79–81 °F), however, multiple studies have proposed a lower minimum of 25.5 °C (77.9 °F). Higher sea surface temperatures result in faster intensification rates and sometimes even rapid intensification . High ocean heat content , also known as Tropical Cyclone Heat Potential , allows storms to achieve

70144-472: Was a Cape Verde hurricane that developed from a cluster of thunderstorms associated with a tropical wave first observed moving off the coast of Africa on September 9, near Cape Verde . (part of that same wave would later spawn Hurricane Raymond in the eastern Pacific ). A tropical depression developed from this disturbance roughly 125 mi (200 km) south of Cape Verde the following day. The nascent cyclone intensified as it tracked west along

70418-423: Was a competitive swimmer who was considered one of the top United States competitors for the 400-meter freestyle. However, in the aftermath of Hugo, every swimming pool on Saint Croix was destroyed, including the Olympic-size swimming pool. With no pool to practice in, Duncan turned to basketball. Tim Duncan said, "I'm very fortunate to be where I am today. Without Hugo, I might still be swimming." On April 4, 2020, it

70692-475: Was a slowdown in tropical cyclone translation speeds. It is unclear still to what extent this can be attributed to climate change: climate models do not all show this feature. A 2021 study review article concluded that the geographic range of tropical cyclones will probably expand poleward in response to climate warming of the Hadley circulation . When hurricane winds speed rise by 5%, its destructive power rise by about 50%. Therfore, as climate change increased

70966-410: Was announced that Duncan would be inducted into the Naismith Memorial Basketball Hall of Fame on August 29. Tropical cyclone A tropical cyclone is a rapidly rotating storm system with a low-pressure center, a closed low-level atmospheric circulation , strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls . Depending on its location and strength,

71240-405: Was approximately $ 60 million, with over $ 40 million incurred in Carroll and Grayson County, Virginia counties; six people were killed statewide. While Hugo's quick traversal of the Southeastern U.S. enlarged the area of inland wind damage, it also attenuated rainfall totals; rainfall was relatively light for a storm of Hugo's size. In southwestern Virginia and western North Carolina,

71514-470: Was at the epicenter of Hugo's devastation. At McClellanville, near the point of maximum storm surge, shrimp boats were pushed as far as 0.5 mi (0.80 km) inland. Commercial and recreational craft damaged other structures as they were carried ashore. A high school used as a shelter for 1,125 local residents was inundated by the ocean's advance; documentation had listed its elevation 11 ft (3.4 m) too high, leading to its mistaken selection as

71788-426: Was buffeted with winds of 40–50 mph (64–80 km/h), blowing down some trees and branches. This led to scattered and brief power outages that affected 30,000 electricity customers. Total property and crop damage in Connecticut amounted to at least $ 50,000. Power outages also affected thousands of electricity customers in Massachusetts . Fallen trees and broken limbs caused scattered property damage throughout

72062-434: Was destroyed while a fourth of the pier at Long Beach was lost; the end of the pier at Holden Beach also succumbed to the storm. With the aid of Hugo's rapid forward motion, the swath of damaging winds produced by Hugo in interior South Carolina penetrated into western North Carolina while still a category 1 hurricane and brought extensive damage to areas that rarely experienced impacts from tropical cyclones. Hugo produced

72336-401: Was documented on 1,500 homes and total loss was documented on 106. Thirty percent of fishing vessels were also damaged by the hurricane, equating to thousands of boats. The total cost of damage reached nearly EC $ 200 million. Hugo's damage toll in Saint Kitts and Nevis amounted to $ 46 million, largely sustained by shoreline structures and crops. This equated to 32 percent of

72610-432: Was estimated by the U.S. Forest Service at between $ 95–115 million. Animals, including some from endangered species , were killed at Cape Romain National Wildlife Refuge . However, the lack of infrastructure near the refuge significantly reduced the damage wrought by Hugo's strongest winds. Coastal impacts in South Carolina were extensive beyond Charleston County. The waterfront in Georgetown suffered heavily, with

