On average, 1,200 tornadoes hit the US each year, according to the Storm Prediction Center, and while twisters can happen at any time, in any state, the prevailing wisdom has held that most of the large twisters occur in Tornado Alley, an expansive area designated by meteorologists in the mid-20th century. That definition may be changing.
The term was coined in 1952 when two meteorologists studied severe weather in parts of Texas and Oklahoma. The research paper, titled "Tornado Alley," was published by two U.S. Air Force meteorologists -- Major Ernest J. Fawbush and Captain Robert C. Miller, who created the first tornado forecast in 1948.
Since then, the term has stuck around to describe an area that encompasses parts of Texas, Oklahoma, Kansas, Nebraska & South Dakota, where it was believed tornadoes are the most frequent.
With powerful tornadoes decimating areas in the Midwest and the Southeast, there now may be a reason to believe that Tornado Alley has shifted east.
"When you look at the trends in where tornadoes have occurred in recent years, it's very clear that there have been more tornadoes farther south and farther east away from what people have typically known as the Tornado Alley across the Plains," AccuWeather Chief Meteorologist Jonathan Porter explained.