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Hurricane Alex was a rare June hurricane and the first tropical cyclone to develop in the 2010 Atlantic hurricane season. Originating from an area of disturbed weather on June 25, 2010, it slowly developed in the western Caribbean Sea and struck Belize as a strong tropical storm. After entering the Gulf of Mexico, Alex became very large and encountered conditions favorable for gradual development. Early on June 30, the cyclone attained hurricane status as it approached northeastern Mexico, the first June hurricane in the Atlantic basin since Hurricane Allison in 1995, and the storm rapidly intensified just off the coast of Tamaulipas. Alex came ashore near Soto la Marina as a Category 2 hurricane on the Saffir-Simpson Hurricane Wind Scale. Alex caused the deaths of at least 51 people along its path, and produced over $1.8 billion (2010 USD) in damage. The precursor of the hurricane produced substantial rainfall across the Greater Antilles, causing one death in the Dominican Republic. Fourteen people were killed in Central America as a result of flooding during the first landfall of Alex. In Mexico, the storm's outer rainbands killed three people in Acapulco, one person in Oaxaca, and another in Chiapas. At its final landfall, Alex caused at least fifteen deaths in Nuevo León, eight in Coahuila, six in Guanajuato, and one in both Tamaulipas and San Luis Potosí; an additional twenty persons were reported missing. Alex triggered widespread power outages throughout northeastern Mexico and southern Texas. Damage was most evident in the Monterrey metropolitan area, which faced what Nuevo León governor Rodrigo Medina de la Cruz described as, "the worst weather phenomenon in its history."〔 Following Alex's final landfall, a state of emergency was declared for most of Nuevo León, portions of Tamaulipas, and Texas. Widespread flooding from the storm affected 500,000 people throughout northeast Mexico, and ruined over of crops in the region, equivalent to 11% of the region's total farmland. ==Meteorological history== The weather system from which Hurricane Alex developed was first discernible as a disturbance in the Intertropical Convergence Zone (ITCZ) on June 17, 2010. Over the next few days, most of its associated thunderstorm activity was embedded within the ITCZ. The National Hurricane Center (NHC) first mentioned it as a candidate for tropical cyclone formation on June 20, while it was crossing the Windward Islands into the southeastern Caribbean Sea; at the time, some upper-level wind shear was present, leading to conditions only marginally favorable for development. The system moved through the Caribbean, and on June 21, it developed to the extent that the NHC assessed a 50% chance of development into a tropical depression within 48 hours. The next day, however, the feature deteriorated as thunderstorm activity spread across the Greater Antilles, although the upper-level regime remained favorable for eventual redevelopment. On June 24, a low-level circulation had gradually become better established to the south of Jamaica, although it was displaced from its poorly organized convection. By 1800 UTC, a surface low-pressure area had formed about 105 miles (165 km) to the northeast of Cabo Gracias a Dios, Nicaragua, but due to a lack of persistent thunderstorm activity, it was not yet considered a tropical cyclone.〔 Later that day, convection increased over the center of circulation, and atmospheric pressures dropped across the region. Late on June 25, Hurricane Hunters verified the development of a surface low pressure area, which, combined with the increase of thunderstorm activity, indicated the system was a tropical depression. Accordingly, the cyclone was classified as Tropical Depression One at 2200 UTC, while located about 345 miles (555 km) to the east-southeast of Chetumal, Quintana Roo. After the end of the hurricane season, the National Hurricane Center revised their analysis and estimated that the system had actually become a tropical depression at around 1800 UTC.〔 At the time of its formation, the depression was moving to the west-northwest, steered by a high pressure system over the northern Gulf of Mexico. An anticyclone positioned over the storm created an environment of minimal wind shear, and the depression quickly intensified. At 0900 UTC on June 26, it obtained tropical storm status and was given the name ''Alex''. As Tropical Storm Alex progressed through the western Caribbean Sea towards the Yucatán Peninsula, it developed a large field of clouds accompanied by well-established outflow throughout its circulation. Its inner structure was initially disorganized, although by late on June 26, it became better defined. At about 2100 UTC, as the tropical storm approached the Belize coast, a Hurricane Hunters flight reported winds of 65 mph (100 km/h); early on June 27, Alex made landfall just north of Belize City at this intensity. Upon moving ashore, an area of convection increased over the center, and the convection initially became better defined as it crossed the Yucatán Peninsula. While most tropical cyclones weaken and become disorganized after landfall, Alex seemed to become stronger when viewed on radar and satellite imagery—the National Hurricane Center noted in one of its forecast discussions that the cyclone's structure more closely resembled a hurricane than a deteriorating storm. Still, after enough time over land, convective activity markedly decreased, and Alex weakened to tropical depression status as it approached the peninsula's western coastline. Late on June 27, the depression emerged into the Gulf of Mexico with a large overall convective structure but little thunderstorm activity near the center due to the interaction with land. When Alex was still located over the Yucatán Peninsula, the NHC remarked upon the potential for significant strengthening. Because of low wind shear and very warm water temperatures in the Gulf of Mexico, the possibility existed that Alex could intensify into a major hurricane—a Category 3 storm on the Saffir-Simpson Hurricane Wind Scale—before its next landfall.〔 Early on June 28, thunderstorm activity had reformed over the center, and the depression re-intensified into a tropical storm. For the next day, the combination of dry air, increasing wind shear and slightly cooler water temperatures prevented significant convection from developing over the center. At the same time, Alex was moving slowly off the northwest coast of the Yucatán Peninsula, and the environment's conditions became more favorable for intensification as the tropical storm tracked away from the coast. The circulation envelope of Alex remained very large, and by June 29, the storm's rainbands covered the entire western half of the Gulf of Mexico; rainfall was reported along the Texas and Louisiana coasts, even while the center was still several hundred miles offshore. The tropical storm continued to strengthen, and based on reports from Hurricane Hunters, it is estimated that Alex attained hurricane status at 0300 UTC on June 30, about 255 miles (415 km) southeast of Brownsville, Texas. Upon becoming a hurricane, Alex was located in a moist, low shear environment, which led to steady intensification on June 30. The pressure continued to fall—a sign of an intensifying cyclone—with a more rapid drop occurring that afternoon and evening. The hurricane strengthened into a Category 2 storm late on June 30 as it approached the northeastern Mexican coast. At 0200 UTC on July 1, Alex made landfall at peak strength, with maximum sustained winds of 105 mph (165 km/h), gusts of 125 mph (205 km/h) and an unusually low central pressure of in the municipality of Soto la Marina in the Mexican state of Tamaulipas. After the storm, the National Hurricane Center revised the landfall intensity estimate, showing Alex was even stronger when it struck the Mexican coast, with sustained winds of 110 mph (175 km/h) and a central pressure of .〔 Several hours after moving ashore, the storm weakened to Category 1 status, and its structure began to deteriorate. However, deep convection persisted around the center. By 1200 UTC, Alex had weakened into a tropical storm; by 0000 UTC July 2, the Sierra Madre Oriental disrupted Alex's core, causing the storm to weaken into a tropical depression and dissipate over San Luis Potosí.〔 However, the interaction with the mountain range caused orographic lift on the eastern side of the storm after the center of circulation had ceased to exist, producing torrential rainfall throughout northern and central Mexico.〔 Following the dissipation of Alex, divergence at the 200 mb atmospheric pressure level (approximately at of altitude), a ridge of high pressure located over southern Texas, and Alex's residual moisture interacted to produce intense convection over Nuevo León, Tamaulipas and Coahuila for the next 72 hours.〔 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 Alex (2010)」の詳細全文を読む スポンサード リンク
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