BLOOMINGTON — A storm system developing out west could drop several inches of snow across the Plains, but in Central Illinois the biggest threat, starting Wednesday, will be damaging winds.
This storm is part of the region’s second “bomb cyclone” within a month, which results from a rapid pressure drop and brings in a potent, intense storm system.
The most severe aspects of the storm system may miss Central Illinois, but Kirk Huettl, a meteorologist at the National Weather Service in Lincoln, said he’s expected strong, damaging winds that could send loose patio furniture and garbage cans rolling.
Wind speeds will begin to increase Wednesday as the storm moves into Central Illinois. Gusts will range from 20 mph to 30 mph, according to the weather service.
By Thursday afternoon, the wind gusts will peak at about 41 mph in Bloomington-Normal.
East of Bloomington and Decatur, a slight risk of severe storms is forecast for Thursday, which could mean isolated tornadoes, 1-inch hail and deadly lightning, according to the weather service.
From Bloomington to Peoria and from Decatur to Springfield, there will be a marginal storm risk, which poses less of a threat.
After the last few warm and sunny spring days, the temperatures will drop below normal for Central Illinois as the storm system moves through.
The high temperature will reach the low 70s on Thursday before dropping to 40 Thursday night. Friday’s high will be 50, about 10 degrees cooler than the average temperature for this time of year.
Friday night will bring the lowest temperature at 34 degrees, which could leave some frost overnight. Through the weekend, the temperature will remain around 50.
Monday and Tuesday will be dry and temperatures will start warming up again.
As rare as inland bomb cyclones are, the resulting storms fit into the Central Illinois severe weather season that spans April through June, Huettl said.
A bomb cyclone often is over or near an ocean because it requires warm moist air smacking into cold dry air, along with volatile weather from the jet stream. The central and mountain part of the country may get one of these every few winters, said Greg Carbin, forecast branch chief for the National Weather Service's Weather Prediction Center in Maryland.
But this would be the second such storm in less than a month. The March 13 storm caused massive flooding in the Midwest, a blizzard in Colorado and Wyoming and produced winds of between 96 mph and 110 mph.
This week's bomb cyclone is expected to be similar in intensity and in snowfall, meteorologists said. Heavy, wet snow will fall from the Nebraska panhandle through south central and southeastern South Dakota into western Minnesota.
Any additional rainfall in Central Illinois also could affect the flood stage of the Illinois River, which was close to 18 feet near Havana on Tuesday morning, according to the weather service.