180 FXUS63 KGRR 110446 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 1246 AM EDT Sun Oct 11 2026 .KEY MESSAGES... - Rain Mid-Week then Cooler && .DISCUSSION... Issued at 232 PM EDT Sat Oct 10 2026 - Rain Mid-Week then Cooler Tropical moisture will graze southeast Lower Michigan tonight with low chance POPs there, then fair and warm weather expected into Monday before a shortwave trough rides over the top of upper ridging across the SE CONUS with a low pressure center tracking across the central Great Lakes on Tuesday. This is followed by a full latitude upper trough developing across the eastern CONUS by next weekend and the potential for a stronger low on Wed-Thu although ensemble spread remains considerable on the details. At this point it seems possible rain will be around for Wednesday and Thursday with sharply cooler weather for Friday and beyond. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 1245 AM EDT Sun Oct 11 2026 The remnants of Isaias will move through the Mid Atlantic and moist flow from it should drop cigs to IFR at JXN, LAN, AZO and BTL after 10Z. The TAF sites that will see the worst conditions will be JXN and potentially LAN. AZO should see IFR this morning, before improving early afternoon. Low cigs will continue through most of the day at JXN and LAN. Expect improving conditions after 22Z. GRR should see MVFR cigs but is far north enough to be outside the thickest low clouds. LLWS is expected through the first few hours of this TAF cycle but the LLJ will move to the east after 07Z. The only TAF site that should see rain is JXN, however there is a low probability chance for VCSH at BTL and LAN. && .MARINE... Issued at 232 PM EDT Sat Oct 10 2026 No changes to the Small Craft Advisory. Winds are still below 20 knots south of Pentwater but should be increasing this evening. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 5 AM EDT Sunday for LMZ846>849. && $$ DISCUSSION...Ostuno AVIATION...Ceru MARINE...Ostuno

NWS GRR Office Area Forecast Discussion