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Hurricane Maria was a Category 1 hurricane that made landfall on the island of Newfoundland during September 2011. Originating from a tropical wave over the central Atlantic on September 6, Maria moved toward the west and slowly strengthened. While approaching the northern Leeward Islands, however, the system entered a region of higher vertical wind shear and cooler sea surface temperatures, causing it to degenerate into a low-pressure area. It slowly curved toward the north and northeast around the western periphery of the subtropical ridge, and regained tropical storm status on September 10. Maria further strengthened to attain hurricane status while making its closest approach to Bermuda. The cyclone attained peak winds of 80 mph (130 km/h) on September 16, but weakened thereafter due to an increase in wind shear and cooler sea surface temperatures. Maria made landfall on the southeastern coast of Newfoundland during the afternoon hours of September 16 before becoming absorbed by a frontal system later on that same day. Despite its poor organization, Maria brought heavy rainfall to portions of the east Caribbean, notably Puerto Rico. Numerous roadways and homes were flooded, and as the storm passed through the extreme northeastern Caribbean, over 15,000 people went without power. In addition, tropical storm-force winds were observed on many of the U.S. Virgin Islands. As the system passed west of Bermuda, brief tropical storm-force sustained winds were recorded, along with higher gusts; rainfall on the island, however, was minimal. In Newfoundland, strong winds were recorded, but rainfall totals were relatively minimal. There were no deaths reported in association with Maria, although the storm caused $1.3 million (2011 USD) in damage. ==Meteorological history== The origins of Hurricane Maria can be traced back to a tropical wave—an elongated area of low pressure oriented north to south—that moved westward from Nigeria to Senegal on September 1. The wave entered the eastern tropical Atlantic early the following day and slowly strengthened. By September 6, it had developed a sufficient amount of convection to be designated as Tropical Depression Fourteen, while it was about 700 mi (1100 km) west-southwest of the southern Cape Verde Islands. By this time, it had also developed well-established outflow within the western semicircle of the low-pressure center. The depression continued to increase in strength, and it was upgraded to a tropical storm six hours after formation, receiving the name Maria.〔 Early on September 7, the National Hurricane Center (NHC) noted that although Maria was in an area of favorable atmospheric conditions, most intensity guidance models did not anticipate any strengthening. The system changed little in organization over the next 24 hours as it moved rapidly toward the west-northwest around the southern periphery of the subtropical ridge. Though visible satellite imagery depicted a well-organized circulation center, it was displaced from the strongest convection due to increased vertical wind shear. The system reached an initial peak intensity with maximum sustained winds of 50 mph (85 km/h) on September 8 before the unfavorable environment began to impede the system's organization. Following a reconnaissance flight into the system early on September 9, it was noted that Maria had degenerated into a non-tropical disturbance, despite reports of tropical storm-force winds in the northern Leeward Islands.〔 Operationally, however, the NHC kept the system classified as a tropical cyclone and never downgraded it to a disturbance. When the system approached the northern Leeward Islands on September 10, satellite imagery and surface observations revealed an increase in its organization; a subsequent reconnaissance aircraft into the disturbance revealed that the remnants of Maria had regenerated into a tropical cyclone about 40 mi (65 km) east-southeast of Antigua.〔 After reaching the southwestern periphery of the subtropical ridge, Maria turned to the north as its forward motion slowed considerably. Strong vertical wind shear over the system began to relax by September 14, allowing Maria to slowly restrengthen as the convection redeveloped near its center. At 1800 UTC on September 15, Maria reached Category 1 hurricane status on the Saffir–Simpson Hurricane Scale while located roughly 135 mi (215 km) northwest of Bermuda.〔 Embedded within increasing atmospheric flow, the hurricane's forward motion accelerated towards the northeast. At 0000 UTC on September 16, Maria attained its peak intensity with winds of 80 mph (130 km/h) and a minimum barometric pressure of 983 mbar (29.03 inHg). Continuing on a northeastward course, Maria began to move over an area with cooler sea surface temperatures and higher vertical wind shear. Around 1800 UTC, Maria weakened to a tropical storm and made landfall near Cape St. Mary's, Newfoundland at 1830 UTC with winds of 70 mph (110 km/h). Shortly thereafter, the cyclone's circulation was absorbed by a frontal system over the Avalon Peninsula of Newfoundland.〔 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 Maria (2011)」の詳細全文を読む スポンサード リンク
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