719 FXUS63 KGRR 252319 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 719 PM EDT Sun Oct 25 2026 .KEY MESSAGES... - Cooler To Start The Week - Warming Into Midweek With Showers Possible - Widespread Rain Returns This Weekend && .DISCUSSION... Issued at 202 PM EDT Sun Oct 25 2026 - Cooler To Start The Week Mid-level water vapor imagery continues to show ridging across the central Great Lakes region today which is keeping fair conditions across the region. Surface observations upstream show a cold front forecast to drift across the region overnight. Frontal passage is favored to be dry, with just clouds across southwest Michigan. Can`t rule out light showers across Central Lower Michigan though probabilistic guidance keeps chances less than 15 percent. These clouds will lower the fog threat across the area, which is well reflected in NBM and REFS probabilistic guidance. Post frontal highs Monday and Tuesday will be in the low to mid sixties for most. - Warming Into Midweek With Showers Possible Southerly flow behind a warm front arrives late Tuesday bringing warmer conditons mid-week. Highs are favored to rebound to near seventy which is notably above average (which is the upper fifties this time of year). Decent signal exists in guidance for showers and maybe isolated thunderstorms given weak elevated instability between late Wednesday and late Thursday. - Widespread Rain Returns This Weekend A shortwave associated with the arrival of the more active subtropical jet marks the beginning of more widespread rain chances this weekend. Some question of whether rain impacts Halloween (PoPs around 40 percent as of present) or holds off until late Saturday/early Sunday. Rain continues into Sunday as well. Ensemble guidance has a mean of around 0.5 inches, with 90th percentile (high end) amounts of 1.5-2 inches possible in spots. So overall soaking rain is expected this upcoming weekend into early next week. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 717 PM EDT Sun Oct 25 2026 A cold front, currently over northern Lower, will sink south tonight. Expect some MVFR fog/cigs after 09z as the front moves through. Otherwise, VFR conditions will return by late morning/early afternoon as high pressure noses into the region. && .MARINE... Issued at 202 PM EDT Sun Oct 25 2026 Short range model guidance continues to show a burst of winds to around 20 knots behind a cold front overnight into Monday near Big and Little Sable points. The north-northeast flow looks to keep waves below criteria, and winds look to be just below as well based on the latest BUFKIT overviews. So will hold off at this time on an advisory, but a slightly more onshore direction would potentially bring 3-5 ft waves around the points. Next chance for hazardous winds and waves then arrives Wednesday as southwest winds increase ahead of a cold front. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ DISCUSSION...Thomas AVIATION...04 MARINE...Thomas

NWS GRR Office Area Forecast Discussion