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Hurricane Humberto was a minimal hurricane that formed and intensified faster than any other North Atlantic tropical cyclone on record before landfall. Developing on September 12, 2007, in the northwestern Gulf of Mexico, the tropical cyclone rapidly strengthened and struck High Island, Texas, with winds of about 90 mph (150 km/h) early on September 13. It steadily weakened after moving ashore, and on September 14 it began dissipating over northwestern Georgia as it interacted with an approaching cold front. Damage was fairly light, estimated at approximately $50 million (2007 USD). Precipitation peaked at 14.13 inches (358.9 mm), while wind gusts to 85 mph (137 km/h) were reported. The heavy rainfall caused widespread flooding, which damaged or destroyed dozens of homes, and closed several highways. Trees and power lines were downed, knocking out power to hundreds of thousands of customers. The hurricane caused one fatality in the State of Texas. Additionally, as the storm progressed inland, rainfall was reported throughout the Southeast United States. ==Meteorological history== The origins of Humberto are from the remnants of a frontal trough—the same that spawned Tropical Storm Gabrielle—that moved offshore south Florida on September 5. The combination of a weak surface trough and an upper-level low pressure system produced disorganized showers and thunderstorms from western Cuba into the eastern Gulf of Mexico. Tracking slowly west-northwestward, unfavorable wind shear initially inhibited tropical cyclone development. By late on September 11, environmental conditions became more favorable, and the following morning convection increased over the disturbance. Tracking around the western periphery of a mid-level ridge, the system turned on a slow northwest drift and quickly organized. Radar imagery reported loose banding features, and buoy data indicated the presence of a surface circulation; based on the observations, the National Hurricane Center classified the system as Tropical Depression Nine, while located roughly 60 miles (100 km) southeast of Matagorda, Texas. Upon becoming a tropical cyclone, the depression was forecast to strengthen slowly to reach peak winds of 45 mph (75 km/h).〔 Within three hours of forming, the depression intensified into Tropical Storm Humberto. A small cyclone, the storm continued to organize quickly as it turned north-northeastward, while radar imagery suggested the formation of an eye by early on September 13. Based on reports from Hurricane Hunters, Humberto was upgraded to a hurricane at 0515 UTC on September 13, while located about 15 miles (20 km) off the coast of Texas. The hurricane made landfall a few miles to the east of High Island at around 0700 UTC. A well-defined eye was maintained with strong convection around it, and Hurricane Hunters reported sustained winds of 85 mph (140 km/h) about two hours after landfall. However, post-storm analysis later determined that the winds were a bit stronger—about 90 mph (150 km/h).〔 Based on operational estimates of a wind speed increase of 50 mph (85 km/h), the National Hurricane Center reported that "no tropical cyclone in the historic record has ever reached this intensity at a faster rate near landfall." The path of the eye continued northeastward and passed over Port Arthur, Nederland, Port Neches, Groves, and Bridge City, Texas at Category 1 hurricane strength. This was the second time within two years (following Hurricane Rita on September 24, 2005) that these cities experienced a direct hit from a hurricane. By eight hours after landfall, Humberto weakened to a tropical storm as it crossed into southwestern Louisiana. Increased upper-level wind shear caused the storm to weaken rapidly over land, and late on September 13 Humberto weakened to a tropical depression. Upon issuing its last advisory, the National Hurricane Center remarked on the potential for the remnants of the storm to turn southward into the Gulf of Mexico. However, the storm continued northeastward through the southeastern United States, and on September 14, the storm began dissipating over northwestern Georgia, and shortly thereafter degenerated into a remnant low pressure area. 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 Humberto (2007)」の詳細全文を読む スポンサード リンク
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