Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
027 FXUS63 KMKX 052102 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 402 PM CDT Wed Jun 5 2024 .KEY MESSAGES... - Additional showers and thunderstorms late this afternoon and evening as a secondary front sweeps through. - Windy, showery for Thursday. Continued breezy into the weekend, but drier. && .SHORT TERM... Issued 402 PM CDT Wed Jun 5 2024 Tonight through Thursday night: A robust shortwave trough currently pushing into west central WI will be a trigger for thunderstorm development along the leading edge over the next hour or two. The cluster of showers and storms will track across southern WI this evening, entering the Dells area around 6 PM and exiting the Milwaukee area around midnight. With 500 j/kg CAPE strong synoptic dynamics to support high bulk shear values, there is a small risk for a severe- level wind gust or two this evening. Gusty westerly winds will develop Thursday morning and persist through late afternoon, with peak gusts around 30 mph. There is a chance for a few higher gusts if we end up mixing a little deeper than expected. With steep low level lapse rates, we can expect shallow showers to develop in the afternoon. The more widespread showers will be over northern WI where a more robust shortwave will be tracking. Cronce && .LONG TERM... Issued 402 PM CDT Wed Jun 5 2024 Friday through Wednesday: The closed upper low over the Upper Great Lakes will gradually shift east Friday, but the cyclonic flow will allow for another day of diurnal cumulus clouds and fairly gusty northwest winds. There should be some weak ridging over southern WI Friday night. For Saturday, we get into a more complicated scenario that will bring rain chances to southern WI in both the morning and afternoon. Another upper low will set up over Lake Superior Saturday morning. A shortwave trough rounding the base of it will slide across southern WI the first part of the day. Warm air advection ahead of this shortwave will support development of showers along a surface front that will likely be draped across northern IL. Those showers should extend north of the front through a good portion of southern WI during the morning hours. By the afternoon, the cyclonic flow over northern and at least part of southern WI will lead to additional scattered showers. Depending on the lapse rates and moisture, the conditions may allow for a few thunderstorms, but confidence is low at this time. The last gasp of this upper trough will drop through WI Sunday morning. The cyclonic flow and steep mid level lapse rates will yet again allow for scattered showers and probably some thunderstorms. The next upper trough and associated surface trough is expected to cross the Upper Great Lakes on Tuesday, bringing a chance for showers and storms. Cronce && .AVIATION... Issued 402 PM CDT Wed Jun 5 2024 A round of showers and thunderstorms will spread into the area from west to east this evening and exit around midnight. Gusty winds up to 50 kt are possible with any stronger storm. Less confidence for thunder all the way to the lake toward midnight. Look for breezy westerly winds on Thursday with some scattered showers under VFR ceilings. Cronce && .MARINE... Issued 402 PM CDT Wed Jun 5 2024 Thunderstorms are possible tonight as an upper level disturbance tracks across Wisconsin and Lake Michigan. A secondary cold front will move across the lake overnight, with gusty westerly winds developing Thursday. A large area of low pressure will gradually move through southern Canada, just north of the Great Lakes, through the end of the week. Winds will remain westerly and breezy through this period. Showers will be possible at times late week as shortwaves move through the broad cyclonic flow across the region. Cronce && .MKX WATCHES/WARNINGS/ADVISORIES... WI...None. LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646...10 AM Thursday to 10 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