Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
174 FXUS63 KMKX 222358 AAA AFDMKX Area Forecast Discussion...UPDATED National Weather Service Milwaukee/Sullivan WI 658 PM CDT Wed Jul 22 2026 .KEY MESSAGES... - Dry and less humid through the rest of the work week. Muggy conditions return this weekend. - Showers and thunderstorms return to the forecast Saturday evening. Rounds of storms, possibly severe, are possible into the middle of next week. && .UPDATE... Issued 700 PM CDT Wed Jul 22 2026 Scattered to broken stratocumulus clouds may linger through a good portion of the evening, before dissipating overnight. High pressure will move southeast across the area overnight into Thursday morning, before shifting to the southeast in the afternoon and into Thursday night. Dry conditions are expected. Another round of scattered to mainly broken stratocumulus clouds are anticipated Thursday afternoon and early evening. Light and variable to calm winds overnight may lead to some fog in the Wisconsin River Valley and other low lying areas. A southeast lake breeze is expected again Thursday afternoon near Lake Michigan, with light southwest winds inland. Lows tonight in the lower 50s are expected over most inland locations, with middle to upper 50s close to Lake Michigan. Highs Thursday will be mainly in the upper 70s, turning a little cooler near the lake in the afternoon. Wood && .SHORT TERM... Issued 132 PM CDT Wed Jul 22 2026 Rest of Today through Friday: There were more widespread cumulus clouds and lightly stronger winds across southern WI today than what was previously expected, but our forecast highs remain on track at around 74 to 75 (except a degree or two cooler along the lakeshore due to the lake breeze). With surface high pressure over southern WI tonight, expect efficient radiational cooling and another night with lows in the lower 50s. Light south-southwest winds are expected Thursday as the high begins to exit. Inland highs will be in the upper 70s. Expect a lake breeze to drop the afternoon temps a couple degrees near the lakeshore. Steadier southerly winds will develop Friday as a surface trough approaches from the Northern Plains, but a lake breeze is still expected. High temperatures will be around 80 with quiet weather continuing. Cronce && .LONG TERM... Issued 132 PM CDT Wed Jul 22 2026 Saturday through Wednesday: A weak surface trough stemming from a broad upper low and associated surface low crossing Ontario will sag through WI on Saturday. This will mainly bring a wind shift from southwest to west, but the 850-700mb warm air advection and weak surface convergence (enhanced by the lake breeze) may help trigger a few showers or thunderstorms in the afternoon and evening. Saturday high temps will be in the mid 80s with dewpoints creeping back into the 60s. It will feel warm and humid. Sunday afternoon and night, and potentially into Monday, look to bring some more unsettled weather into the area. Overall, there will be another broad, warm and humid ridge over the center of the country. This ridge should push into at least the southwest half of WI on Sunday and bump our highs to around 90 with dewpoints pushing 70 (very warm and humid). Meanwhile, a mid level shortwave trough is expected to slide across the US/Canadian border from MN to Lake Superior to Lake Ontario, coincident with an 850mb baroclinic zone. It looks like ingredients (moisture, instability, shear) will be in place over at least central WI Sunday afternoon/night for the potential for a round of severe storms. The forcing would be the nose of the low level jet and shortwave trough. There is more uncertainty for how far south the storms will get Sunday night. The ridge will hang on over the central U.S. through much of the next week. Several more shortwave troughs are expected to track across the Upper Great Lakes from Monday through Wednesday, so additional rounds of storms (possibly severe) are likely for central and southern WI. Each round will depend on how the previous day`s storms panned out. This looks to be an active weather pattern setting up for WI. Cronce && .AVIATION... Issued 700 PM CDT Wed Jul 22 2026 Some broken ceilings around 6000 to 8000 feet AGL may linger into this evening, with scattered clouds mixed in, before dissipating overnight. High pressure will move southeast across the area overnight into Thursday morning, before shifting to the southeast in the afternoon and into Thursday night. Dry conditions are expected. Another round of scattered to mainly broken stratocumulus clouds are anticipated Thursday afternoon and early evening. Any ceilings should be in the 5000 to 7000 foot AGL range. Light and variable to calm winds overnight may lead to some fog in the Wisconsin River Valley and other low lying areas. A southeast lake breeze is expected again Thursday afternoon near Lake Michigan, with light southwest winds inland. Wood && .MARINE... Issued 132 PM CDT Wed Jul 22 2026 Light and variable winds are expected tonight into Thursday as high pressure around 30.1 inches crosses Wisconsin and southern Lake Michigan. Look for southerly winds to develop by Friday as the high progresses into the northeastern United States. A 29.5 inch low pressure will move quickly from the Canadian Great Plains toward Quebec Friday through Saturday, maintaining south to southwest winds over Lake Michigan. The low will attempt to pull a cold front into the western Great Lakes on Saturday, with the boundary slowly advancing south across the waters through Saturday night, which will result in returning thunderstorm chances. A stationary front is expected to sit across Lake Michigan through the middle of next week, so there will be switches between northerly and southerly winds at times. This front will be the focus for several rounds of thunderstorms, possibly severe. 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