Updated 4:30PM CDT…
The National Storm Prediction Center has upgraded the northern portion of the Chicago area into a Slight Risk for severe storms tonight (yellow-shaded area on the headlined map) with a Marginal Risk elsewhere. The main threat will be damaging winds with the strongest storms expected a couple or three hours on either side of midnight. Below are thunderstorm probability maps for the period 7PM to 11PM and 11PM to 7AM – most of the Chicago area is in the 40 to 70% probability of storms within 12 miles of a given location on each map.
Probability of thunderstorms 7PM to 11PM CDT…
Probability of thunderstorms 11PM this Wednesday evening until 7AM CDT Thursday morning…
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A line of thunderstorms will accompany a cold front as it moves east through our area this Wednesday evening with a few severe storms possible. The “window” for the greatest chance of storms here looks like it will be between 8PM to 1 or 2AM with storms across the city around midnight.
The timing of the front/thunderstorms arriving here this evening/overnight after the peak-heating hours diminishes the severe thunderstorm threat in our area, while areas to our north and west will be more prone to severe storms during the afternoon/early evening. The National Storm Prediction Center has the Chicago area under a Marginal Risk for severe storms with a good portion of Wisconsin into northeast Iowa under a Slight to Enhanced Risk (see headlined map).
The cold front/line of storms should be well south and east of our area by early Thursday.
