Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
191 FXUS63 KMKX 060304 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 1004 PM CDT Fri Jul 5 2024 .KEY MESSAGES... - Scattered to isolated showers linger into the evening. - Showers likely (60-70 percent chances) with chances for storms on Sunday and again on Monday. - Continued humid with temperatures near normal into next week. && .UPDATE... Issued 1004 PM CDT Fri Jul 5 2024 Scattered to isolated showers continue to fire across portions of south central and southeastern Wisconsin this evening. The The last of the available PVA from the 500 mb wave will be pulling out of the state over the next couple hours effectively bringing an end to the potential for further developing showers. The air column will remain saturated which will continue to make temperatures feel hot and humid. With the loss of instability past sunset, there is not a concern for any additional thunderstorms. With a cold front expected to pass tonight into early Saturday morning low level stratus clouds will redevelop across southern Wisconsin. For many this will be low impact unless you were banking on watching the sunrise or flying a plane. There will also be a small potential for fog to develop overnight into Saturday morning. The main area of concern for any patchy fog would be the western river valleys. Winds will decrease throughout the night and with the saturated ground conditions and high dewpoints, thus creating an environment for fog development. Not anticipating dense fog as we will not be cooling down enough or have clear enough skies for any radiational cooling to take place. Patterson && .SHORT TERM... Issued 300 PM CDT Fri Jul 5 2024 Tonight through Saturday night: A w-e line of showers and sct storms with heavy rain is ongoing along the w-e sfc trough and at the base of the 500 mb upper wave toward central WI. An outflow boundary is progressing swd and should reach the Madison area around 21Z and the MKE area btwn 2130-2200Z. The outflow should continue to initiate new shower and storm development given an uncapped airmass with sfc based CAPE of 1000-1300 J/KG. Cannot rule out isold urban and small stream flooding. The weak cold front will then follow with nwly sfc winds expected tnt-Sat AM. Given the moist sfc conditions and low level ATM, stratus clouds may re-develop tnt and continue into Sat AM. A weak sfc ridge will shift ewd across srn WI Sat afternoon but a weak 500 MB vorticity maximum will also pass. In addition a lake breeze will also form. Thus kept the slight chances (20 percent) for showers and storms in the afternoon with a marginally unstable airmass expected. Some clearing of skies will then occur Sat evening but clouds will increase again late. Gehring && .LONG TERM... Issued 300 PM CDT Fri Jul 5 2024 Sunday through Friday: A series of shortwave troughs will support mean upper troughing over the Upper MS River Valley and wrn Great Lakes for next week. Thus chances for showers and storms will be forecast each day with likely chances (60-70 percent) for Sunday and again Monday. Temps during the extended will be near normal with above normal relative humidity. Gehring && .AVIATION... Issued 1004 PM CDT Fri Jul 5 2024 VFR to IFR conditions are expected throughout the period. The last of the scattered to isolated rain showers will be coming to an end over the next couple of hours. The lower cloud decks with these showers (around 700 to 2,000 ft) will be sporadic until a large stratus deck begins to develop overnight. This stratus deck is expected to be within the same range (around 700 to 2,000 ft). There is some uncertainty on how expansive this stratus deck will be with current guidance suggesting it only impacts portions of southeastern and east central Wisconsin. This stratus deck is expected to persist into Saturday morning before gradually lifting to around 3.5kft by Saturday afternoon. Northwest winds will decrease tonight becoming light. The light northwest winds will continue through Saturday afternoon before becoming light and variable as surface high moves through the Great Lakes Region. Patterson && .MARINE... Issued 300 PM CDT Fri Jul 5 2024 Low pressure around 29.7 inches over central Lake Michigan will move into lower Michigan later this afternoon and to the lower Great Lakes late tonight. Light to modest southwest winds are expected over the southern half of Lake Michigan becoming westerly late in the afternoon, while modest northeast winds continue over the northern half. Winds will then turn north northwesterly across the entire lake this evening, lasting through Saturday morning, as the low moves across Lake Huron and southern Ontario. Winds return to a southerly direction Sunday into the early to middle portion of the week. Gehring && .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