Tornado Alley's Activity Peaks a Week Earlier Than it Did 60 Years Ago: Warmer Weather to Blame?

It turns out that tornadoes are occurring earlier and earlier in Tornado Alley. Scientists have found that tornado activity in the central and southern Great Plains is at its peak about two weeks earlier than half a century ago.

Scientists examined tornado records from Nebraska, Kansas, Oklahoma and northern Texas. This region is dubbed as "Tornado Alley" and is known for its violent storms. Peak activity in this area usually occurs from very early May to early July. Yet researchers found that over the past six decades, it's moved an average of seven days earlier.

"If we take Nebraska out [of the data], it is nearly a two-week shift earlier," said John Long, lead author of the new study, in a news release.

Currently, the researchers haven't been able to attribute the shift in tornado activity in the region to any single cause. However, the earlier tornado activity is in-line with what could be expected in a warmer climate.

Because tornado strengths vary so widely, it's important to understand when peak tornado activity is likely to occur so that local residents can prepare. While F1 tornadoes, the weakest ones, have winds between 73 and 112 mph, F5 tornadoes, the strongest ones, have winds that can scream up to 318 mph.

"From a public safety perspective, if this trend (of an earlier tornado season) is indeed occurring, then people need to begin preparing for severe weather earlier in the year," said Greg Carbin, the warning coordination meteorologist of the Storm Prediction Center, who was not involved in the new study. He also has a possible explanation for the findings. "If winters are not as cold, or if spring times are warmer, the location of the jet stream is most likely displaced north of where it has been in the past," Carbin said. This, in turn, would cause tornado activity to shift earlier in the year.

The findings reveal a bit more about the weather patterns seen in this region, and could allow residents to better prepare for tornado outbreaks in the future.

The findings are published in the journal Geophysical Research Letters.