Little Switzerland Snow Report

072 FXUS63 KGRB 140641 AFDGRB Area Forecast Discussion National Weather Service Green Bay WI 141 AM CDT Fri Aug 14 2026 Forecast discussion for routine morning forecast issuance .KEY MESSAGES... - Scattered showers (30-55%) late tonight through Saturday afternoon. Latest trend is downward for rain chances and rain amounts on Saturday. - Another round of showers (30-50%) and a few thunderstorms (10-20%) Saturday night as cold front moves through. Locally heavy rain possible. - Drying out later Sunday into Monday with next chance for showers and some storms Tuesday into Wednesday. && .DISCUSSION... Issued at 140 AM CDT Fri Aug 14 2026 Day today, some showers arrive late tonight: Weak high pressure overhead with pockets of mid cloud and locally dense fog. Thus far the fog is variable in coverage to have anything more than SPS out, but will monitor to see if a Dense Fog Advisory is needed anywhere. A lull in cloud cover this morning, then clouds increase, thicken late today ahead of southern stream shortwave that arrives late tonight. Easterly winds result in warmest readings today central to north-central WI with highs in the lower, maybe mid 80s. Few showers make it into southern tier of counties very late tonight ahead of the wave. Showers/Storms Saturday and Saturday night: Trend that is emerging is most guidance (except especially the NAM) is to keep majority of widespread showers on Saturday to the south closer to the higher instability and convergence on nose of LLJ. This shows up nicely when looking at HREF 1hr probs of 0.01" which shows higher probabilities staying over far southern WI, northern IL during the morning. Increasing moisture and lift on the north edge of this could still produce scattered showers, with the greatest focus southern Fox Valley to the lakeshore. If this trend continues though, some locations could stay dry during the daytime on Saturday, which looked very unlikely a couple days ago. Main front does swing through on Saturday night with primary shortwave over Lake Superior. This is likely when most locations will see at least scattered showers. Given boundary is interacting with PWATs over 1.8" (95+ percentile) and slower MBE vectors are forecast, locally heavy rain may occur Saturday night. Dry later Sunday into Monday: Front clears eastern WI by Sunday morning. A few showers may linger during the morning, but mainly a dry day is expected. Looks kind of breezy with peak gusts over 20 mph at times as winds shift northwest. Despite being behind the front, it could actually be warmer on Sunday with more sunshine and mixing. Not as humid as Saturday, but dewpoints will still linger into the mid 60s over east-central most of the day. Monday will be noticeably less humid across the board. Next chance for rain is Tuesday...Northwest flow brings another shortwave trough and cold front through leading to next chance for organized showers and some thunder Tuesday. Greatest instability Tuesday afternoon remains southwest of our area, so risk for severe storms looks lower which aligns with various ML projections that shows greater signal southern MN into IA. Models/ensembles are picking up on another wave sliding in from the west interacting with the frontal boundary to keep showers and some storms lingering later Tuesday night into Wednesday. With PWATs up to 1.5 thrown into the mix, probabilities of 0.5 inch/1.0 inch of QPF have steadily increased over the last few runs. ECMWF EFI/SOT now has some signal for heavy rain. WPC is also now indicating a Marginal to Slight (level 1/2 of 4) for excessive rain during this time. As we saw with the evolution of this weekends higher risks that eventually shifted south, these areas can shift with time, but will be something to watch as we get closer to this time frame. Cooler air push behind this system for the end of the week with highs settling into the lower to middle 70s. && .AVIATION...for 06Z TAF Issuance Issued at 1041 PM CDT Thu Aug 13 2026 Patchy areas of fog are beginning to develop across parts of east- central WI late this evening. Periods of IFR vsbys are possible at GRB, ATW, and MTW, through about 10Z. Once the fog clears VFR conditions are expected for the rest of Friday. Light and variable winds are expected overnight. Friday easterly winds will increase gradually with gusts up to 15kts possible. Beyond the TAF period a round of scattered showers and isolated storms is expected to move into the region Saturday morning. Period reductions in visibility along with lightning are expected to be the main aviation impacts. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION.....JLA AVIATION.......GK