CHICAGO — The National Storm Prediction Center has included the Chicago area in a Marginal to Slight Risk of Severe thunderstorms late this Thursday morning into the afternoon. As a center of low pressure passes just to our north through southern Wisconsin, the associated cold front will approach and pass through the Chicago area from west to east – the band of strong to severe thunderstorms moving through the western portion of our area mid-to-late morning, passing over Chicago midday and eventually moving into Indiana to our east in the afternoon. The greatest risk here will be for strong damaging winds and large hail.
The closer the time of occurrence coincides with the peak-heating of the day, the more intense the thunderstorm activity will become. The western portion of the Chicago area will be in the Marginal Risk of severe storms (dark-green-shaded area on the map above projecting a 5% chance of severe storms within 25 miles of a given location) mainly later this Thursday morning/midday. From Chicago south and east into northwest Indiana there will be a Slight Risk of severe thunderstorms (yellow-shaded area on the map above calling for a 15% chance of severe thunderstorms within 25 miles of a given location) mainly midday into the afternoon hours.
As the cold front moves to our east into Indiana, the threat of severe storms will increase this afternoon over southeastern Illinois and portions of Indiana farther to our east and south.