Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
638 FXUS63 KMKX 122015 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 315 PM CDT Mon Aug 12 2024 .KEY MESSAGES... - Low chances (15 to 20%) of isolated showers and weak thunderstorms east central WI this afternoon. - Very low (10%) chances for isolated showers and weak thunderstorms along the lake breeze Tuesday (lakeshore and adjacent counties only). - Aside from the above, dry conditions expected to continue through Wednesday as high pressure influences the region. - Chances for showers and thunderstorms (30 to 80%) from Wednesday night into this weekend. Highest chances (60 to 80%) for rainfall are Thursday / Thursday night. && .SHORT TERM... Issued 315 PM CDT Mon Aug 12 2024 Tonight through Tuesday night: An axis of agitated cumulus clouds is evident across northern WI at the moment, with isolated shower and weak thunderstorm activity. Thus, areas in east-central WI still have a 15 to 20% chance for a shower or weak / brief storm this afternoon and evening. Storm chances and cumulus clouds will break down this evening, leaving skies mostly clear for late tonight. Forecast soundings are quite dry for the overnight hours tonight aside from some lingering moisture at the top of the residual layer and perhaps just enough moisture aloft for some cirrus, suggesting good sky viewing conditions tonight. Daytime highs climb 1 to 3 degrees higher on Tuesday (to the low 80s), and with water temperatures in the low to mid 70s, a weak lake breeze will likely develop and move about 1 county inland. Said areas are under a roughly 10% chance for a shower or weak thunderstorm Tuesday afternoon. Once again, shear and instability are too weak for organized / strong storms. Sheppard && .LONG TERM... Issued 315 PM CDT Mon Aug 12 2024 Wednesday through Monday: Dry and pleasant weather continues into Wednesday, with temperatures similar to Tuesday and a synoptic southeasterly breeze developing ahead of a low pressure system, moving in from the Great Plains. Strong WAA and moist advection ahead of the approaching low bring scattered showers and thunderstorms. Storm chances begin Wednesday night into Thursday night, with chances continuing into the weekend as the low departs eastward. Main window for the highest rain chances (60 to 80%) is Thursday through Thursday night. It is too early to diagnose the severe potential of this setup, but a soaking rain appears likely. The early Thursday AM arrival of the system will likely limit the available CAPE. Sheppard && .AVIATION... Issued 315 PM CDT Mon Aug 12 2024 VFR conditions expected to continue through Wednesday. A 15 to 20% chance for isolated showers and thunderstorms in east central WI this afternoon through this evening. Scattered diurnal cumulus clouds (4000 ft to 5000 ft) will clear out as daytime heating shuts off, leaving skies mostly clear tonight. Nearly calm winds tonight, light and variable on Tuesday with a weak (5 to 10 kt) southeast lake breeze Tuesday afternoon. Said lake breeze merits a 10% chance of isolated showers and thunderstorms along it, which will not be put in TAFs unless confidence increases. Diurnal cumulus at the same altitude (4000 to 5000 ft) likely to redevelop on Tuesday with scattered coverage, perhaps some broken coverage along the lake breeze. Sheppard && .MARINE... Issued 315 PM CDT Mon Aug 12 2024 High pressure of 30.0 inches centered over Wisconsin this afternoon will continue to move eastward through Tuesday allowing for light and variable winds. Winds will become east to southeasterly and accelerate on Wednesday as low pressure of 29.7 inches develops across the Central Plains and lifts northeast towards the Great Lakes, moving through the region on Thursday and Friday while deepening to 29.5 inches. Shower and thunderstorm chances exist across Lake Michigan on Thursday and Friday due to this low. Westerly to northerly winds expected this weekend as the low departs eastward. Sheppard && .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