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Hurricane Elena was an unpredictable and damaging tropical cyclone that affected eastern and central portions of the United States Gulf Coast in late August and early September 1985. Threatening popular tourist destinations during Labor Day weekend, Elena repeatedly deviated from its forecast path, triggering evacuations of unprecedented extent. The hurricane wrought havoc to property and the environment between southwestern Florida and eastern Louisiana, though lesser effects were felt well beyond those areas. Elena developed on August 28 near Cuba, and after traveling lengthwise across the island with little impact, it entered the Gulf of Mexico and continued to strengthen. Initially projected to strike the central Gulf Coast, the hurricane unexpectedly veered toward the east on August 30, then stalled just 50 mi (80 km) west of Cedar Key, Florida. Despite predictions that Elena would continue eastward across Florida, the cyclone remained nearly stationary for about 48 hours, causing damage all along the eastern gulf with high winds and waves, before slowly moving northwest and ultimately making landfall near Biloxi, Mississippi, on September 2 as a Category 3 major hurricane. The storm quickly weakened upon moving ashore and dissipated on September 4. The hurricane's unpredictable shifts in direction created what was considered the largest peacetime evacuation in the nation's history. Evacuations occurred in sequence to follow the storm's forecast positions, and many residents and tourists along portions of the Gulf Coast were forced to leave twice in a matter of days. Preparations were generally timely and efficient, though accommodations and resources at storm shelters were stretched thin, and many refugees tried to return home against officials' orders. About 1.25 million people fled the storm in Florida alone, contributing to a region-wide total of nearly 2 million evacuees. Tropical cyclone warnings and watches were continuously issued and adjusted, and forecasters stressed the storm's destructive potential for days. Elena's slow movement off western Florida resulted in severe beach erosion and damage to coastal buildings, roads, and seawalls, especially to those of old or inadequate construction. Destruction was greatest near the shore and on islands such as Cedar Key and Dog Island, though tornadoes spawned by the hurricane swept through communities and mobile home parks well inland. The hurricane devastated the Apalachicola Bay shellfish industry, killing large quantities of oysters, destroying their reefs, and leaving thousands of workers unemployed. Farther west, Dauphin Island in Alabama endured wind gusts as high as and a significant storm surge. The island sustained some of the most significant damage inflicted by Elena, including several hundred damaged or demolished homes. The rest of the state's coast also sustained considerable damage, and the inland pecan and soybean crops were severely diminished in Alabama and Mississippi. Over 13,000 homes were damaged in Mississippi, and 200 were destroyed. Cities close to the Alabama border—including Pascagoula—experienced widespread damage to residences, schools, and businesses, and the community of Gautier was effectively isolated from the outside world. Several apparent but unconfirmed tornadoes appear to have exacerbated the damage in the Gulfport area. Wind damage extended into portions of eastern Louisiana. Overall, nine people died as a result of the hurricane: two in Texas due to drownings in rip currents, three in Florida, two in Louisiana, one in Arkansas, and one in a maritime accident in the Gulf of Mexico. Damage totaled about $1.3 billion,〔Monetary figures in 1985 USD, unless otherwise noted.〕 and power outages from the storm affected 550,000 people. In Elena's wake, President Ronald Reagan declared parts of Alabama, Mississippi, and Florida federal disaster areas, making storm victims eligible for financial aid and temporary housing. The name ''Elena'' was later retired from the cyclical list of Atlantic hurricane names because of the storm's effects. ==Meteorological history== The origins of Hurricane Elena trace to an easterly tropical wave that was first identified off the western coast of Africa on August 23, 1985. The system sped westward across the Atlantic at up to . Its rapid motion, combined with the presence of an unusually hostile Saharan Air Layer, prevented tropical cyclogenesis for several days. Driven by a strong subtropical ridge to its north, the wave quickly approached North America as it began to show signs of organization. At 00:00 UTC on August 28, the disturbance developed into a tropical depression while over the Windward Passage. The newly designated depression began to track west-northwestward over Cuba, which is known to disrupt tropical cyclone development. Despite that, its central barometric pressure continued to deepen, and reconnaissance aircraft found winds exceeding near the center. In response, the National Hurricane Center upgraded the depression to Tropical Storm Elena over northern Cuba later on August 28. After passing north of Havana, Cuba, Elena emerged into the Gulf of Mexico. At 12:00 UTC on August 29, Elena intensified into a Category 1 hurricane.〔 Analysis of steering currents through the morning of August 30 suggested that Elena would continue on its northwestward track, striking the area between New Orleans, Louisiana, and Biloxi, Mississippi within 30 hours. Unexpectedly, a mid-to-upper-level trough of low pressure diving in from the northwest created a weakness in the easterly currents, allowing Elena to recurve and slow drastically in forward speed.〔 Roughly 24 hours after attaining hurricane intensity, the storm abruptly turned east in response to the trough.〔 Having defied initial forecasts, Hurricane Elena drifted on its new course toward the coast of northwest Florida. Forecasters now called for the trough to direct the hurricane across the Florida Peninsula and into the western Atlantic. However, the relatively weak trough moved rapidly, and instead of fully engaging Elena, its axis passed over the storm's center. Further, post-storm analysis of water vapor imagery suggested that the hurricane split the trough into two distinct segments.〔 Extrapolation from the storm's eastward progress yielded a projected landfall location near Levy County.〔 However, after the passage of the upper-level system early on August 31, steering currents slackened, and Elena became nearly stationary in the extreme northeastern Gulf of Mexico. At its closest, the center of the storm was around from Cedar Key, Florida,〔〔 with maximum sustained winds estimated at 105 mph (170 km/h). Elena's intensity remained consistent, and the cyclone was able to continue strengthening as soon as movement resumed. Early on September 1, Elena reached Category 3 major hurricane status.〔 An area of high pressure soon began to build over the eastern United States, causing Elena to slowly retrograde westward.〔 For much of September 1, the center of the hurricane was within range of the WSR-57 radar station in Apalachicola, Florida, enabling extensive study of small features within the eye and surrounding eyewall. During that period of observation, the previously unobstructed eye became cloud-filled. The hurricane accelerated on a trajectory toward the central U.S. Gulf Coast, sliding south of the Florida Panhandle. During the afternoon of September 1, the hurricane attained its peak intensity, with winds of 125 mph (205 km/h) as confirmed by reconnaissance aircraft.〔 On the morning of September 2, Elena approached coastal Mississippi from the east-southeast, still at major hurricane status. It came ashore close to Biloxi,〔 which was coincidentally within the hurricane's first forecast destination range before its extended detour.〔 Once inland, the hurricane immediately deteriorated, weakening to a tropical storm just hours after landfall,〔 and its center rapidly filled.〔 The system curved northwestward over Mississippi and Louisiana, and despite weakening, it continued to ignite thunderstorm activity which spawned heavy rains. Elena persisted for several days before degenerating into a remnant area of low pressure on September 4. Its associated cloud structure became distorted on September 5, and dissipated over Kentucky that same night.〔 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 Elena」の詳細全文を読む スポンサード リンク
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