OTTUMWA — Historic. Unprecedented. Extremely rare.
Those were the three words used by an experienced forecaster with the National Weather Service as Iowa anticipated a mid-December wind and storm event Wednesday.
The day marked the first time Iowa has had a moderate severe weather risk from the Storm Prediction Center in the month of December. Wind gusts were forecast to hit the 60 mph mark or greater across the state — with quick-moving thunderstorms threatening to push those gusts to hurricane-force.
"We don't really have any previous events to compare impacts," said NWS forecaster Mike Fowle. "We're in uncharted territory right now, to have not only a severe threat but to also have a ... non-thunderstorm wind impact — you don't see those very often, this is very rare."
The moderate risk for severe weather targeted northern Iowa. Mahaska and Marion County were under a slight risk, according to the Storm Prediction Center.
To brace for the arrival, most schools in the area announced early dismissals.
The Iowa Department of Transportation said the mile-long bridge that crosses Saylorville Lake near Polk City closed at noon Wednesday. The other mile-long bridge, which crosses Lake Red Rock near Knoxville, may also close today the department said. The department restricted travel for semis hauling overweight and oversized loads on Wednesday.
A high wind warning went into effect at noon Wednesday for Wapello County and 97 other Iowa counties. It's the first time Mahaska County has been under such a warning since 2019, and the fifth time in the last decade.
Additionally, the weather service issued a tornado watch for much of central Iowa, including Mahaska and Marion counties, for Wednesday.
As storms developed and travel in a line from west to east, they could move upwards of 80 mph — traversing the average-sized county in a matter of minutes.
"Very fast storm motion, some of the stronger I've seen in my 20 years at the weather service," Fowle said. "Faster than the derecho that we saw last August."
Northern and north-central Iowa were the predominant targets for severe weather, including tornadoes and even greater winds.