2009 Minnesota tornadoes
The following is a list of 2009 Minnesota tornadoes. Minnesota is a state located in the North Central United States along the northern edge of Tornado Alley, and on average receives 24 tornadoes per year. 2009 was an average year historically, with 24 confirmed tornado touchdowns. Twenty-two of the tornadoes (91%) were considered minor, rated EF0 or EF1 on the Enhanced Fujita scale. The remaining two tornadoes were rated as significant, at EF2.
The 24 tornadoes combined to cause $4.5 million in damage, and they did not cause any fatalities or injuries. The date range of the tornadoes was smaller than normal, lasting just over two months, from just June 17–August 19. The first tornado date of June 17 marked the third-latest-starting tornado season on record in Minnesota since 1950, behind only 1951 (June 19) and 1952 (June 23).
The most unusual tornado event of the year occurred on August 19. Seven tornadoes were recorded in Minnesota that day, including one that touched down in Minneapolis. What made this day unusual is that a unique atmospheric setup allowed several of the tornadoes to be spawned from rain showers where no lightning was present.
A weak area of surface low pressure moved into extreme southeast North Dakota late on the afternoon of the June 17, with a warm front stretching across southeastern Minnesota. The warm front combined with pre-existing moisture from morning rainfall which led to rapid destabilization of the atmosphere during the afternoon hours. To the east of the low pressure area, surface dew point values rose into the middle 60s °F (18 °C) with temperatures near 80 °F (27 °C), causing a very unstable air mass to develop.
Two tornadoes were reported in west-central Minnesota in Wilkin County. Other, strong thunderstorms developed later just south of the warm front near Albert Lea and moved northeast. The thunderstorms quickly became tornadic north of Albert Lea, near Geneva, where a touchdown was observed. There were several reports of funnel clouds throughout the early evening with one more official touchdown near Waseca. The storms later turned to the southeast and impacted the Austin area, causing serious damage.
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