72884-436: Was evacuated for the first time in living memory. Hundreds of evacuees were brought to a stadium in Mayagüez . The Luis Muñoz Marín International Airport terminated all scheduled flights at 6 p.m. AST on September 17. All international airlines evacuated their aircraft from Puerto Rico, though one Airbus A300 owned by American Airlines was left behind for emergency use. Tourists left en masse on departing flights before

73158-525: Was prepositioned throughout Myrtle Beach, South Carolina , to expedite cleanup operations. The mayor of Charleston, Joseph P. Riley Jr. , called Hugo "an extraordinarily dangerous event, [...] the likes of which few people who have lived all their lives in Charleston have experienced." Twenty U.S. Navy ships and submarines were moved out of Charleston to weather the storm at sea. The New Georgia Railroad between Atlanta and Savannah, Georgia, halted operations, affecting 400 passengers. The hurricane watch for

73432-484: Was recorded along the lower Río Blanco. Flooding was mostly limited to the northeastern corner of Puerto Rico and in San Juan where rainfall was heaviest. In these areas, over 10 in (250 mm) of rain fell in 48 hours. The heavy rainfall drained into the Fajardo River and Mameyes River , causing them to set new records for discharge rates; three other rivers reached discharge rates within 10–15 percent of their highest on record. Flash floods occurred near

73706-402: Was restored about 12 hours later. While in Brossard and Chambly , power was lost to 5,000 homes and 1,000 homes in Valleyfield . In addition, high winds and heavy rainfall also occurred in the St. Lawrence River Valley . Similar effects were reported in New Brunswick , though little rainfall occurred in the province. Winds gusting to 77 mph (124 km/h) was reported in Moncton . As

73980-474: Was revived in the latter part of World War II for the Western Pacific. Formal naming schemes have subsequently been introduced for the North and South Atlantic, Eastern, Central, Western and Southern Pacific basins as well as the Australian region and Indian Ocean. At present, tropical cyclones are officially named by one of twelve meteorological services and retain their names throughout their lifetimes to provide ease of communication between forecasters and

74254-570: Was sent to Guadeloupe from Paris on September 19, with two more relief aircraft held on standby. The crews were tasked with sheltering the homeless, restoring electricity service, and clearing roads. Doctors were also sent to Guadeloupe from La Meynard Hospital in Martinique. Emergency supplies from Paris were gathered by Catholic Air and Red Cross . Military aircraft delivered 50 tons (45 tonnes) of supplies and over 500 emergency workers to Guadeloupe, along with Minister of Overseas France Louis Le Pensec ; 3,000 soldiers also accompanied

74528-523: Was the strongest storm to traverse the northeastern Caribbean since Hurricane David in 1979 . The Sea, Lake, and Overland Surge from Hurricanes (SLOSH) model estimated that storm surge from Hugo led to coastal water levels 3–4 ft (0.91–1.22 m) above normal tidal heights along Saint Croix and the eastern end of Puerto Rico. These equated to storm surge heights of around 7–8 ft (2.1–2.4 m). Water levels of 2–3 ft (0.61–0.91 m) above normal were estimated to have occurred along

74802-492: Was ultimately less than forecast. Power distribution systems in San Juan and other communities were severely crippled, leading to power outages affecting thirty-five municipalities. Many power poles in Puerto Rico held a disproportionate number of electrical conductors , resulting in greater power loss than would otherwise be expected for the conditions experienced. A destroyed communications antenna in El Yunque National Forest cut off communication to Vieques and Culebra. Debris in

75076-427: Was unable to stop widespread looting, with armed gangs reportedly taking root the streets of Christiansted. The Atlanta Constitution reported that some members of the local police and National Guard also took part in looting. For the first time since the Baltimore riot of 1968 , American troops were deployed in response to a domestic civil disturbance; with the authorization of U.S. President George H. W. Bush under

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