New Tornado Frequency Maps

The Storm Prediction Center released its new 30 year averaged tornado statistics from 1981 to 2010. The statistics used up until now were from 1971-2000. The map above shows average numbers of tornadoes per state. Arkansas now averages 33 tornadoes per year State wide. This number is up from 26 based on the previous 30 year average. The reason for the increase isn't likely from an actual increase in the frequency of tornadoes, but rather due to more people observing tornadoes and more verification of tornado damage in rural areas by The National Weather Service. Texas has by far the greatest number of tornadoes at 150. Of course, Texas is also much larger. The map below adjusts tornado frequency for state size by calculating average number of tornadoes per 10,000 square miles


In this case, Arkansas actually has a greater tornado frequency than Texas per square mile. Kansas has the greatest frequency per 10,000 square miles at 14. Arkansas averages 9 tornadoes per 10,000 square miles and Texas averages 5.