Storms to bring ‘torrential rainfall,’ potential flooding, tornadoes to Chicago area Wednesday

More tornadoes and flooding are possible with two storm fronts that are expected to hit the Chicago area Wednesday, forecasters said.

The first, less severe round, is expected to hit between 7 and 11 a.m., bringing mostly showers and chances of thunderstorms and localized damaging winds, according to the National Weather Service.

The second round, expected between 3 and 10 p.m., has “the better chance for severe weather,” NWS meteorologist David King said. The South Side of the city and southern Cook County appear to be at a higher risk for more severe weather.

The tornadic risk depends on a warm front that is surging north from central Illinois, King said. There is uncertainty on how far north it will reach, but it is possible it could reach past Interstate 80.

A beach hazard statement remains in effect through Thursday morning as waves could reach four to six feet tall, and life-threatening swimming conditions, according to the weather service.

“Regardless of where that warm front sets up [Wednesday], the morning and afternoon rounds — these are going to be very efficient rain makers, so we can expect torrential rainfall” and rain rates that exceed two inches per hour, King said.

That rainfall, on the heels of the heavy rainfall and storms that struck Chicago last week, could mean a high risk of flash flooding, especially in the city and areas that are more prone to flooding, such as viaducts.

King said that Tuesday, before the severe weather hits, is the best time to prepare for any flooding, damage or loss of power.

“Double check that you have batteries, that you have multiple ways to receive warnings, that you know where to go or what to do if there is a severe thunderstorm warning, a tornado warning, a flash flood warning,” King said. “What do you do and how do you stay safe?”

The forecast for Thursday, Friday and Saturday is sunny skies and temperature in the 70s.