3 Things To Know:
- Isolated thunderstorms may develop this evening, primarily near the Wisconsin/Illinois border.
- A more widespread chance of rain and storms is expected overnight into Sunday morning.
- Next week will bring multiple rounds of showers and storms, with some potentially severe, especially Monday.
Overnight / Sunday Forecast
As we move into the evening, Southeast Wisconsin could see isolated thunderstorms, particularly near the Wisconsin/Illinois border. Confidence in storm formation remains low, but the HRRR model shows potential development as storms move southeastward. If any storms do materialize, they could bring gusty winds and possibly hail up to one inch in diameter.
Most of the rain may hold off until later tonight, especially as warm air lifts into the region. A Severe Thunderstorm Watch is currently in effect for areas from Iowa County through Milwaukee County.
Sunday’s Weather
Overnight, expect more widespread rain and thunderstorms as a warm front moves north through southern Wisconsin. While some storms could briefly become severe early Sunday morning, the overall threat is lower due to less favorable conditions for severe weather.
By Sunday afternoon, a low-pressure system will approach from the central Plains, which may increase the chances for severe storms, particularly in southwestern Wisconsin. However, timing and storm placement remain uncertain. Expect highs to range from the low to mid-70s near Lake Michigan to the low to mid-80s inland.
Looking Ahead
Next week appears to be quite active with multiple rounds of showers and thunderstorms expected through Tuesday. Confidence is higher that storms could be severe, particularly on Monday, as unstable conditions and moisture levels will support stronger storm development.
As noted in the forecast, “Conditions will trend quieter and cooler in the wake of the departed cold front Wednesday through Thursday.
” Keep an eye on the forecast for changes as we move through the week.
For updated forecasts where you live check out our Forecasts Page.
Source: NWS MKX Area Forecast Discussion, issued 2026-05-16T11:45:00+00:00.
