Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
594 FXUS63 KMKX 120847 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 347 AM CDT Thu Jun 12 2025 .KEY MESSAGES... - Periodic shower and thunderstorm chances across southern Wisconsin this morning will shift northward into central Wisconsin by this afternoon. - Additional chances for more scattered showers Friday and Saturday. There will be breaks/lulls in the rain. && .SHORT TERM... Issued 347 AM CDT Thu Jun 12 2025 Today and Tonight: While there has been a lull in thunderstorm activity this morning across southern Wisconsin, rain continues to funnel in from the west. Storms continue to develop and fire along 850mb frontogenesis and WAA in northern Iowa and stream east along the front. The sfc front is currently along the WI/IL border and will stay stagnant across the state boundary through today. CAPE, instability, and shear are all low to zero across southern Wisconsin, which is quickly decaying all storms/showers that move in. Mid level WAA will again kick in to our west and push the mid level front northward. As this boundary pivots north, so to will the rain/storm potential. With the sfc front to our south and a solid deck of clouds overhead, the southern Wisconsin environment will struggle to recover and there is not any triggers for convection expected to move through. This means that any rain we get is coming from Iowa and Minnesota (where there is better instability and lift). With the mid level boundary moving northward its likely (60-80%) that southern counties and eastern counties remain dry through today and into Friday afternoon. Should we actualize that 20-40% chance for isolated showers to develop across the area the main driver will be diurnal heating and good moisture. Either way, not anticipating any stronger storms. Heading into Friday morning guidance is suggesting another push of mid level WAA moving northeast across northern Iowa and into southwest/west central Wisconsin during the early morning hours. Should we get this wing of WAA, there will be a good chance for showers and a few thunderstorms to develop along it and continue northeast. Otherwise mostly dry weather is expected through much of the day Friday as the sfc front will be to our south and the mid level support (baroclinic zone) will be to our north. Friday night into early Saturday morning an inverted trough is expected to swing through the region providing a good force of lift to trigger another round of showers and storms. There is some uncertainty on track and how strong this inverted trough will be so kept POPS around (20 to 35%). While we don`t have great chances for rain the next couple days the chances are non zero, so bring a jacket/umbrella if your out and about. When thunder roars go indoors. Patterson && .LONG TERM... Issued 347 AM CDT Thu Jun 12 2025 Saturday through Wednesday: With the 850mb baroclinic zone sitting over central WI and then a subtle surface trough dropping through southeast WI, there is uncertainty about precip chances on Saturday. To add to that uncertainty, a weak upper trough will still be lingering over the IL and Ohio River Valley area. Southern WI may be in the warm sector for a time on Saturday, and mid level lapse rates would be steep enough to allow for some instability, but enough forcing would be in question for isolated showers and thunderstorms. A few showers could develop along the weak cold front dropping in from the northeast Saturday afternoon, although the moisture source and overall synoptic forcing will be minimal. Surface high pressure will take hold Sunday and Monday so our weather should be quiet. Temperatures will continue to be slightly below normal Sunday, ranging from the upper 60s near the lake and upper 70s well inland. Expect temps to be a notch warmer Monday as the upper level ridge nudges closer. The GFS tries to develop a storm complex over ND on the top of that ridge and race it through MN and central/southern WI Monday night. The ECMWF hints at this potential complex but diminishes it by the time it gets here. A shortwave trough or series of them is then expected to track across the Northern Plains Tuesday into Wednesday. This could bring a few rounds of showers and thunderstorms to southern WI, but timing and intensity remain very uncertain. Cronce && .AVIATION... Issued 347 AM CDT Thu Jun 12 2025 VFR conditions are expected through the period. Mid to high level clouds will remain across southern Wisconsin through Friday. An area of rain showers in northern Iowa this morning will continue east into southern Wisconsin. Rain and storms will weaken as they move through. Additional showers/storms will develop through the morning into the afternoon shifting northward over time. Late this afternoon and evening showers/storms are expected to be across west central and central Wisconsin. Then rain/storms should stay in northern and central Wisconsin overnight. Ceilings around 7 to 10 kft are expected with any precipitation. Higher ceilings are expected in areas that remain dry. Light northeast winds this morning will gradually become easterly by tonight. Lakeshore terminals could see some breezy winds coming off the lake with gusts of 20 to 25 mph possible. Patterson && .MARINE... Issued 347 AM CDT Thu Jun 12 2025 Low pressure in Ontario will continues east into the northern New England States today as stationary front sits across the far southern lake. This stationary front will remain over the far southern portions of the lake through Saturday. Light to moderate northeast to east winds are expected for areas north of this frontal boundary. Areas south of the front can expect light southeast winds. This afternoon into tonight northeast winds will again approach Small Craft Advisory levels with gusts of 20 knots possible. Rain and storms will be possible across mid lake this afternoon and evening. This front will drift southward and clear the lake early Saturday as low pressure moves into the southern Great Lakes Region from the Rockies. Light to north to northeast winds are expected across the entire lake Saturday and Sunday once the front has cleared. Additional chances for rain Friday and Saturday. Patterson && .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