The storm activity, which comes unusually late in the year, seems ominous. Could it be the beginning of a trend in a region not really known for tornadoes?
One expert has found that tornadoes are shifting eastward but not, at this point, into the Northeast.
“While the trend is upward, it’s just not [statistically] significant yet,” said Victor Gensini, a meteorology professor at Northern Illinois University.
But he also said, “The take-home message for the Northeast is the Northeast is vulnerable to storms. We’ve got to basically keep an eye on it, keep monitoring it.”
Gensini and Harold Brooks, a researcher from NOAA’s National Severe Storms Laboratory in Norman, Okla., authored a study published Oct. 17 in the journal Climate and Atmospheric Science that looked at the frequency of tornadoes over the past four decades.
The researchers found tornado frequency had decreased in portions of the central and southern Great Plains, in the area many people call “Tornado Alley.”
At the same time, they found that tornado frequency had increased over a large swath of the Southeast and Midwest. The researchers identified significant increases in portions of Mississippi, Alabama, Arkansas, Missouri, Illinois, Indiana, Tennessee, and Kentucky.
“Regions in the Southeast and Midwest are closing the gap when it comes to the number of tornado reports,” Gensini said.
“It’s not that Texas and Oklahoma do not get tornadoes,” Gensini said in a statement. “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.”
The researchers looked at tornado reports from 1979 to 2017 and also examined data on tornado-conducive atmospheric conditions over the same period. Both showed the same increase — to the east.
Is climate change responsible?
“We don’t know for sure,” Gensini said. “The shift east is consistent with climate change. There have been several papers that have discussed this eastward shift.”
“It’s fair to hypothesize,” he said, but “we can’t say yes or no just yet.”