6 April 2012

There Really Is A Tornado Alley- Three Actually

Posted by Dan Satterfield

The Tuscaloosa AL Tornado on radar. New research shows that the southeast gets more deadly tornadoes than the traditional tornado alley in the Plains.

Any meteorologist gets the same question over and over: Where exactly is tornado alley?? The answer (until now) has been that there is no scientifically defined alley, but that the Great Plains from Kansas to Texas is the best answer.

Enter Michael Frates at the University of Akron. He decided it was high time to delineate the tornado alley’s of America and he did it based on historical data beginning in 1950. Frates finished up his Masters in Geography on this project, and did a great piece of overdue science in the process!

The answer is surprising as well. There are three main alleys and the most long track large tornadoes occur not in the Plains, but instead is the “Dixie Alley” in the Southeast U.S. There are many factors affecting the death toll in tornadoes, and the Southeast has lots of mobile homes (and is a historically poor part of the country), but Frates just looked at EF 3 to EF 5 tracks and image he produced below shows well where the higher risk of deadly tornadoes lies.

From Michael Frates at the Univ. of Akron. Click image for larger version or you can get a pdf of this poster at http://www.uakron.edu/dotAsset/1085452.pdf

A press release from the Univ. of Akron states:

Frates examined the distribution of tornadoes with tracks greater than 20 miles, which occurred between 1950 and 2006 over the geographic area incorporating all four regions. Frates reviewed this entire area as a grid of 3,068 cells, each representing 1,082 square miles. By studying these area units of equivalent dimension, Frates was able to study the area as a whole divided into equal parts β€” not as individual regions of varying size marked by traditional boundaries such as county and state lines β€” and ultimately, present these breakthrough findings.

Something Mike Frates did not cover in his research: Virtually every meteorologist I know grew up in one of those “alleys”. I’m from the brown rectangle in Oklahoma πŸ˜‰