CHICAGO — With a warm front slowly moving north out of central Illinois and a low-level southwesterly jet stream pouring warm moist air into northern Illinois — along with upper-air support to trigger storms — the next 24 to 48 hours look to be very wet and stormy for the Chicago area.
A Flash Flood Watch for Friday night into Saturday morning for the Chicago area counties adjacent to and north of Interstate-80 (green-shaded area on the headlined map) has been issued by the Chicago National Weather Service Forecast Office.
The National Storm Prediction Center has the area included in a belt of Severe Storm and Excessive Rainfall potential that extends from Texas northeast through Oklahoma, Missouri, Iowa, Illinois/NW Indiana into Wisconsin and Lower Michigan. See Slight Risk of Severe Storms (yellow-shaded area) and Slight to Moderate Risk of Excessive flood-producing rainfall (yellow and red-shaded areas) on the outlook maps below.
Showers and thunderstorms are likely to redevelop here later this afternoon and continue overnight into Saturday with “training” of thunderstorms producing flooding downpours (storms redeveloping and passing over the same locations).
Severe Thunderstorm outlook Friday/Friday night night:
Excessive Flood-producing rainfall outlook Friday/Friday night: