April 2011 is officially the record-holder for most tornadoes in one month, according to the Storm Prediction Center (SPC) in Norman, Okla.
A record-breaking 753 tornadoes touched down in April, topping the previous record of 543 that struck in May 2003, according to a new SPC report issued after meteorologists combed through storm reports to verify them and weed out any duplicates. Modern records of tornado counts began in 1950.
The deadly Dixie Alley outbreak pushed the month into infamous territory. In that outbreak, from April 25 to 28, tornadoes killed more than 300 people, adding to one of the deadliest tornado seasons in history.
Because the final count ruled out duplicate tornado reports, the total is smaller than the preliminary number of 875 tornadoes reported at the end of April.
While May 2003 was the previous overall record-holder, April 1974 was previously the most tornado-plagued April, with 267 twisters. The average for April is 116, according to the SPC.
A whopping four EF-5 tornadoes struck during April. An EF-5 rating is the highest on the tornado damage scale. Before 2011, an EF-5 tornado had not hit the United States in three years.
In Dixie Alley, the southeastern neighbor to the more famous Tornado Alley, where many of the April twisters struck, tornadoes do not need to be big to be deadly. Unlike the flat, grass-covered plains of Tornado Alley, tornadoes are hard to see in Dixie Alley. Trees and hilly terrain obscure funnel clouds, a problem made even worse by the region's high rate of nighttime tornadoes. The region is also home to many manufactured houses and mobile homes that have weak walls and poor or nonexistent foundations, making them more vulnerable to damage and destruction.
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