584 FXUS63 KGRR 291037 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 637 AM EDT Wed Jul 29 2026 .KEY MESSAGES... - Next chance for rain Friday and Saturday && .DISCUSSION... Issued at 141 AM EDT Wed Jul 29 2026 Quiet weather through Thursday under high pressure with the next chance for rain coming on Friday into the weekend. A shortwave trough rounds the top of the western CONUS ridge and closes off across or just south of the Great Lakes. An associated surface low meandering across the Ohio Valley brings a moist easterly flow into Lower Michigan where mid level f-gen forcing and instability should bring rain and embedded thunderstorms with some diurnal enhancement on Saturday. Afternoon showers could linger into Sunday and even Monday before the upper low gets kicked out. && .AVIATION /12Z TAFS THROUGH 12Z THURSDAY/... Issued at 637 AM EDT Wed Jul 29 2026 VFR conditions will continue through Wednesday night. Northwest winds AOB 10 knots today, except for some gusts to near 20 knots possible at MKG this afternoon. && .MARINE... Issued at 129 AM EDT Wed Jul 29 2026 Winds and waves are diminishing and are or soon will be below 4 feet in all zones, so the SCA/BHS are expired. Waves could increase to 3 to 4 feet again at South Haven on Wednesday afternoon as north winds increase to near 20 knots. Thursday to Saturday should see fairly light winds and waves with north winds increasing again on Sunday to near 20 knots. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ DISCUSSION...Ostuno AVIATION...Ostuno MARINE...Ostuno

NWS GRR Office Area Forecast Discussion