Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
381 FXUS63 KMKX 292004 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 304 PM CDT Fri Aug 29 2025 .KEY MESSAGES... - Area of showers moving through southern WI this afternoon, with a chance of lingering showers tonight. Slight chance (~15%) for lightning. - Dry conditions with a gradual warming trend this weekend into early next week. - Next shower and thunderstorm chances (~40-60%) return to the forecast Wednesday into Thursday. && .SHORT TERM... Issued 303 PM CDT Fri Aug 29 2025 Tonight through Saturday night: The area of showers with isolated lightning that was over west central WI this morning and is now over south central WI. It is associated with warm, moist advection just above the surface. The rain should keep going through southeast WI late this afternoon, and there is a rough back edge to it. Meanwhile, a weak shortwave trough will be dropping down through WI, and it should intersect this area of showers as it crosses southeast WI this evening. If the timing works out, the shower activity should persist here into the evening hours. There have already been a couple of lightning strikes in south central WI, although few and far between. I expect that trend to continue through the evening since the instability is very low and cloud cover has been excessive. Speaking of clouds, if they linger into the overnight hours, the chance for fog will be lower. If they clear out, then we can expect areas of fog. Dense fog will be possible in areas that saw the steadier rain today, generally west of the Dells to Madison. The surface high pressure that is over Lake Superior will settle over Lower Michigan on Saturday. This will give the cooler and drier air a nudge over all of southern WI and allow for clearing skies from northeast to southwest through the day. Highs will be in the lower 70s. Low temps Sat night will be cooler, around 50. Patchy fog seems likely. Cronce && .LONG TERM... Issued 303 PM CDT Fri Aug 29 2025 Sunday through Friday: High pressure will hold strong over the Upper Great Lakes through Monday, and likely into Tuesday. Temperatures will gradually warm, with highs in the upper 70s Mon-Tue. Then an upper trough is expected to swing across the Upper Midwest and Great Lakes on Tuesday night or Wednesday. Depending on the time of day, thunderstorms could accompany the showers along the associated cold front. This is a robust system and there may be multiple shortwaves moving through before the upper trough finally moves out the next weekend. Cronce && .AVIATION... Issued 303 PM CDT Fri Aug 29 2025 The ceilings across southern WI are generally low-end VFR, but there are pockets of MVFR. An area of rain is crossing southern WI this afternoon. There are a few lightning strikes/thunderstorms in southwest WI where there was a brief clearing in the clouds. There is a potential for showers and isolated lightning to continue over southeast WI into the evening. On the back side of the area of rain, toward central WI, there is an area of IFR ceilings. There is low confidence about whether or not these will translate southeast into Madison or other areas. For now, kept the IFR ceilings out of the TAFs. Cronce && .MARINE... Issued 303 PM CDT Fri Aug 29 2025 High pressure centered over Lake Superior will drift southeast into Lower Michigan through Saturday and linger across the Great Lakes through the early part of next week. Low pressure is expected to develop across Ontario and pull a strong cold front from north to south across Lake Michigan on Wednesday, bringing a gusty northwest wind shift to all of lake. Gusty northwest winds will continue through most of Thursday with gusts near or just below gale force next Wednesday-Thursday across the open waters. Cronce && .MKX WATCHES/WARNINGS/ADVISORIES... WI...None. LM...None. && $$ Visit us at weather.gov/milwaukee Follow us on Facebook, X, and YouTube at: www.facebook.com/NWSMilwaukee www.x.com/NWSMilwaukee www.youtube.com/NWSMilwaukee