Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
887 FXUS63 KMKX 021552 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 1052 AM CDT Wed Jul 2 2025 .KEY MESSAGES... - There are small chances for thunderstorms this afternoon and evening. - There are chances for thunderstorms Thursday afternoon and night. Gusty winds may occur with any stronger storms. - Very warm and humid conditions for Independence Day and Saturday, with heat index values in the middle to upper 90s. - There are small chances for thunderstorms in the morning on Independence Day, with better chances Saturday into Saturday night, perhaps lingering into Sunday. Locally heavy rainfall is possible. && .UPDATE... Issued 1050 AM CDT Wed Jul 2 2025 Still seeing small chances (15-25%) for some isolated / widely scattered thunderstorms building into the region from the north this afternoon and evening. Earliest possible development for this activity would be 4 PM CDT this afternoon, though some models delay it to as late as 7 to 8 PM. After sunset, storm potential and coverage should begin to decline (if applicable to begin with). Sheppard && .SHORT TERM... Issued 426 AM CDT Wed Jul 2 2025 Today through Thursday night: Another warm and humid day is expected today, with modest westerly winds. There will be some diurnal cumulus clouds this afternoon. Highs in the middle 80s are expected for most of the area. The lake breeze should be negated by the westerly winds. There are small chances (around 20 percent) for showers and storms this afternoon and evening, as a frontal boundary sags southwest into north central to northeast Wisconsin and a modest 500 mb shortwave trough crosses the region. The upward vertical motion is rather weak, despite forecast soundings being uncapped by later this afternoon. Thus, CAMs are not showing much activity until perhaps this evening in northern parts of the area. Uncertain with if any development will occur and may remain isolated at best into this evening. There may be a few showers that clip western parts of the area later tonight, with the low level jet nose to the west generating some showers or storms. The warm front should move steadily northward into the area Thursday and Thursday evening, before pushing northward later Thursday night or early Friday morning. The low level jet remains focused more over west central and far southwest Wisconsin Thursday, before shifting its focus into northern Wisconsin Thursday night. The lake breeze boundary may provide another boundary source. Overall, there is uncertainty again with if and how much shower and storm activity occurs. Forecast soundings are uncapped again with peak heating, so a little more confidence that there may be at least isolated to perhaps scattered activity with the front. For now, kept 20 to 30 percent chances for Thursday afternoon and night. Gusty winds may occur with any stronger storms, with mean layer CAPE of 1000 to 1500 J/kg and deep layer bulk shear of 25 to 30 knots. Highs in the middle to upper 80s are forecast for Thursday, with heat index values in the upper 80s to lower 90s inland. Wood && .LONG TERM... Issued 426 AM CDT Wed Jul 2 2025 Independence Day through Tuesday: There may be a few lingering showers or storms that move northeast out of northern parts of the area early Friday morning, with the departing warm front. South to southwest winds in the warm sector on Independence Day into Friday night are expected, capping off the airmass. Thus, removed the rest of the lingering PoPs for Independence Day into Friday evening, and may need to remove PoPs into Saturday morning as well in later forecasts. Very warm and humid conditions will be the main story on Independence Day, with highs around 90 degrees and heat index values in the middle to upper 90s. South winds near the lakeshore may keep those areas cooler. This warmth will continue into Saturday, with highs in the upper 80s to lower 90s, highest southeast including Milwaukee. Similar heat index values in the middle to upper 90s are expected everywhere, with southwest winds expected Saturday. Confidence is fairly high, as models and ensembles have been pretty consistent with showing this warmth for many forecast cycles now. Continued to bring in higher PoPs (40 to 60 percent) later Saturday into Saturday night, as the cold front moves into the region, with low pressure passing by to the north. There is some uncertainty if this frontal passage may be a little slower and linger into Sunday. Either way, it looks to be a good amount of showers with some thunderstorms at times. Forecast soundings are showing more moist adiabatic lapse rates and potential for locally heavy rainfall, as bulk shear vectors may be more parallel to the front. High pressure may bring a brief period of quiet weather with somewhat cooler temperatures by Monday or Monday night, before more active weather moves toward the region by the middle of next week. Thus, this period may have some breaks in precipitation. Wood && .AVIATION... Issued 1050 AM CDT Wed Jul 2 2025 Dry weather and VFR expected through the remainder of the morning and early afternoon hours. Some slight potential (15-25%) for isolated to widely scattered thunderstorms to develop overhead (or push in from the north) as early as 4 PM CDT this afternoon, or as late as 7-8 PM CDT. Storm potential and coverage should decrease (if applicable to begin with) within a few hours after sunset this evening. Currently a few altocumulus (8,000 ft AGL) and cirrus (over 25,000 ft) clouds visible on satellite and surface observations. Expecting some scattered diurnal cumulus clouds to develop over the next hour or two around 5,000 ft AGL. If any thunderstorms were to develop, we would expect the cumulonimbus bases to be around the same altitude (5 or 6 thousand feet) later this afternoon and evening. Sheppard && .MARINE... Issued 426 AM CDT Wed Jul 2 2025 High pressure around 30.0 inches will linger across the Middle Mississippi River Valley today into Thursday, before moving to the east by Friday. Light southwest to west winds will continue today into tonight. Light north to northeast winds Thursday into Thursday night will shift south to southwest on Friday, as a warm front moves north through the region. South to southwest winds will then increase Friday night into Saturday night, as low pressure around 29.6 inches moves across Lake Superior and Ontario and pulls a cold front through the region. There will be mainly small chances for showers and thunderstorms at times this afternoon and evening. More widespread chances for showers and thunderstorms are expected later Saturday into Sunday, as the cold front crosses the lake. 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