FXUS63 KGRB 050736 AFDGRB Area Forecast Discussion National Weather Service Green Bay WI 236 AM CDT Tue May 5 2026 Forecast discussion for routine morning forecast issuance .KEY MESSAGES... - Cooler temperatures are expected for the rest of the week, with overnight lows approaching freezing. There is a 30-80% chance for frost from central to east-central WI Tuesday and Wednesday nights (highest in central WI, lowest near the lakeshore). - Minor precip chances this week with little to no impacts. && .DISCUSSION... Issued at 236 AM CDT Tue May 5 2026 Surface cold front is southeast of the state now which will allow winds to subside overnight, and marks the start of a cooler pattern. The main impacts over the next few days will be frost/freeze potential during the nights. There are minor precip chances, but amounts and impacts will be minimal. Temperatures: Highs today will be about 15 to 20 cooler than Monday, in the upper 40s to middle 50s. Similar readings persist on Wednesday and Thursday, and then return closer to seasonal normals on Friday and this weekend, in the upper 50s and 60s. Overnight lows will be the numbers to watch, as temperatures approach freezing Tuesday night through Thursday night. This will likely warrant frost or freeze headlines for central and east- central WI (these products have not yet begun for northern WI). NBM probabilities show a 30-100% chance of reaching 36 degrees or cooler Tuesday and Wednesday nights, with the lowest probabilities in east-central WI near the lakeshore. Frost potential is less certain Thursday night, with probabilities of 5-60% in central and east-central WI. By the weekend, overnight lows look to stay warm enough to avoid frost where the growing season has started. Precip: A few precipitation opportunities throughout the week, but impacts from any precipitation will be minimal. Upper low will spin northward across Ontario and Hudson Bay the next couple days, which will keep northeast Wisconsin in northwest flow and send a few shortwaves through the area. Today's shortwave is likely to be dry, with only the HRRR showing a few spits of precip. NBM probabilities for 0.01" of rain are around 5%. Similar situation on Wednesday, with a 10-20% probability of measurable precip across northern WI. The potential is best on Thursday (20-40%) for some measurable rain, again not amounting to much more than a few hundredths. && .AVIATION...for 06Z TAF Issuance Issued at 1017 PM CDT Mon May 4 2026 Late this evening, strong cold advection is occurring behind the cold front. High based fair weather clouds continue to move into north-central WI with bases above 6 kft. A band of mid-level clouds is slowly shifting southeast over northeast WI. Winds continue to slowly subside and are generally gusting from 15 to 25 kts. For overnight, expectations are that winds will gradually subside to 10-15 kts. Conditions will remain VFR as the fair weather clouds shift across northern Wisconsin. Cloud bases will remain above 6 kft generally. After a period mostly clear skies early Tuesday morning, fair weather clouds will pop with daytime heating on Tuesday. Coverage will be highest north and west of the Fox Valley, but ceilings will likely be above 4.5 to 6 kft. West- northwest wind gusts to 20 kts can be expected on Tuesday afternoon before subsiding Tuesday evening. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION.....KLJ AVIATION.......MPC