29. Warm front moving north this afternoon, lake breeze keeping the south shore cooler.
This Wunderground.comimage (to the right) shows surface boundaries this afternoon at 17:02. Regional radar is included in the map, showing several batches of storms from southern Minnesota down through eastern Colorado.
The main low pressure (1002 mb = 29.59 "Hg) was sitting back in the western Dakotas with the warm front stretching east through the Great Lakes. South of this front are the areas that may see the strongest storms tonight.
A lake-breeze has formed north of the warm front.
East winds kicked in this afternoon, bringing temperatures at my house from the mid-60s down to the upper 50s. Superior is even cooler at 48 degrees, while Duluth's harbor is at 45.
Meanwhile, south of the warm front, temperatures have managed to soar into the upper 70s with 81 degrees reported at La Crosse at 16:21. This map (to the left) is from Weatherforyou.com.