910 FXUS63 KGRR 050604 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 104 AM EST Thu Nov 5 2026 .KEY MESSAGES... - Rain Continues into Thursday; Lakeshore Rain Chances Friday - Cooler Temperatures Settle in Through The Weekend && .DISCUSSION... Issued at 139 PM EST Wed Nov 4 2026 - Rain Continues into Thursday; Lakeshore Showers Possible Friday The surface low bringing showers and mild temperatures to the region today will move across the U.P. into Ontario Thursday. As it does so, a cold front will move through the region this evening with a narrow band of showers and perhaps a few rumbles of thunder that will precede a drop in temperatures for the area. Upper troughing moves in later tonight into Thursday providing synoptic forcing over Lake Michigan. Low level trajectories in the 925-700mb layer will be SW to WSW Thursday morning into the afternoon and the layer will be saturated. RRFS Bufkit soundings over Lake Michigan indicate lake induced CAPE values of 200-300 J/kg and plenty of low level moisture available. Lake enhanced showers should get going overnight and continue into Thursday afternoon under a SW flow regime. This will bring a fresh 0.10"-0.25" of rain Thursday mainly for areas near and north of a South Haven to Ionia to Alma line. The highest amounts will likely be across Muskegon, Newaygo, Ottawa, and Kent Counties. A secondary, and more powerful, cold front moves in Thursday night with 850mb temperatures falling to around -4C by Friday. This occurs via a deeper upper low diving south into the Great Lakes. Low level flows shifts N/NNW during the day Friday. Shallower moisture is shown Friday but still present in the 925-850mb layer. Either a dominant band or a few broken bands of lake effect rain showers in N/NNW flow should hug the lakeshore counties during the day with periodic wet weather, but with some dry periods as well. Just depends on how the band or bands meander during the day along the coast or just offshore. Additional areas such as near and north of US 10 and near/east of US 127 may also see some lake enhanced or lake effect rain showers off far northern Lake Michigan or via lake aggregate troughing occurring over Lake Huron. - Cooler Temperatures Settle in Through The Weekend Temperatures more reflective of early November are set to move in. As mentioned, 850mb temperatures bottom out around -4C Friday and this will yield highs in the mid to upper 40s. Combined with 10-20 mph winds, wind chill readings in the upper 30s to low 40s are forecast. It will feel more like November for sure. Highs Saturday into Sunday are forecast to be in the low to mid 50s, pretty typical for early November. && .AVIATION /06Z TAFS THROUGH 06Z FRIDAY/... Issued at 1252 AM EST Thu Nov 5 2026 The main concern throughout the 06Z TAF period is the continuation of MVFR ceilings and periodic light showers. Lake-enhanced rain showers have developed at most terminals overnight, but the most frequent showers are impacting GRR and MKG. This is expected to persist through the morning and into the afternoon. Early this evening, a cold front will switch winds from the southwest to the northwest, and may briefly reduce coverage of showers near the end of the period due to the more northerly wind direction. However, this may not completely end showers at terminals closer to the lakeshore, particularly at GRR/MKG/AZO/BTL. Ceilings are expected to remain MVFR, and may dip briefly to IFR at times, with periodic visibility reductions due to rain. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 7 PM EST this evening for LMZ844>849. && $$ DISCUSSION...Hoving AVIATION...BRC

NWS GRR Office Area Forecast Discussion