NWS Milwaukee Forecast Discussion
515 FXUS63 KMKX 150242 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 942 PM CDT Sat Jun 14 2025 .KEY MESSAGES... - Scattered showers and a few storms may move into areas west of Madison later tonight into Sunday morning. Chances for showers and storms linger in south central to east central Wisconsin Sunday afternoon and night, though confidence in this is low to moderate. - Chances for showers and thunderstorms at times Monday into next week, with the better chances Tuesday into Wednesday night. && .UPDATE... Issued 940 PM CDT Sat Jun 14 2025 No major changes to the going forecast, aside from a thin broken line of rain showers tracking eastward through east central WI (forced by a weak 700mb thermal trough). This should track east from Fond du Lac / Sheboygan / Washington / Ozaukee counties over the next 3 hours, with any rain barely reaching the ground due to evaporation (only planning to add 25% precip chances unless surface obs warrant higher values). Models resolve the existing clusters of thunderstorms over eastern MN / IA diving south overnight and largely dissipating towards midnight. Then from late tonight into early Sunday morning, additional storm clusters redevelop in the same area, nudging a little further east this time into southwestern WI. Precip chances remain at 25-45% west of a Monroe to Green Lake WI line late tonight through much of Sunday. Sheppard && .SHORT TERM... Issued 249 PM CDT Sat Jun 14 2025 Tonight through Sunday night: CAMs suggest that scattered showers and a few storms may develop later tonight in southern Minnesota or northern Iowa, and may shift into areas west of Madison overnight and into south central Wisconsin Sunday morning. This would be driven by modest but focused 850 mb warm air advection. Kept 30 to 50 percent PoPs mainly west of Madison for this possibility, with smaller chances over the rest of south central Wisconsin. Instability is rather weak, so would expect more shower activity than storms. Confidence remains low to moderate here, so PoPs will need adjusting as we get closer to this period. Otherwise, quiet conditions are forecast elsewhere tonight into Sunday morning. Lows in the middle 50s east to around 60 far west are expected. More showers and storms may develop Sunday afternoon with peak heating across southern Minnesota and/or northern Iowa, as the focused warm air advection tries to set up there. It tries to extend into west central and northern Wisconsin Sunday night, with possibly more showers and storms developing there. Again, there is uncertainty with what and where any showers and storms occur, and some CAMs and synoptic scale models keep the forecast area dry or mostly dry, as the more focused 850 mb warm air advection remains to the west and northwest. Kept 20 to 40 percent chances for now in the forecast from south central to east central Wisconsin, and will need further adjustments once trends become more clear. Highs Sunday should reach into the upper 70s to lower 80s inland, with cooler 60s near Lake Michigan with onshore winds. Dew points should climb into the lower 60s inland, so it should feel a little more humid. Wood && .LONG TERM... Issued 249 PM CDT Sat Jun 14 2025 Monday through Saturday: Warmer and more humid conditions should move into the area Monday, though southeast winds near the lake should keep those areas cooler in the afternoon. Models seem to be showing a warm/stationary front west to east across northern Wisconsin Monday/Monday night, with possibly some weak differential CVA pushing through the area Monday. Not much upward vertical motion near the surface during this time, so not sure if there will be enough for showers and storms to develop. Kept 30 to 40 percent PoPs going for now, as instability increases but deep layer bulk shear remains weak. Confidence remains low, so adjustments to the PoPs will be needed. Models now seem to bring a cold front southeast toward the area Tuesday afternoon and evening, with the front possibly being over or southeast of the area by Wednesday as the surface low moves northeast along it. Still a lot of uncertainty here as well with how things will evolve, so kept NBM PoPs going for now. Still have 60 percent or higher PoPs generally later Tuesday night into Wednesday. This period should have better deep layer bulk shear and enough instability for the possibility of stronger storms, but the timing and placement of all of these features will dictate the risk. Will continue to watch this period. Ensembles are suggesting warm air advection on south to southwest winds later in the week bringing very warm and humid conditions into the area by Saturday and perhaps lasting for a few days. Will continue to monitor temperature trends here. Wood && .AVIATION... Issued 940 PM CDT Sat Jun 14 2025 Nearly calm / light east to northeast winds expected overnight, with light east to southeast winds for Sunday. A broken line of very weak rainshowers currently tracking east through east- central WI over the next 3 hours. Otherwise, dry weather and VFR through tonight. A 25-45% chance for scattered showers and thunderstorms in southwestern WI late overnight through Sunday, mainly west of a Monroe to Green Lake WI line. Scattered to broken clouds over 25,000 ft expected Sunday, with the shower / storm activity to the west forming VFR ceilings generally over 4,500 ft (though some brief periods of MVFR ceilings cannot be ruled out. Sheppard && .MARINE... Issued 249 PM CDT Sat Jun 14 2025 High pressure around 30.3 inches along the Ontario and Quebec border will keep winds primarily easterly to northeasterly through the rest of the weekend. Weak low pressure around 29.9 inches in southern Illinois will push east tonight into the Ohio River Valley and weaken on Sunday. Chances for showers and thunderstorms are forecast at times Monday into next week, as the Ontario high pressure system weakens and low pressure approaches the region from the Central Plains. Wood && .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