Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
021 FXUS63 KMKX 201528 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 1028 AM CDT Thu Mar 20 2025 .KEY MESSAGES... - A few other systems to watch for Friday and then again late Saturday into Monday. The latter will bring potential for a wintry mix and some snow. && .UPDATE... Issued 1025 AM CDT Thu Mar 20 2025 Low pressure continues to lift northeast while the northern edge of the high pressure gradually works its way into southern WI through the afternoon. Will see the northwesterly winds and gusts gradually come down in response. Otherwise, will be on the cooler side today with highs only topping off in the mid to upper 30s. Wagner && .SHORT TERM... Issued 325 AM CDT Thu Mar 20 2025 Today through Friday night: Snow will gradually push out of the CWA over the next few hours with the exception of some lingering light snow across far eastern WI as forcing from the upper low finally pushes east of the region. Another brief shortwave will slide through later today but since this will not have moisture with it, especially as high pressure nudges in, we expect to remain dry. The high pressure impinging on the departing low should allow for some breezy conditions in the morning hours before the gradient starts to weaken across the region. Relatively cool high temperatures should be expected today as the front has ushered in a cooler air mass but short term large scale ridging in addition to a system developing in the northern plains should bring back southerly winds by this evening. Into Friday, the surface low will track across Ontario and the western Great Lakes region with southwesterly winds becoming gusty into the afternoon. The entrance of this system into the region will likely (80-90%) remain dry as it struggles with moisture in the low to mid levels. By the late afternoon early evening the moisture will start to improve in the low to mid levels though not every model suggests enough improvement for precip. The best forcing with this system does appear to be with the shortwave aloft with strongest PVA in the afternoon, so as of right now the forcing and moisture are somewhat disjointed leading to the uncertainty in precip chances (30-40%) even into the evening when the moisture improves. The best chances will be further east during the early evening when some deformation and perhaps some PVA hanging on could bring some precip to the area. Right now, this looks to largely remain on the warm side with rain but if it does hang on a bit longer than expected some snowflakes may fall from this though no accumulation would be expected. Kuroski && .LONG TERM... Issued 325 AM CDT Thu Mar 20 2025 Saturday through Wednesday: Saturday looks to be a fairly pleasant, if cool day, with highs in the upper 30s east to low to mid 40s west. Shortwave ridging should support clearing for much of the day, with clouds starting to build in during the afternoon. Southeast winds will pick up Saturday night as low pressure moves into the Dakotas. Light precipitation will begin to overspread the area Saturday night, initially in the form of a mix of rain, drizzle/freezing drizzle, and snow. This should give way to mostly all rain during the day Sunday as temperatures warm above freezing, though some rain/snow mix may persist over the northeastern portions of the forecast area, where temperatures will be slowest to warm. The surface and upper level lows will move across central Wisconsin Sunday evening, with some wrap around snow possible Sunday night as the system departs. Additional cold advection snow showers are possible on Monday. Active northwest flow looks to continue into at least mid week, with near daily shortwave passages. Marginal temperature profiles will favor mixed precipitation at times. Boxell && .AVIATION... Issued 1025 AM CDT Thu Mar 20 2025 Clouds have cleared as the low pressure pushes off to the northeast and VFR conditions will prevail through the afternoon and tonight. Gusty northwesterly winds will gradually weaken through the afternoon as the ridge of high pressure works its way across southern WI through the evening. By Friday morning expect winds to turn more southerly ahead of a late afternoon/evening cold front. Will likely see gusts up to 20-25kt Friday afternoon along with increased rain chances and lower ceilings into the evening. Wagner && .MARINE... Issued 325 AM CDT Thu Mar 20 2025 Low pressure over eastern Ontario will continue NNE into northern Quebec later today. Gale force and storm force winds are forecast into the day today. A Storm Warning is in effect into the mid morning before the pressure gradient weakens enough that winds come down to gales. Gales will continue through the morning and lingering across the southern half of the lake into the early afternoon before pushing out as the low pressure system pushes far enough away. Nearshore gales will remain through the mid morning before likely needing a short period for a Small Craft Advisory to follow. Much lighter winds will arrive for late this afternoon and early evening as a ridge of high pressure quickly shifts across the lake. However, breezy south to southwest winds will also quickly develop late tonight and last through Friday ahead of an approaching cold front. The winds will shift to brisk northerly with the cold frontal passage Friday night. Some gales will be possible over the lake Friday. Small Craft Advisory will be needed Friday for these breezy southwest winds. Kuroski && .MKX WATCHES/WARNINGS/ADVISORIES... WI...None. LM...Gale Warning...LMZ261-LMZ362-LMZ364-LMZ563 until 1 PM Thursday. Gale Warning...LMZ080-LMZ366-LMZ565-LMZ567-LMZ669-LMZ671- LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874- LMZ876-LMZ878 until 4 PM Thursday. Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646 until 4 PM Thursday. && $$ 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