Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
365 FXUS63 KMKX 190341 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 941 PM CST Tue Nov 18 2025 .KEY MESSAGES... - Dense, freezing fog may expand into portions of east central Wisconsin overnight. - Slight chances (~15-25%) for rain on Thursday, particularly across the east. - Temperatures hovering near or just above normal this weekend into early next week. && .UPDATE... Issued 941 PM CST Tue Nov 18 2025 The areas of drizzle over much of southern WI and the wintry mix toward Fond du Lac and Sheboygan exited the area this evening. Skies are clearing over east central WI. There is still question about how far the clearing will get. The clear skies are allowing for radiational cooling, calm winds, and fog development. With temps below freezing in this area, freezing fog with a light coating of frost/ice on roadways may occur and cause a few slick spots, mainly on elevated surfaces like bridges. We will continue to monitor the trends as fog expands from the Fox River Valley tonight and issue a Dense Fog Advisory as needed. Cronce && .SHORT TERM... Issued 305 PM CST Tue Nov 18 2025 Tonight through Wednesday night: Synopsis/Mesoanalysis: An upper disturbance is crossing southern Wisconsin this afternoon, resulting in cloudy and chilly conditions. Tied to a band of frontogenesis at the 700 mb level, steady precipitation is lingering over far northern portions of Fond du Lac and Sheboygan counties. Despite surface temperatures just above the freezing mark, dynamic cooling has allowed for the majority of this precipitation to fall in the form of snow, with minor accumulations having been noted on mostly grassy surfaces. Snow will continue through mid-afternoon over northern Sheboygan and Fond du Lac Counties, with additional minor/slushy accumulations possible. Affiliated with broad ascent from the passing disturbance, light sprinkles and rain showers will continue into the evening commute further south. High pressure will build over northern Lake Michigan tonight, allowing conditions to dry out after the dinner hour. Cloud cover will linger through the day on Wednesday, keeping temperatures cool across the region. Rest of this Afternoon: Light sprinkles and rain showers will continue. Steadier snow & rain/snow mix will remain possible over northern Fond du Lac and Sheboygan Counties for the next couple hours. Model analysis shows the best overlap of lift and moisture within the DGZ shifting out of these areas, but can`t rule out some additional minor/slushy accumulation (~a couple tenths) through 4 PM. Tonight: Conditions will dry out as high pressure builds over northern Lake Michigan. Occurring in response to the high, do anticipate a push of drier air to work into southern Wisconsin after midnight. This should allow for some breaks in the clouds to the north of I-94. Will need to monitor the progression of the clearing line, as an earlier arrival could combine with decreasing surface winds to support patchy fog development. Model guidance depicts better fog signals to the north of the area, so have withheld any mentions in the afternoon update. Will nevertheless be monitoring trends through tonight & adjust the forecast if trends warrant. Quigley && .LONG TERM... Issued 305 PM CST Tue Nov 18 2025 Thursday through Tuesday: Synopsis: Split flow will prevail across the CONUS through much of the long term period, with occasional phasing attempts resulting in slight chances (~15-30%) for precipitation on Thursday and once again Monday night through Tuesday. Thermal profiles will be plenty warm enough for all rain in any Thursday precip, with preliminary forecast soundings suggesting all rain once again during the Monday night-Tuesday time frame. Following above-normal high temperatures on Thursday, a weak frontal passage will knock readings back toward normal Friday into Saturday. Temperatures will then trend back above normal Sunday into the beginning of next week. Quigley && .AVIATION... Issued 941 PM CST Tue Nov 18 2025 Ceilings are gradually improving this evening, with IFR bases around 600 ft across south central WI and MVFR ceilings around 1500 ft over southeast WI. Clouds are clearing quickly over east central WI, including Fond du Lac and Sheboygan. This is an area to watch for expanding dense fog with visibility of a quarter mile or less. With temperatures below freezing, slick spots may develop on surfaces, especially elevated. The edge of clearing should slow down, so not expecting clear skies from Wisconsin Dells to Watertown to Burlington. Waukesha and Kenosha are uncertain, but Milwaukee should clear out. The low level moisture will remain stationary over south central WI through the day Wednesday, and ceilings may not even rise to MVFR greater than 2000 ft. Cronce && .MARINE... Issued 305 PM CST Tue Nov 18 2025 1008 mb low pressure is positioned over the middle Mississippi Valley this afternoon, resulting in breezy east winds across the southern half of Lake Michigan. Winds are lighter further north, where higher surface pressure is in place. Winds will gradually taper across all of the Lake Michigan late tonight through Wednesday as 1024 mb high pressure builds across the western Great Lakes. 1004 mb low pressure will develop along the Ontario-Manitoba border Wednesday night, deepening to near 1000 mb over the Hudson Bay by Thursday afternoon. The low`s development and progression will result in a southwest wind shift across Lake Michigan, with winds becoming gusty late Thursday morning and afternoon. Highest gusts are expected over the northern third of the waters, where 20-25 kt readings are currently forecast. Gales aren`t expected, though trends will continue to be monitored. A cold front will cross the waters Thursday night, resulting in northwest winds Friday into Saturday morning. Rain showers will continue into this afternoon over the southern half of Lake Michigan. A few wet snowflakes could mix in over the middle portion of the lake. Additional rain is possible Thursday, particularly over the northern third of the waters. Breezy east to northeast winds will result in continued elevated wave heights in nearshore zones into this evening. Waves are expected to be highest from Milwaukee south to Winthrop Harbor. A Small Craft Advisory remains in effect until 9 PM CST this evening from Port Washington to Milwaukee, and until 12 AM CST from Milwaukee south to Winthrop Harbor. Depending on trends, advisories may be able to expire early. Conditions will be monitored through this evening. Quigley && .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