As winter changes to spring, meteorologists switch focus from winter storms to severe weather. Ramping up first in the Deep South in March, tornado season reaches its peak in ‘Tornado Alley’ in May and June.
But where the bulk of these tornadoes form seems to be shifting east. Tornado Alley still sees greater numbers of tornadoes each year, but there is a noticeable downward trend. However, there is an equally noticeable upward trend across a wide swath from Illinois to Louisiana, with tornado outbreaks becoming more common. The December 2021 “Quad State Tornado” cut a path more than 200 miles east of the heart of Tornado Alley.
This new Tornado Alley is much larger. Should we be worried?
What is Tornado Alley?
Traditionally, the term tornado alley refers to portions of the Great Plains in the central United States, an area roughly from South Dakota southward to north-central Texas. Tornadoes are most frequent in this area and have an increased chance of being more destructive.
What states are in Tornado Alley?
The traditional definition of Tornado Alley includes the states of Texas, Oklahoma, Kansas, Nebraska, and South Dakota. However, tornadoes are becoming increasingly frequent in the states east of this area and into North Dakota and the Canadian Prairies.
Where did the term ‘Tornado Alley’ come from?
While meteorologists quickly learned of Tornado Alley’s severe weather, the term was first used in 1952. U.S. Air Force meteorologists Major Ernest J. Fawbush and Captain Robert C. Miller studied severe weather in Texas and Oklahoma, and their paper was titled Tornado Alley.
Can tornadoes occur anywhere in the U.S.?
Yes. If you live anywhere east of the Rockies, chances are a tornado has passed somewhat close to your location at some point. Many meteorologists hate the term because it suggests tornadoes don’t happen anywhere else. That’s not true, and there are also areas of the Great Lakes and the southeastern United States where tornado risk is high.
Is Tornado Alley shifting east?
Research suggests that it is. A 2018 study found that tornado frequency generally decreased over the past four decades across Tornado Alley while increasing just to the east across the Lower Great Lakes and into the Deep South. The map from the study shows this (note the hashed areas).
People used to worry about a tornado in downtown Dallas; these studies suggest downtown Memphis and Nashville are more at risk. Recent events confirm this: Nashville saw a tornado rip through the city in March 2020, and Memphis is no stranger to tornadic activity either.
Some meteorologists call this region “Dixie Alley,” a nod to the increasing number of tornadoes in the South.
Is climate change to blame?
Nationwide doppler radar coverage gives meteorologists a powerful tool for detecting tornadoes, even when there is no “ground truth” to verify. This may be responsible for part of the increase in tornadoes annually. Also, while not urbanized by any means, Dixie Alley is far more populated, so tornadoes are easier to detect.
But the changes are too significant to pin on this alone, so some of these shifts are likely due to climate change. But is it natural or man-made climate change at work?
One school of thought suggests that the uptick is part of an overall increase in severe weather across the U.S. due to climate change. Climate models have been forecasting this for years.
However, another notes that the variability may stem from bigger cycles, such as differences in Pacific sea surface temperatures. This could also be shifting Tornado Alley, and we don’t have enough data to see the cycle.
The bottom line
No matter the reason, the data suggests that anyone east of Tornado Alley is at increased risk of tornadic activity. This means it is more important than ever to stay “weather aware.”
Our recommendation? Invest in a weather radio. Our favorite is the Midland – WR120B/WR120EZ – NOAA Emergency Weather Alert Radio. This weather radio can receive weather alerts directly from the National Weather Service and SAME technology, which allows the weather radio to display the type of warning even after the broadcast message ends.
That’s the easiest way to keep yourself safe and is far more dependable than the often incorrect weather app.