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The 2007 Groundhog Day tornado outbreak〔 was a localized but devastating tornado event that took place in central Florida early on February 2, 2007. Early morning temperatures had risen well above average for the season; combined with increased moisture and a powerful jet stream, this created enough instability and wind shear for thunderstorms to rotate and spawn tornadoes. Due to the conditions, a long-tracked supercell formed and produced three tornadoes over one hour and seventeen minutes. The supercell resulted in a 70-mile (110-kilometer) trail of damage. Twenty-one people were killed and 76 others were injured in the outbreak. The first tornado damaged 1,145 homes and destroyed 200 others in Sumter County before hitting the Lady Lake area where it killed eight people, damaged 180 homes and destroyed 101 homes in Lake County where it killed 21 people. The second tornado killed 13 people in the Lake Mack area and damaged and destroyed over 500 homes during its existence. The final tornado damaged roofs, car ports and garage doors along its path through New Smyrna Beach. The outbreak was the second-deadliest on record for Florida, with damages of $218 million. ==Synopsis== In east central Florida, a warm sector, a region of warm surface air between a cold front and a warm front,〔(【引用サイトリンク】 publisher =National Weather Service ) 〕 was positioned ahead of a progressing cold front. Large scale lift was supported by a very strong jet stream aloft, with strong vertical shear evident, conducive for rotating thunderstorms and tornadoes. Instability increased overnight with temperatures and dew points increasing through the pre-dawn hours.〔 For example, northwest of Orlando, temperatures were still at , which was about 3 degrees warmer than the average high for the day and 14 degrees warmer than the average low.〔 The conditions helped to form a long-tracked supercell thunderstorm that traveled from Sumter County to the coastal waters of Volusia County during the early morning hours of February 2, 2007, producing three tornadoes along its track.〔(【引用サイトリンク】 publisher =National Weather Service Melbourne Weather Forecast Office ) 〕 At 3:06 am EST (0806 UTC), the National Weather Service (NWS) issued a tornado warning for northern Lake County until 4:00 am EST (0900 UTC). At 3:10 am EST (0810 UTC), the first tornado touched down near The Villages and traveled at into Lake County.〔(【引用サイトリンク】 publisher =National Climatic Data Center ) 〕 Five minutes after the tornado touched down, a severe weather update bulletin was issued by the NWS stating that there was a high likelihood of an extremely dangerous tornado and people in the path were in a life-threatening situation. The tornado received an EF3 rating on the Enhanced Fujita Scale and had a track length of .〔 Initially, the tornado was thought to have still been on the ground and a third bulletin was released at 3:34 am EST (0834 UTC). At this time, Doppler radar indicated that a tornado was forming or was on the ground roughly north of Umatilla. The mesocyclone that produced the first tornado restrengthened and formed another tornado near Paisley at 3:37 am EST (0837 UTC) in Lake County.〔 A second tornado warning was issued at 3:52 am EST (0852 UTC) for Volusia County as the tornado was tracking toward the area. It went east northeast toward the Lake Mack area, exceeding .〔(【引用サイトリンク】 publisher =National Climatic Data Center )〕 The tornado received an EF3 rating on the Enhanced Fujita Scale and traveled a total of .〔 A third tornado warning was issued in Volusia County at 4:13 am EST (0913 UTC), nearly ten minutes before the third tornado touched down. The supercell produced its last tornado east of Interstate 95 at 4:22 am EST (0922 UTC) and dissipated five minutes later at the Intracoastal Waterway, from where it touched down.〔(【引用サイトリンク】 publisher =National Climate Data Center )〕 The tornado had a maximum width of around the time it reached peak intensity.〔(【引用サイトリンク】 publisher =National Climatic Data Center ) 〕 The tornado was rated EF1 on the Enhanced Fujita Scale and traveled for .〔 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「2007 Groundhog Day tornado outbreak」の詳細全文を読む スポンサード リンク
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