Hot and humid weather will continue, with daytime temperatures warming into the 89 to 94 degree range today. These warm temperatures along with the high humidity will result in heat index readings reaching the 95 to 102 degree range during the afternoon. A Heat Advisory remains in effect until 7 pm CDT this evening. Check here for the latest details on the Heat Advisory. For tips on dealing with the heat, check out our Heat Wave Safety Rules. Remember: never leave children, pets or the elderly in a parked vehicle. The National Weather Service in Milwaukee/Sullivan did an experiment several summers ago measuring how hot the interior of a vehicle gets in a short amount of time. Here is a link to our hot car experiment.
The below image outlines where heat advisory and excessive heat warnings are currently in effect across the western Great Lakes and Upper Midwest.
The latest Heat Indices from around Wisconsin can be found in the Wisconsin Regional Weather Roundup. The Heat Index value is listed in the remarks section as HX.
A stationary weather pattern is responsible for the hot weather across southern Wisconsin and the surrounding region. High pressure located at about 10,000 feet over the nation's mid-section has remained stationary for the past several days, and is not expected to move until later today. Southwest winds north of the high and evaporation has resulted in high dew points in the 70s and resultant high humidity values and sultry conditions. Little change is anticipated until late today and the weekend.
A change in the weather pattern will arrive late today into Saturday. The frontal boundary that had been stationary across Lake Superior and the northern Plains will gradually sag southeast. The front will move through southern Wisconsin this afternoon and early evening. It will likely set off scattered thunderstorms as it passes across the region. Some of the thunderstorms will be strong to severe. Northwest winds in the wake of the front will usher less humid and cooler conditions into southern Wisconsin for the weekend. The less humid conditions will be felt as soon as Friday evening.
South central and southeast Wisconsin may experience strong to severe thunderstorms as the cold front moves through this afternoon and evening. There is a slight risk that some of the thunderstorms could become severe, producing damaging wind gusts and large hail.
Here is the deliniation of the slight risk area for today as outlined by the Storm Prediction Center:
Here are several regional radars showing the current location and movement of the thunderstorms: