Some clouds were moving through northern Minnesota in association with a weak surface boundary. According to NWS Duluth's forecast discussion, an upper trough will absorb the surface wave and possibly bring some showers and thunder to the region in the next 24 hours.
On top of the satellite image, I have drawn in the Convective Outlooks for Day 1 and Day 2 from the SPC. Thunder is possible to the left of the pink line today, which shifts eastward tomorrow. Any scattered showers or storms that do form will only produce light amounts of precipitation.
Scattered frost last night across inland areas.
This map (to the left) is from US Hourly Weather Statistics and shows temperature contours at 6:00 CDT this morning. It doesn't fully cover the cool conditions across Wisconsin this morning, but it does indicate temperatures below 40 degrees across most of the western Great Lakes, with even some temperatures below 30 degrees in central Michigan. I put some low temperatures reported this morning into a spreadsheet (to the right). Frosty temperatures were reported all the way south to areas around La Crosse and Milwaukee.
I escaped with a low temperature of only 43.6 degrees just after midnight. I'm sure the Lake helped keep temperatures from plummeting. It can be evil by reducing daytime highs, but can be a blessing when it keeps overnight temperatures higher.
Today's sunshine and warmth.
Forecast high temperatures across the region will climb to 70 degrees, or a little above, throughout most of Wisconsin today. However, the Lake Michigan coastline will remain in the 50s and 60s with a marine influence and close proximity to a weak high pressure.