CHICAGO — The National Storm Prediction Center has the Chicago area under an Enhanced Risk of Severe thunderstorms (see tan-shaded area on map above with a 30 percent chance of severe thunderstorms within 25 miles of a given location) mid to late morning into the early afternoon and then again later this afternoon into this Monday evening. The greatest threat of severe storms will be in eastern Iowa, much of Wisconsin and Lower Michigan, the northern portions of Illinois and Indiana.
A mesoscale convective system (concentrated cluster of fast-moving severe thunderstorms) is forecast to move quickly east through southern Minnesota and northern Iowa across southern Wisconsin and northern Illinois later this morning. Extreme wind gusts to 100 miles per hour could be associated with the strongest storms in the cluster.
Warm very moist and unstable air will ride strengthening southerly flow into our area today with a strong jet stream aloft just to our north. An upper air-impulse will trigger the mesoscale convective system this morning and a cold front approaching and moving through our area from the northwest will trigger another round of severe thunderstorms that look to hit our Chicago area late this afternoon into the evening hours today.
Supercell thunderstorms will give a threat of damaging winds, large hail and even the threat of tornadoes – with the better chance of tornadoes associated with the late afternoon/evening period.
Be aware of the explosive nature of the atmospheric conditions today and monitor latest statements/warnings radar images on this page along with simply checking fast-changing sky conditions.