871 FXUS63 KMKX 311924 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 224 PM CDT Fri May 31 2024 .KEY MESSAGES... - Rain showers likely (60-80%) Saturday, especially across southeast Wisconsin. Small chance (20%) for thunder in the afternoon Madison and westward. - Warm and humid conditions are expected through the first half of the workweek next week. - Expect daily chances (ranging from 40 to 80%) for showers and thunderstorms Monday through Wednesday. - Cooler conditions likely late week, with small (20-30%) shower and thunderstorm chances during the afternoon/evening hours. && .SHORT TERM... Issued 224 PM CDT Fri May 31 2024 Tonight through Sunday: Dry weather is expected to persist through tonight as high pressure centered over the Ohio River Valley gradually continues to head eastward. The milder airmass in place along with the increasing clouds tonight will keep low temps quite a bit milder than the last two nights. The bulk of models, particulary short term guidance, have trended wetter for Saturday. The GFS and Canadian solutions still keep the majority of the precip tied closely to the weak surface low passing by to the south, which would clip southeast Wisconsin. Most models show enough 850-700 mb temperature and moisture advection for widespread showers tomorrow though, especially across the southeast half of the forecast area. The 12Z HREF supports this with 60-90% of members producing measurable precip during the day tomorrow across the forecast area, again the highest percentage in the southeast. Bumped up precip chances for tomorrow as a result, leaning the forecast towards a consensus blend of the shorter term guidance. Went towards the cooler end of guidance for temps as well tomorrow given the expected clouds and precip. May see some breaks in the clouds northwest by later afternoon along with milder temps and some instability as the trough pushes into the area. Left a low thunder chance in this area as a result. A few showers may linger into early Saturday evening, but otherwise dry weather will return to the area as high pressure begins to build into the area. The dry weather will continue on Sunday as the high moves through. Temps will quickly recover behind the departing system, with above normal high temps cracking 80 most places away from Lake Michigan. Onshore winds will keep highs down into the 70s in the east, possibly even 60s for lakeshore areas given Lake Michigan water temps still in the 50s. DDV && .LONG TERM... Issued 224 PM CDT Fri May 31 2024 Sunday through Friday: Warmer temps will persist through the first half of next week along with increased moisture and shower/storm chances. Plenty of moisture and instability will be in place Monday as a shortwave moves through, so kept the higher NBM shower/storm chances in the forecast. Forcing will be weaker Tuesday, but a weak wrinkle or two in the flow may kick off afternoon/evening showers and storms as deeper moisture and instability linger across southern Wisconsin. Stronger forcing is still expected to move through Tuesday night into early Wednesday as the main trough/front pushes through the area. Bumped precip chances up a bit from 24 hours ago, as there is increasing confidence in the front timing, which is trending a bit faster. Temps are expected to fall back to at least normal values Thursday and Friday (if not cooler) behind the departed cold front. Models are showing weak waves in the large scale cyclonic flow across the region that may bring small (20-30%) chances of showers late week, mainly during the afternoon and early evening with daytime heating. DDV && .AVIATION... Issued 224 PM CDT Fri May 31 2024 Quiet weather will continue into tonight as high pressure gradually heads east out of the region. Mid and high level clouds will gradually increase from the west late today into tonight ahead of an approaching trough. The trough and associated surface low to the south are expected to bring showers to southern Wisconsin on Saturday, with gradually lowering ceilings as well. A few rumbles of thunder will be possible, mainly in the afternoon from Madison westward. DDV && .MARINE... Issued 224 PM CDT Fri May 31 2024 High pressure over the eastern Ohio River Valley this afternoon will continue to head eastward this evening into tonight. Light southerly winds will prevail between the departing high and an approaching trough of low pressure. A weak surface low will then pass to the south of the area Saturday, bringing rain showers to at least the southern half of the lake. Winds will likely shift to the east and then north as the low moves through the region, especially across the southern half of the lake. Light and variable winds are likely Sunday as high pressure briefly moves through the area. Winds will return to southerly early next week and also increase a bit ahead of the next approaching low pressure system. A chance for showers and storms will return to Lake Michigan during this period as well. DDV && .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