The USA's infamous "Tornado Alley" may be shifting to the east.

Over the past four decades, researchers in a new study found that tornadoes have increased over a large swath of the Midwest and Southeast, including what has been referred to as "Dixie Alley."

At the same time, they've decreased in the central and southern Plains, the region traditionally known as Tornado Alley that includes large parts of Oklahoma and Texas.

“Regions in the Southeast and Midwest are closing the gap when it comes to the number of tornado reports,” said Northern Illinois University meteorologist Victor Gensini, who led the study.

Although Tornado Alley still remains the top U.S. area for tornadoes, areas to the east are catching up, based on data from 1979 to 2017. That includes portions of Mississippi, Alabama, Arkansas, Missouri, Illinois, Indiana, Tennessee and Kentucky.

“It’s not that Texas and Oklahoma do not get tornadoes,” Gensini said. “They’re still the No. 1 location in terms of tornado frequency, but the trend in many locations is down over the past 40 years.”

This new research is key for pinpointing future tornado damage. "Severe thunderstorms accompanied by tornadoes, hail, and damaging winds cause an average of $5.4 billion of damage each year across the United States, and 10-billion-dollar events are no longer uncommon," the study said.

"Economic losses associated with tornadoes will continue to increase in future years," the study also warned, adding that "the combination of an increase in risk and exposure could lead to a threefold increase in tornado disaster potential."

Overall, about 1,200 tornadoes hit the nation every year, the National Severe Storms Laboratory said. NSSL researcher and tornado expert Harold Brooks co-wrote the study.

Tornadoes in the Southeast also tend to be deadlier than those in the Plains because of several factors such as longer, larger tornado paths, expanding population, more mobile homes and more nighttime tornadoes.

On average, about 40 people die each year in the nine states that make up the southeastern U.S. Alabama tallies the highest death toll annually with an average of 14, according to data from the Storm Prediction Center.

The Mid-South, an area with Memphis at its center, is a particular worry, because it "has the greatest potential for increased tornado disasters by the end of the century," the study said.

An average of 10 people die from twisters each year combined in Texas, Oklahoma and Kansas, three states that make up most of Tornado Alley. Overall, more than 70 Americans nationwide are killed each year by tornadoes, based on data from 1985 to 2014.

Study researchers also weren't sure whether the eastward shift in tornado reports could be the result of natural or human-induced climate change.

The study was published Wednesday in the Nature partner journal Climate and Atmospheric Science.