Severe weather season off to violent start

Severe weather season is off to a near record-breaking start across the country - with nearly 400 tornado reports so far this year.

That is the most number of tornadoes this early in five years, and more than double the normal number of sightings. A confirmed tornado touched down in central Massachusetts in February, a first for the state while there was still snow on the ground. On March 6, a tornado touched down in Minnesota, marking that states earliest tornado ever in a year.

The United States normally averages about 1,200 tornadoes a year, more than any other country on earth. Ohio has already been struck by eight tornadoes since the beginning of 2017 with seven of those touchdowns occurring in southwestern Ohio.

More severe weather, including tornadoes, is expected through at least the first half of this week before unseasonably cool air arrives that should quiet the storms down briefly. An active jet stream and unusually balmy weather are to blame for the burst of deadly tornado activity, the Storm Prediction Center said. Strong winds have pushed storms into the warm, humid air that’s blanketed the eastern half of the nation, creating conditions ripe for severe storms. Parts of Ohio could be back in the severe weather threat zone Wednesday before a blast of chilly air ends any thunderstorm threat by Thursday.

The uptick in severe weather this season is due to a unusually mild winter and early arrival of spring moisture and warmth. Weather conditions across the Southern Plains and southeastern U.S. were more typical of April since January fueling strong storms to start the New Year. February in Ohio was tied for the warmest on record which fueled the first tornadoes of the season.

Tornado “outbreaks,” or storm systems that spin out multiple funnels in a limited time and area, are becoming more frequent in the U.S., according to study recently published in the journal Science. Since 1980, losses due to severe thunderstorm events in the U.S., which includes tornadoes, hail and straight-line winds, have increased dramatically largely due to socioeconomic effects.

Despite the increase in tornado outbreaks in recent years, it is unclear if climate change is the reason. While it is believed our changing climate is the cause of increased global temperatures, there are competing factors on how increased temperatures would impact very small-scale events like tornadoes. As the air gets warmer, it can hold more moisture. This increase in moisture would increase the threat for tornadoes. However, an overly-moisture laden atmosphere can decrease the amount of wind-shear which creates the “spin” for tornadoes, which would tend to decrease the tornado threat. The result in the future may be more large-scale storm systems that can produce tornadoes, but fewer tornadoes within these storm systems. The other result could be while there could be fewer number of tornadoes that occur with a warming climate, the tornadoes that do occur could be stronger and cause more damage.

Here in Ohio, we normally average 16 tornadoes a year. We’ve already had half of that, and our severe weather season is just getting underway. So be ready for anything this year.

Eric Elwell is WHIO StormCenter 7 Chief Meteorologist. Contact him at or follow him on Facebook and Twitter.

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