061 FXUS63 KGRR 261104 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 704 AM EDT Sun Jul 26 2026 .KEY MESSAGES... - Northwest flow regime with occasional chances for rain but low confidence in convective details && .DISCUSSION... Issued at 211 AM EDT Sun Jul 26 2026 - Northwest flow regime with occasional chances for rain but low confidence in convective details The Great Lakes region remains in between an upper high across the western CONUS and longwave troughing across the eastern CONUS with occasional shortwave troughs passing through and bringing the chance for some much-needed rain. A weakening shortwave trough moving through early this morning has yet to initiate any showers, which is not surprising given limited moisture and lift. Isolated showers are possible through the afternoon. Still low confidence in the details of how things play out tonight through MOnday night in terms of organized convection, but instability and shear are sufficient for a slow-moving front and weak midlevel vorticity max to focus convection across Minnesota and into Wisconsin this afternoon which eventually moves southeast across Lake Michigan and perhaps western Lower Michigan. The hi-res convective allowing models take the bulk of the storms west of our forecast area, but there is a chance an MCS could impinge on the western or southwest zones late tonight or early Monday morning. Additional convection is possible across the rest of the forecast area during Monday and Monday night as the front pushes south. The front moves through by Tuesday with fair weather for mid to late week before the longwave upper trough amplifies with a cold front bringing another chance of rain by next weekend. && .AVIATION /12Z TAFS THROUGH 12Z MONDAY/... Issued at 704 AM EDT Sun Jul 26 2026 Patchy IFR/MVFR conditions with low stratus this morning should go over to VFR by 18Z. There could be some rain moving in tonight across western Lower Michigan, with MKG having the best chance late tonight. Winds will be from the southwest AOB 10 knots. && .MARINE... Issued at 211 AM EDT Sun Jul 26 2026 Today should see a continuation of southwest winds around 10 to 15 knots then thunderstorms could bring strong wind gusts over Lake Michigan tonight. A cold front moves through Monday night and north winds increase to near 30 knots with waves building over 4 feet on Tuesday and continuing into Wednesday. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ DISCUSSION...Ostuno AVIATION...Ostuno MARINE...Ostuno

NWS GRR Office Area Forecast Discussion