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Hurricane Gonzalo was a powerful Atlantic tropical cyclone that wrought destruction in the Leeward Islands and Bermuda in October 2014. At the time, it was the strongest hurricane in the Atlantic since Igor in 2010, Gonzalo struck Bermuda less than a week after the surprisingly fierce Hurricane Fay; 2014 was the first season in recorded history to feature two hurricane landfalls on Bermuda. Gonzalo formed from a tropical wave on October 12, while located east of the Lesser Antilles. It made landfall on Antigua, Saint Martin, and Anguilla as a Category 1 hurricane, causing damage on those and nearby islands. Antigua and Barbuda sustained US$40 million in losses, and boats were abundantly damaged or destroyed throughout the northern Leeward Islands. The storm killed three people on Saint Martin and Saint Barthélemy. Gonzalo tracked northwestward as it intensified into a Category 4 major hurricane, the first in the Atlantic since Ophelia in 2011. Eyewall replacement cycles led to fluctuations in the hurricane's structure and intensity, but on October 16, Gonzalo peaked with maximum sustained winds of 145 mph (230 km/h). After Hurricane Fay caused extensive power outages on the island just days before, residents of Bermuda were forced to complete preparations for Gonzalo in haste. Banks, businesses, schools, and government offices closed in advance of the storm, while the Royal Navy ship HMS ''Argyll'' left its post in the Caribbean to provide Bermuda with emergency assistance. The cyclone gradually weakened before crossing directly over central Bermuda at Category 2 strength around 00:30 UTC on October 18. Gonzalo battered the island with wind gusts as high as 144 mph (232 km/h), downing hundreds of trees and creating widespread roof damage. At the height of the storm, about 31,000 out of 36,000 total electricity customers were without power; service was not fully restored until early November. Many roads were impassable immediately following the hurricane, and in many cases the damage done by Gonzalo was indistinguishable from that of Fay. Bermuda Regiment soldiers and sailors from the ''Argyll'' took part in initial cleanup and repairs on the territory, and preliminary assessments revealed that the storm did not compare to the devastation of Hurricane Fabian in 2003. Catastrophe modelling firms estimated that Bermuda suffered up to $400 million in losses, and despite the heavy disruptions, no deaths or serious injuries were reported there. Departing Bermuda, Gonzalo accelerated toward the waters of the North Atlantic, passing close to southeastern Newfoundland before becoming extratropical on October 19. Gusty winds and bands of heavy rain in the southeastern Avalon Peninsula engendered minor flooding and power outages. A large storm system involving the remnants of Gonzalo battered the British Isles and central Europe on October 21, killing three people in the United Kingdom and severely hindering transportation. The system later played a role in triggering torrential rains over the Balkans, which resulted in severe flooding in Greece and Bulgaria. ==Meteorological history== Hurricane Gonzalo originated in a tropical wave that emerged from the western coast of Africa on October 4 and trekked across the Atlantic. Despite an attendant expanse of clouds and thunderstorms, hostile winds from an upper-level trough hindered cyclogenesis. On October 10, after encountering an eastward-propagating Kelvin wave, the system developed more concentrated convection. With conditions increasingly favorable for further development, the disturbance gradually became better organized, forming a small low pressure area by October 11. In turn, a tropical depression formed at 00:00 UTC on October 12, located approximately 390 mi (630 km) east of the Leeward Islands. Continued maturation amid warm waters and low wind shear yielded Tropical Storm Gonzalo 12 hours later.〔 Operationally, the National Hurricane Center (NHC) did not begin issuing advisories on the cyclone until midday on October 12, after a Hurricane Hunter flight into the system reported surface winds of 40 mph (65 km/h). A powerful ridge over the central Atlantic steered the nascent storm westward toward the Lesser Antilles.〔 Thunderstorm activity was strong near the center, although initially somewhat disorganized and asymmetric. However, a tight inner core soon took shape, and Gonzalo began to quickly intensify throughout the day on October 12. Following the appearance of an eye feature early the next day, the storm was upgraded to a Category 1 hurricane while located near Antigua in the eastern Caribbean. Shortly thereafter, the storm passed directly over the island.〔 The hurricane later struck Saint Martin and Anguilla, and skirted just north of the British Virgin Islands while continuing to intensify.〔 By that time, it was headed toward the northwest around the periphery of the aforementioned ridge. On October 14, the eye contracted to a diameter of 17 mi (28 km) and improved its satellite presentation. At 18:00 UTC, Gonzalo strengthened to a Category 3 major hurricane while located about 170 mi (270 km) north of San Juan, Puerto Rico.〔 Six hours later it became the first Category 4 hurricane in the Atlantic basin since Hurricane Ophelia in 2011. Subsequently, a concentric eyewall structure indicated an imminent eyewall replacement cycle, with the inner feature "about as small as it can get" according to the NHC. The eyewall replacement cycle briefly disrupted the storm's core, causing Gonzalo to weaken slightly, but upon completion on the evening of October 15, the system stabilized and resumed intensification. While moving northward early the next day, Gonzalo reached its peak intensity with winds of 145 mph (230 km/h) and a barometric pressure of 940 mbar (hPa; 27.76 inHg). By evening it had turned north-northeastward, ahead of an advancing trough over the eastern United States and in the wake of the receding ridge.〔 From the evening of October 16 through the next morning, the hurricane experienced further internal fluctuations as it approached Bermuda from the south-southwest. Concurrently, the storm began to weaken.〔 In particular, cloud tops around the hurricane warmed, and convection became less uniform, likely attributable to cooler waters and heightened wind shear. The hurricane was downgraded to Category 2 as the northern eyewall crossed Bermuda, and at about 00:30 UTC on October 18, the center of circulation passed directly over the island, signalling an official landfall. Along with Hurricane Fay, which struck Bermuda on October 12, this represented the first recorded instance of two hurricanes making landfall on the island within the same season.〔 Moving away from Bermuda, the hurricane continued to degrade, but showed signs of increased organization later on October 18. As Gonzalo accelerated northeastward at over , it passed about 50 miles (80 km) southeast of Newfoundland's Avalon Peninsula early on October 19.〔 In spite of sea surface temperatures below 50 °F (10 °C), the storm was able to maintain a central dense overcast and deep warm core. By 18:00 UTC, Gonzalo had finally succumbed to the cold environment and intense wind shear, completing its transition into a strong extratropical cyclone about northeast of Cape Race, Newfoundland. It sped east-northeastward until a frontal boundary absorbed it on October 20, to the south-southwest of Iceland. The resultant system brought stormy weather to the British Isles and parts of mainland Europe on October 21,〔 and later contributed to the formation of a large cut-off low. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hurricane Gonzalo」の詳細全文を読む スポンサード リンク
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