We’ll be stepping right into summer on Thursday as a strong southwest wind and warming temperatures aloft support many locations reaching the middle to upper 80s by the afternoon.
On the radar this morning is a cluster of thunderstorms racing southeast through parts of Minnesota and southwest Wisconsin. This storm cluster is expected to remain north of the local area, but we will see a lot more cloud cover this morning until this storm complex passes to the east. This complex will lay out an outflow boundary this afternoon somewhere close to our area. At this time, it appears our atmosphere will be capped, with a warm layer aloft suppressing severe thunderstorm development until after dark. While an isolated thunderstorm is possible this afternoon, the more widespread activity will take place after 7pm this evening.
Before those storms arrive this evening, temperatures will soar well into the 80s with a gusty southwest breeze. Some humidity will make it feel a bit uncomfortable at times, too, but heat index values are expected to remain fairly close to the actual temperature.
As we go through the evening, the cap is expected to rapidly weaken and scattered thunderstorms will develop along the outflow boundary from the earlier storms. A cold front will also be moving south and that combined with a low-level jet that develops through the night will keep clusters of showers and storms going up through Friday morning. These storms will likely move over the same areas repeatedly and will cause some minor flooding in spots. Rainfall amounts will likely exceed an inch where the heaviest storms form.
Other threats from these storms will be hail up to one inch in diameter and wind gusts up to 60 MPH. Frequent lightning is also likely. An isolated tornado or two can’t be ruled out, especially earlier in the evening before storms begin to solidify into a cluster/line.
We’ll keep an eye on how ingredients come together throughout the afternoon. More updates as warranted.