


Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
203 FXUS63 KMKX 200740 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 240 AM CDT Wed Aug 20 2025 .KEY MESSAGES... - Overall drier and less humid through the rest of the week. - Fog is expected inland from Lake Michigan this morning. Areas near and west of Madison may see some dense fog. - Chance for a few isolated to scattered sprinkles area-wide through this afternoon. - A Beach Hazard Statement is now in effect from 7pm today to 4am Thursday for waves of 3 to 5 feet and dangerous currents. It is advised to stay away from piers and breakwalls during this time, and avoid swimming at Lake Michigan beaches during this time period. && .SHORT TERM... Issued 240 AM CDT Tue Aug 19 2025 Today through Tonight: Some surface moisture convergence and impacts from an inverted surface trough have allowed for some light to moderate showers across western parts of the CWA this morning. This will likely gradually weaken and dissipate as it travels SSE, especially as the inverted trough slides south with higher pressure pushing in behind. In addition with another night of radiational cooling with moisture getting trapped under the inversion expect some fog, becoming more impactful further west. Not expected to see widespread dense fog at this time but further west may see some patches to areas of dense fog. Into the daylight hours, fog should quickly dissipate across the CWA. By the late morning, with increased northeast winds across the lake we should see some lakeshore convergence with lighter and more northerly inland winds. With plentiful moisture from the surface to 850mb and some semblance of a convergence boundary even in large scale models now it would seem likely at least isolated sprinkles to even a few showers would be possible. Soundings suggest the strongest convergence will be right around 900mb with fairly strong omega present. Further west models are also pointing to additional chances for light showers to drizzle as another surface level inverted trough factors in. Soundings are much less favorable with much weaker forcing but this forcing appears focused right at the surface. Some large scale models show this mild surface convergence. The key is that low level moisture will be slightly better further west thus making a few showers/pockets of drizzle possible. Overall drier conditions will begin to take over by the late afternoon through the night as the high pressure begins to become more established with drying low to midlevel air. Beach Hazards Statement is now in effect 7pm today to 4am Thursday for breezy onshore winds causing waves from 3-5 feet. This will impact Milwaukee, Racine and Kenosha beaches. The waves during the day today have come down quite a bit and thus we are holding off on the Beach Hazard until later this evening. Expect dangerous swimming conditions especially for north facing beaches, areas near piers and/or breakwalls which will be most vulnerable to these dangerous currents. Kuroski && .LONG TERM... Issued 240 AM CDT Tue Aug 19 2025 Thursday through Tuesday: Weather is expected to remain quiet and mostly sunny Thursday/ Thursday night as high pressure moves overhead and ridging remains entrenched across the region. The upper level ridge and associated sfc high pressure will pull east heading into Friday morning as a trough moves in from the northwest. This trough and the associated sfc low in Saskatchewan will move easterly across the Northern Great Lakes and Ontario. The path of the sfc low will have int moving from central Saskatchewan toward James Bay. A cold front associated with this low will move southeast across Wisconsin Friday bringing some scattered rain and a few thunderstorms. The cold front is expected to move through Friday evening, but convergence along the frontal boundary looks fairly weak. Moisture is also expected to be low as there isnt expected to much of a moisture return ahead of the front. Winds will briefly return to southerly Friday morning, but winds will be light. PWATs are therefore also low. Overall not a great setup for rain so many people may end up in a hit or miss scenario with light rain and a few claps of thunder. POPs are around 10-25% as this cold front moves through. Cool and dry conditions return behind the cold front. Winds will remain north to northwesterly from roughly Saturday through early next week as a ridge builds in from the west and a large occluded extra tropical cyclone remains in the Hudson Bay area. Temperatures are expected to fall day by day with highs in the mid to upper 70s on Saturday becoming upper 60s to low 70s by Monday. Patterson && .AVIATION... Issued 240 AM CDT Tue Aug 19 2025 Scattered showers currently across parts of southwest WI with some moderate showers possible that could temporarily reduce VSBYs these will gradually shift SSE early this morning and push out around daybreak. In addition fog is expected to develop across much of southern WI this morning likely impacting VSBYs. Fog is expected to become more impactful further west but the impact of the current showers and corresponding CIGS may impact how impactful fog can become. Not expecting to see widespread dense fog at this time but further west may see some patches to areas of dense fog. Fog is expected to dissipate quickly after daybreak with the sun burning it off. MVFR/IFR CIGS will be expected to develop and expand early this morning as well, especially where they are ongoing in southeast WI right now. This too is expected to begin clearing out after daybreak but will take a bit more time and may persist through much of the morning and lingering into the afternoon. A few isolated to scattered showers/sprinkles will be possible during the day today primarily in east central WI and closer to the lake but will be possible across most of southern WI through the mid afternoon. Quieter conditions will return later this afternoon through the night. Some uncertainty as to whether there will be another chance for fog or low CIGS tomorrow night but models are certainly indicating lesser concern for this risk at this time. Kuroski && .MARINE... Issued 240 AM CDT Tue Aug 19 2025 High pressure will remain over the Great Lakes through Friday. A breezy period of northerly winds will persist through today as the high moves in behind a retreating low pressure. A few showers on the west side of the lake will be possible. Light to moderate north winds are then expected tonight into early Friday, before winds turn southerly Friday morning head of an approaching cold front. Breezy north to northeast winds will bring a period of higher waves this evening through late tonight with waves up to 5 feet for the southern 3 tiers of the nearshore. A Small Craft Advisory remains in effect for this period but has been delayed due to waves really lacking during the day today in the latest forecast. Kuroski && .MKX WATCHES/WARNINGS/ADVISORIES... WI...Beach Hazards Statement...WIZ066-WIZ071-WIZ072...7 PM Wednesday to 4 AM Thursday. LM...Small Craft Advisory...LMZ644-LMZ645-LMZ646...7 PM Wednesday to 4 AM Thursday. && $$ 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