397 FXUS63 KMKX 020915 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 415 AM CDT Mon Jun 2 2025 .KEY MESSAGES... - Smoke aloft from wildfires will continue to move through southern WI through Monday night. Any surface smoke will be brief and very limited. - Widespread showers and scattered thunderstorms are expected (80-90%) from Tuesday afternoon through early Wednesday morning. Moderate to locally heavy rainfall is possible along with a strong storm or two. && .SHORT TERM... Issued 415 AM CDT Mon Jun 2 2025 Today through Tuesday night: South winds will increase a bit today as pressure falls occur along the advancing sfc trough and cold front that will reach a line from central MN to the central high plains by 00Z Tue. Aloft, the upper ridge over MN will move across WI and the wrn Great Lakes in response to a shortwave trough moving across MT. The sky conditions will mostly be dominated by smoke in the mid to upper levels but should be translucent. Nevertheless, the smoke could keep high temps down a bit. Highs in the lower to middle 80s today and low relative humidity, cooler at the lakefront. Southerly winds will keep temps mild tnt as the pressure gradient increases followed by breezy sly winds on Tue as daytime heating will contribute to mixing and winds gusts of 30-35 mph. The cold front will enter nw WI Tue AM and eventually reach locations north and west of Madison by 00Z Wed. Humidity will increase as a plume of PWs near 2 inches shifts into the area. Mid level lapse rates will be weak and best estimates for MLCAPE are around 500 J/KG for the afternoon. Mdt deep layer shear is expected with fairly strong wind fields still at 850 mb so momentum transfer is a concern for the stronger storms. Overall the severe threat appears to be isolated at this time. There is also some concern for heavy rainfall and potential flooding as the frontal passage will slow Tue nt in response to a shortwave trough tracking from ne KS into se WI Tue nt. This upper wave is shearing out a bit with time and the pressure fields are weakening, but given the moist soundings it should give some boost to rainfall for late evening into the overnight. Overall the rivers are low and soils are fairly dry, while there is low confidence rainfall rates will sustain high levels long enough for flash flooding. Widespread one inch rainfall amounts are expected with 20-40 percent probs for 2 inches over far srn WI. Gehring && .LONG TERM... Issued 415 AM CDT Mon Jun 2 2025 Wednesday through Sunday: The shortwave trough and northeast-to-southwest oriented frontal boundary will exit far se WI Wed AM, although there is some uncertainty on the timing and potential for lingering rain. High temperatures will drop back into the upper 60s to lower 70s for the day. The boundary will stall over central IL, IN, and southeast Michigan through Wednesday night and perhaps into Thursday. This is due to an upper low sitting over Hudson Bay. Therefore, our weather in southern WI should be mostly dry from Wednesday afternoon through Thursday, although some uncertainty remains. Several shortwaves will track across the northern part of the country from Thursday night through Sunday. This gives us an unsettled weather pattern. Each shortwave will bring a chance for showers and thunderstorms, but the timing and strength of each one is not possible for models to resolve this far in advance. The main thing to note is that there will be a day or two at a time without rain, the rain amounts look fairly light without a decent moisture source, and we will be able to resolve timing better as we get closer. Temperatures will be around normal for this time of year, in the lower to mid 70s. Gehring && .AVIATION... Issued 415 AM CDT Mon Jun 2 2025 VFR conditions will continue today and tonight with a layer of smoke in the mid to upper levels of the atmosphere. LLWS will develop late this evening into the overnight via a swly low level jet of 40-45 kt. Gehring && .MARINE... Issued 415 AM CDT Mon Jun 2 2025 South winds will increase today becoming breezy over the north half of the lake this afternoon, then expanding to all of the lake tonight and Tuesday. This is in response to a Canadian cold front approaching from the northern Great Plains. The cold front will cross Lake Michigan late Tuesday night into Wednesday morning with modest southwest winds shifting to the north. Weak high pressure will then settle over the lake later on Wednesday and into Thursday. Light and variable winds are forecast during this time. Gehring && .MKX WATCHES/WARNINGS/ADVISORIES... WI...None. LM...None. && $$ Visit us at weather.gov/milwaukee Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/NWSMilwaukee www.twitter.com/NWSMilwaukee www.youtube.com/NWSMilwaukee