FXUS63 KGRB 081653 AFDGRB Area Forecast Discussion National Weather Service Green Bay WI 1153 AM CDT Wed Jul 8 2026 Updated aviation portion for 18Z TAF issuance .KEY MESSAGES... - There is a 15-30% chance of severe thunderstorms along with heavy rain possible this afternoon and evening, primarily across central and east-central Wisconsin. Damaging winds and localized flooding will be the main threats, but small hail and an isolated tornado are also possible. - Continue to monitor the potential for excessive heat early next week as high temperatures rise into the low to middle 90s on Monday and Tuesday. && .DISCUSSION... Issued at 122 AM CDT Wed Jul 8 2026 A complex of thunderstorms across Minnesota was working into northwest WI early this morning. There have been a few warnings with this complex so far. This complex is expected to move into north-central WI between 09z-12z and across far northeast WI after 12z. Several models continue to show convection developing south of the current cluster of storms towards 12z that could impact locations south of Highway 29. Previous forecast had pops, thus not much change in this area. Later this morning into the afternoon, several solutions to contend with that leave some questions in how widespread severe weather will be. This was seen in the Storm Prediction Center Day 1 Outlook that has shifted the Slight Risk (Level 2) is little further south. The latest HRRR would support the morning convection south of Highway 29 with another complex developing along and south of the Highway 29 corridor later this afternoon, between 2 pm and 4 pm west of the Fox Valley, and from 4 pm to 7 pm for Green Bay and the Fox Valley east to the lakeshore. Bufkit soundings indicated 1,000 to 2,000 J/KG of CAPE and 0-6 km shear values around 30 knots to support severe storms. Strong/damaging winds and heavy rainfall that could lead to localized flooding are the main risk. Small hail and an isolated tornado are also possible. Showers and scattered storms will continue tonight, ending across the north late. Showers and a few storms will continue across east-central WI through the night into Thursday. The chances of showers and storms continue into Thursday afternoon across central and east-central WI, although severe weather is not expected. Dry conditions expected this weekend into early next week. 500mb ridge building across the central United States early next week will bring well above normal temperatures along the potential for excessive heat and heat related impacts as high temperatures Monday and Tuesday will be in the upper 80s to middle 90s. && .AVIATION...for 18Z TAF Issuance Issued at 1153 AM CDT Wed Jul 8 2026 Late this morning, a cold front stretches from west-central Wisconsin to north-central Wisconsin. MVFR to IFR ceilings exist along and north of the front while VFR conditions prevail to the south and south of RHI. This front will provide the focus for clusters of showers and storms this afternoon and evening. Thunderstorm redevelopment is expected 19-20Z with impacts into RHI/AUW/CWA starting during this timeframe. These storms are expected to increase in coverage and proceed into the Fox Valley in the 22-23Z period. Strong storms are likely with gusts in excess of 40 mph possible with ceilings and visibilities falling to MVFR and IFR/LIFR respectively. After the initial push of storms, scattered showers with embedded thunder looking to continue through much of the evening, while light showers could persist across parts of central and east- central WI into Thu morning. Late tonight, there is a decent signal for ground fog to develop. Central and north-central WI have potential for sub-IFR visibilities. The fog should lift into a MVFR stratus deck after about 15Z. Winds will belight over the period. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION.....Eckberg AVIATION.......MPC