Severe storms could hit the Chicago area this Sunday evening into the overnight hours. Winds are expected to pick up out of the southwest gusting in excess of 30 mph later this afternoon and early evening, combining with temperatures warming back into the 80s along with dew-points in the upper 60s to around 70-degrees, destabilizing the low levels of the atmosphere over northern Illinois and southern Wisconsin ahead of a cold front approaching from the northwest.
There is a good chance a band of strong to severe thunderstorms will develop along and ahead of the cold front, moving into and across our area later this evening into the early overnight. The latest projection by the National Storm Prediction Center has northern Illinois and southern Wisconsin as well as NW Indiana and western Lower Michigan in a Slight Risk for severe thunderstorms (yellow-shaded area on the headlined map).
Breaking down this outlook further…there is a 15 % chance of damaging winds and large hail within 25 miles of a given location in the Slight Risk area. There is a 5 percent chance of a tornado within 25 miles of a given point generally along and north of the Interstate-80 corridor (see brown-shaded area on map below) and 2 percent elsewhere.