Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
050 FXUS63 KMKX 072014 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 314 PM CDT Sat Jun 7 2025 .KEY MESSAGES... - A small chance (5-15%) for a stray shower this afternoon and evening, mainly in central and far-southern Wisconsin. - A broken line of showers and thunderstorms (60-85% chances) expected along a cold front on Sunday, which crosses the region west to east from 10 AM to 5 PM. A strong storm or two remains possible. - Additional shower and thunderstorm chances (45-80%) late Monday morning through Monday afternoon. A strong storm or two remains possible. && .SHORT TERM... Issued 315 PM CDT Sat Jun 7 2025 Tonight through Sunday night: With surface dewpoints in the mid 40s to low 50s, the dry mixed layer is likely to shield the area from precip for the remainder of this afternoon / evening (only 5 to 15% chance for a stray shower). For Sunday, the cold front passage will create a roughly 10 AM to 5 PM window for a broken line of storms (passing west to east), yielding 60-85% precip chances. A strong storm or two remains possible, particularly further south in Wisconsin (deeper into the warm sector). Deep layer wind shear is plentiful along the front (35 to 50 KT ahead of and along the boundary, more than that as time progresses), we primarily lack instability (which topped out in the 500-750 j/kg range for HREF SBCAPE Ensemble Mean). Exactly how much instability we have to work with will depend on the thickness and arrival time of antecedent cloud cover, as well as the arrival of the front itself (which is still under dispute from one model to the next). Additional ~30% chances for showers and storms linger behind the frontal passage, but mostly dry weather is expected Sunday evening and onwards. Sheppard && .LONG TERM... Issued 315 PM CDT Sat Jun 7 2025 Monday through Saturday: The large upper level low will move overhead on Monday, with the core of the colder air aloft moving through during the mid day and afternoon hours. This will result in widespread showers and a few tunderstorms during the afternoon hours. Shallow CAPE located below the -10C level will likely limit the thunderstorm coverage, though at least a few rumbles are possible. Dry air below the convective layer will pose a risk for gusty winds with any of the stronger storms. This activity will be very diurnally driven, and should rapidly end during the early evening, with clearing skies overnight Monday night into Tuesday morning. Remnant cyclonic flow on Tuesday may result in a few sprinkles or light showers during the afternoon, mainly across central Wisconsin. Most places should remain dry, however. A weak frontal boundary will settle into central Wisconsin on Wednesday, which will then serve as a focus for showers and thunderstorms Wednesday night and Thursday. That front will return north as a warm front late in the workweek, setting the stage for a fairly active end of the week/weekend as several weak shortwaves undercut a building upper level ridge. This pattern is suggestive of daily 30-40% chances for showers and thunderstorms, with the greatest coverage during the afternoon hours. Temperatures during this stretch look to be around or perhaps a touch above average. Boxell && .AVIATION... Issued 315 PM CDT Sat Jun 7 2025 Occasional broken VFR ceilings between 8 and 25 kft through the rest of today and overnight, with only a 5 to 15% chance of a stray shower (mainly in far-southern and central WI). Light southeast to east winds, turning due south overnight into early Sunday morning. Haze from wildfire smoke may reduce visibility to 6 SM at times (still VFR for the most part). Winds turn southwest and accelerate slightly (with a few gusts to 20 KT) Sunday morning ahead of the approaching cold front, which crosses west to east from roughly 10 AM to 4 PM CDT Sunday. A light west / northwest wind is expected behind the front. A broken line of showers and thunderstorms is likely (60-85% chances) along the front, with 30% chances for stray showers / weaker storms lingering behind the front. A strong storm or two will be possible during the frontal passage. Additional wildfire smoke may advect in behind the front leading to a thin haze as well. Cumulonimbus cloud bases are likely to remain VFR through this event for the leading edge storms, though any training storms could pose a brief window of MVFR ceilings. Sheppard && .MARINE... Issued 315 PM CDT Sat Jun 7 2025 High pressure of 30.0 inches over the Great Lakes region will continue east through this weekend in advance of an approaching low. Winds will remain light and variable today, becoming southerly and increasing a little as the low approaches Sunday. Broad low pressure of 29.5 inches will then gradually move eastward from the Northern Plains through the Great Lakes Region Sunday and Monday. Showers and storms are expected Sunday afternoon and evening as a cold front crosses the lake. Winds veer southwest and decelerate behind it. Additional chances for showers and storms on Monday, with modest southwest to west winds. 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