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The February–March 2007 tornado outbreak sequence was a deadly tornado outbreak across the southern United States that began in Kansas on February 28, 2007. The severe weather spread eastward on March 1 and left a deadly mark across the southern US, particularly in Alabama and Georgia. Twenty deaths were reported; one in Missouri, nine in Georgia, and 10 in Alabama. Scattered severe weather was also reported in North Carolina on March 2, producing the final tornado of the outbreak before the storms moved offshore into the Atlantic Ocean. In the end, there were 56 tornadoes confirmed during the outbreak, including three EF3 tornadoes reported across three states, as well as three EF4 tornadoes; two in Alabama and one in Kansas, the first such tornadoes since the introduction of the Enhanced Fujita Scale. Total damages were estimated at over $580 million from tornadoes alone, making it the fourth costliest tornado outbreak in US history (the figure not including damage from other thunderstorm impacts including hail and straight-line winds).〔 Insured losses in the state of Georgia topped $210 million, making this outbreak the costliest in that state's history.〔(【引用サイトリンク】title=Ga.: Losses from March 1 Storms Top $210 Million )〕 Enterprise, Alabama, which was hit the hardest, sustained damages in excess of $307 million.〔(【引用サイトリンク】title=AL recovery shows real 'Enterprise' )〕 == Meteorological synopsis == The tornado outbreak was related to a large low-pressure system across the central United States that intensified on February 28 while over Kansas, and a cold front moved across the region, providing the lift needed to allow the storms to develop. In addition, a surge of very moist air from the Gulf of Mexico and warm temperatures across the south side of the storm helped feed the storms. Temperatures were in the 70s °F (low 20s °C) in some areas to the south, while the mercury was below freezing on the north side. The dewpoints were in the 60 °F (16 °C) range as far north as southeastern Kansas, which provided extra fuel.〔(【引用サイトリンク】title=Feb 28, 2007 1630 UTC Day 1 Convective Outlook )〕 A moderate risk of severe storms was issued by the Storm Prediction Center for February 28 across parts of the central Plains. The first tornadoes developed early in the evening of February 28 in Kansas as the dry line pushed eastward and was lifted by the cold front.〔(【引用サイトリンク】title=Feb 28, 2007 2000 UTC Day 1 Convective Outlook )〕 In total, 12 tornadoes formed that evening across Kansas and Missouri, of which 11 were weak. However, one of the tornadoes was an EF4, the first such tornado recorded and the first violent tornado since September 22, 2006. No one was injured that evening. Farther south, expected activity in Oklahoma and Arkansas did not take place as the atmospheric cap held up.〔(【引用サイトリンク】title=Mar 1, 2007 0100 UTC Day 1 Convective Outlook )〕 A high risk of severe storms—the first such issuance since April 7, 2006—was issued for a large part of the Deep South for March 1 as the cold front moved eastward.〔(【引用サイトリンク】title=Mar 1, 2007 0600 UTC Day 1 Convective Outlook )〕 The activity began almost immediately, with several isolated tornadoes taking place that morning across the Mississippi Valley, with one of them leading to the first fatality of the outbreak. Isolated tornadoes were also reported as far north as Illinois, near the center of the low. However, the most intense activity began around noon and continued throughout the afternoon and evening, with southern Alabama and southern Georgia hit the hardest. Nearly continuous supercells formed north of the Gulf of Mexico and produced many tornadoes, some of which hit large population centers with devastating effects. 20 people were killed by those tornadoes.〔(【引用サイトリンク】title=Mar 1, 2007 2000 UTC Day 1 Convective Outlook )〕 The squall line finally overtook the supercells just after midnight on March 2, after putting down 37 tornadoes that day. As the squall line overtook the cells, a few tornadoes — all EF0 — took place overnight in Florida and extreme southern Georgia within the squall line, before the severe weather emerged in the Atlantic Ocean that morning.〔(【引用サイトリンク】title=Mar 2, 2007 0100 UTC Day 1 Convective Outlook )〕 The final tornado was a landfalling waterspout in the Outer Banks of North Carolina late that morning.〔(【引用サイトリンク】title=Event Record Details )〕 In addition to the tornadoes, widespread straight-line wind damage from microbursts were also reported, along with scattered large hail, the largest of which were the size of baseballs.〔(【引用サイトリンク】title=20070301's Storm Reports )〕 On the other side of the low pressure area, a significant blizzard occurred over the northern Great Plains and Upper Midwest, including parts of Minnesota, Manitoba, Saskatchewan, Wisconsin, Iowa and Nebraska, where several snowfalls in excess of 8 to 18 inches (20–45 cm) were reported, as well as snow of between 6 and 11 inches (15–28 cm) across portions of Ontario and Quebec. Freezing rain was reported across New England, the lower Great Lakes in Ontario, Michigan, and in the Chicago area. 19 people were killed by the storm, including two in Manitoba, two in Ontario, one in Massachusetts, four in North Dakota, one in Minnesota, three in Michigan, five in Wisconsin and one in Nebraska. The University of Minnesota in the Twin Cities was closed for the first time since 1991 and the roof of a supermarket in Wisconsin collapsed. Minnesota Governor Tim Pawlenty called in the National Guard while governors Chet Culver (Iowa) and Michael Rounds (South Dakota) issued disaster declarations〔(【引用サイトリンク】title=Blizzard Hits Region )〕 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「February–March 2007 tornado outbreak sequence」の詳細全文を読む スポンサード リンク
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