Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
219 FXUS63 KMKX 051930 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 230 PM CDT Thu Jun 5 2025 .KEY MESSAGES... - An Air Quality Advisory is in effect until noon Friday along the Lake Michigan shoreline due to wildfire smoke. - Mainly dry weather is likely through Friday, with a return of shower and storm chances Saturday afternoon into Monday. - Temperatures will remain within a few degrees of normal through early next week. && .SHORT TERM... Issued 227 PM CDT Thu Jun 5 2025 Tonight through Friday night: CAMs with near surface smoke concentrations continue to depict clearing conditions into this evening allowing us a short reprieve in air quality. However, additional smoke is expected tonight into tomorrow morning amid broad high pressure over the Upper Great Lakes and sinking air over eastern Lake Michigan. This smoke will be advected back toward our shoreline by east and northeast winds. Models depict this additional smoke finally mixing out Friday afternoon. An Air Quality Advisory will remain in effect along the Lake Michigan shoreline until Noon Friday as a result. Otherwise, high clouds will generally increase overnight as a weak 500mb wave approaches from Nebraska and Iowa. Shower activity is anticipated to move toward southwest and central Wisconsin during the morning hours on Friday but largely fizzle out as the high pressure remains in place and keeps dry air near the surface. Scattered sprinkles/light rain may occur over central WI, but most of this activity is expected to be virga. Small wiggles in the 500mb flow aloft will then continue through the day, causing nebulous areas of lift/shower activity into Friday night, but again, dry low levels will inhibit much of this from reaching the ground. Clouds continue Saturday, with a more amplified shortwave expected to move through during the afternoon. 12Z NAM soundings depict a bit of CAPE being realized and 12Z GFS soundings show a bit more saturation close to the surface, so this afternoon round on Saturday may overcome the dry low levels and provide light, scattered rain into the early evening. Highs will be in the mid to upper 70s inland Friday, with cooler temperatures by the lake, owing to east-northeast wind continuing off of the waters, with similar highs on Saturday CMiller && .LONG TERM... Issued 227 PM CDT Thu Jun 5 2025 Saturday through Thursday: The shortwave that will move through on Satuday is expected to cause weak surface cyclogenesis over Lower Michigan and Lake Huron through Sunday. On its heels, a cold front is expected to pass over southern Wisconsin during the afternoon hours on Sunday bringing good chances for rain (60 to 80% PoPs). The timing of this front is a bit early, with models depicting it crossing the Mississippi River Valley in the late morning. As a result, sufficient values of SBCAPE for stronger storms (>500 J/kg) do not build ahead of the front and instead we`ll likely see nothing more than some scattered rumbles of thunder along the front during the afternoon. This cold front should then clear the area east by the late afternoon and early evening. It should be noted that the timing of the frontal passage has varied from run to run lending a bit of uncertainty. A slower frontal passage would support more CAPE in the afternoon, and thus, stronger storms. Trends will be monitored heading into Sunday. There will be a brief lull Sunday night, before an upper trough gets kicked out of Canada and into the Upper Great Lakes by the afformentioned surface cyclogenesis that will occur over Michigan. As a result, chances for showers and a few rumbles of thunder (30 to 60%) will then move through the area on Monday, with thunder more likely during the afternoon. One last gasp of scattered light rain may occur Tuesday as a weak trough moves through before high pressure returns by mid next week. Overall, temperatures will stay within a few degrees of normal through the weekend given the cloud cover, rain, and east winds off of the lake. Temperatures should begin to rebound by the middle of next week as ridging builds over the plains. CMiller && .AVIATION... Issued 235 PM CDT Thu Jun 5 2025 FU and HZ will linger along the lakeshore through tonight, while areas inland should see better vis. High clouds will move in aloft and BKN to OVC VFR will linger into tomorrow. Areas of rain will try to move in, but be largely hampered by lingering dry air near the surface, leading to virga. Winds will remain light and easterly to northeasterly. CMiller && .MARINE... Issued 227 PM CDT Thu Jun 5 2025 High pressure will linger over the Upper Great Lakes through Saturday, causing persistent light north to northeasterly winds. Winds will come around to southeasterly on Sunday ahead of a cold front, with moderate southwest winds expected by Monday. Showers and storms may occur along the front on Sunday. CMiller && .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