National Weather Service issues flash flood warnings for Madison, St. Clair counties

Portions of Madison and St. Clair counties are again under a flash flood warning.

According to Lydia Jaja, a meteorologist with the National Weather Service of St. Louis, the cities most in the crosshairs are Cahokia Heights, Fairmont City, East St. Louis, Granite City and Madison. The flash flood warning is set to expire at 7:30 p.m.

“The expected rainfall rate is one to two inches per hour, but those areas could see more than that. Possibly two to three inches per hour,” Jaja said Thursday afternoon.

Following Tuesday’s record-setting rainfall, “with the urban area and everything already saturated it doesn’t take much to get flash flooding.”

On a related note, Melissa Mainhart, also a meteorologist with the NWS, on Tuesday explained the difference between a flash flood warning and a flood warning.

“A flash flood warning is for water that is moving into an area quickly. That’s more descriptive of this morning (on Tuesday),” she said. “A flood warning is for flooding that’s happened but hasn’t yet receded. The fact the water is not rising or adding to the flooding means we’re not looking at the floodwaters coming up higher. The water might be receding slowly, but it’s not moving and we’re not gaining any more water.”

Jaja offered these precautions as well.

“Of course, turn around don’t drown. If you see water over roadway don’t drive through it. Also, have your phone on in case any warning get extended. People need a way to figure that out,” she said.

St. Clair County reported making 90 flood related rescues on Tuesday.

The National Weather Service recommends keeping plugged into the forecast as it develops at www.weather.gov. Their Facebook page is www.facebook.com/NWSStLouis.

This story was originally published July 28, 2022 at 3:28 PM.