Tornado in Pekin, Ind., on Friday, March 2, 2012, by Emily Naugle Gibson. By Meghan Evans, Meteorologist
Mar 28, 2012; 4:16 PM ET
There have been more tornadoes so far this year compared to the same time period during the extremely active 2011.According to graphs provided by the Storm Prediction Center, there were 379 preliminary tornado reports through March 25 in 2012. Compared to past years, this is a very busy start to the severe weather and tornado season.
There was a total of 154 tornadoes from January through March of 2011. The three-year average number of tornadoes in January, February and March add up to 124.
The only other recent year where the number of tornadoes surpassed this year was in 2008, when 491 tornadoes touched down through March 25.
The March 2, 2012, Tornado Outbreak was the biggest of 2012 with 132 tornado reports and at least 61 confirmed tornadoes so far. At least 39 people were killed by the dangerous tornadoes that leveled entire towns like Marysville and Henryville, Ind.
SEE ALSO:
Photos of Horrific Damage From March 2, 2012, Tornado Outbreak
Science Behind the March 2, 2012, Tornado Outbreak
Rare March tornadoes have touched down as far north as southeastern Michigan this year.
Why Has 2012 Started Out So Volatile?
The above-normal warmth of the Gulf of Mexico is a big factor in the large number of tornadoes so early this year.
"Water temperatures in the Gulf of Mexico did not cool off this winter without cold air masses reaching the Deep South," AccuWeather.com Expert Senior Meteorologist Dan Kottlowski said.
The warmer-than-normal temperatures in the Gulf of Mexico mean any time the flow switches out of the south, warm and humid air is drawn into the U.S.
Warm, moist air are key ingredients for thunderstorms that are strong enough to spawn tornadoes.
"Ground temperatures are also warmer than normal... This is one of very few years of recent, where the ground was not frozen across the Ohio Valley," Kottlowski explained. When the ground is cold or frozen it creates an inversion, which means temperatures rise with rising altitude. An inversion creates a stable atmosphere and can prevent thunderstorms from forming or allow only higher-based thunderstorms to develop.
"Lower-based thunderstorms create much more opportunity for tornadoes," Kottlowski added.
Will 2012 Remain Active with Tornadoes?
The active severe weather has quieted down a bit over the past couple of weeks, but more active severe weather is anticipated. In fact, another peak in severe weather is anticipated later this spring.
"Severe weather will get more active by the middle of April," according to Jack Boston, AccuWeather.com expert senior meteorologist and long-range forecaster.
"The pattern will get more progressive," Boston said, meaning more storms will cross the country.
"April is one of the more volatile months," Kottlowski weighed in. However, he cautioned that "unless we see another cold air mass come down from the north, severe weather could occur at any time this season."
There were 379 preliminary tornadoes reports from Jan. 1-March 25, 2012. That is well above the average number of tornadoes from 2005-2011 during the same time period. Graph from the Storm Prediction Center.
Plot of the annual running total of U.S. tornadoes. The only year plotted in which the number of tornadoes surpassed the number Jan. 1-March 25, 2012, during the same time period, was in 2008 when there was 491 tornadoes. Graph from the Storm Prediction Center.
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