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The January 2008 tornado outbreak was an unseasonably strong tornado outbreak that began on January 7, 2008 and continued for nearly four days, with the hardest hit area being southwestern Missouri, northwestern Arkansas and the surrounding area. In addition, a strong supercell in northern Illinois and southeastern Wisconsin produced that region's first January tornadoes since 1967. More tornadoes occurred across the Mississippi Valley on January 8 and after a break in the activity on January 9, another round of severe weather took place in the Southern United States (primarily Alabama and Mississippi) on January 10. Several damaging tornadoes were reported that day, although no one was killed. In total, over the four-day period, 72 tornadoes were confirmed and four people were killed. ==Meteorological synopsis== An unseasonably warm air mass was entrenched over much of central and eastern North America with record highs for much of the region. Several record high temperatures were broken across several states and Canadian provinces from January 7 to January 9 as temperatures rose into the 70s (21–25 °C) as far north as the Ohio Valley with dewpoints in the high 50s and low 60s (14–17 °C) providing additional fuel for storm development. In addition, many areas near the Great Lakes region reached the mid to upper 60s (17–20 °C) which allowed the northern cells to form, while several areas in southern Ontario and Quebec near the Canada-US border reached near 60 °F (16 °C).〔(【引用サイトリンク】title=Ontario, CA )〕〔(【引用サイトリンク】title=Timmins Daily Press – Ontario, CA )〕 A strong low-pressure area over the central Great Lakes and its associated cold front combined with intense wind shear to provide a favorable environment for supercell development.〔(【引用サイトリンク】title=Storm Prediction Center Jan 7, 2008 1300 UTC Day 1 Convective Outlook )〕 Despite only moderate instability (which meant only a slight risk of severe weather was issued by the Storm Prediction Center, and only modest probabilities for severe weather at first〔(【引用サイトリンク】title=Storm Prediction Center Jan 7, 2008 0600 UTC Day 1 Convective Outlook )〕), supercells developed throughout the day over much of the central US and continued throughout the evening and overnight hours, continuing into the morning of January 8. The hardest-hit area was in the Ozarks, around Springfield, Missouri, where nearly continuous supercells developed throughout the evening, resulting in numerous tornado touchdowns. In addition to the tornadoes, hail larger than baseballs and damaging straight-line downburst winds as strong as 100 mph (160 km/h) were reported. At least three people were killed in Missouri as a result of the tornadoes. Two of these deaths occurred near Marshfield and there were also six injuries. Strong tornadoes also touched down further north near Chicago and Milwaukee causing extensive damage along the Wisconsin/Illinois border as well as several injuries. Strong cells and lines also formed in Michigan prompting rare tornado warnings across central parts of Lower Michigan.〔(【引用サイトリンク】title=Mt. Pleasant Morning Sun )〕 Scattered thunderstorms were reported in Northern, Central and Southern Ontario on the evening of January 7.〔(【引用サイトリンク】title=The North Bay Nugget – Ontario, CA )〕 Tornado watches extended from eastern Oklahoma to southwestern Ontario on January 7. Activity shifted across the Mid-Mississippi Valley on January 8 where tornado watches were issued across Arkansas and Tennessee and later extended across the Ohio Valley to near Columbus, Ohio and Dayton, Ohio until the early morning hours on January 9. A strong tornado in Pope County, Arkansas killed at least one person and additional tornadoes were reported just west of Memphis. During the day, most of the activity was formed into a line that extended from the Ohio Valley to Alabama although thunderstorm-related wind damage was reported as far north as upstate New York and western Pennsylvania. After a lull in activity on January 9, a separate system across the Southern United States led to more severe weather, including tornadoes, on January 10. A moderate risk of severe weather was issued by the Storm Prediction Center. Storms developed across Louisiana and Mississippi during the morning and noon periods moving into Alabama with additional storms developing as far north as central and eastern Kentucky where a tornado watch was issued stretching down towards eastern Louisiana and later into Georgia. One particular storm produced several tornado reports across Attala County and near Starkville with some structural damage. At around 2:20 pm CDT, a tornado warning was issued for Lamar County, Alabama after a report of significant structural damage was received in Caledonia, Mississippi in Lowndes County; a tornado was later spotted by the emergency management in the downtown Vernon, Alabama area. Additional tornadoes were reported from a storm that moved from southeastern Mississippi to north of Tuscaloosa later in the afternoon causing extensive damage in northeastern portion of Tuscaloosa County. More stable air farther east reduced the severe weather potential. Wintry weather including snow, sleet and freezing rain on the northern side of the storm was reported from Wisconsin to Maine on January 10–11. 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「January 2008 tornado outbreak」の詳細全文を読む スポンサード リンク
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