860 FXUS63 KGRR 012300 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 700 PM EDT Wed Apr 1 2026 .KEY MESSAGES... - Threat for Freezing Rain Thursday Morning - Chance for Severe Weather Thursday Afternoon/Night - Another Round of Strong Storms Possible on Saturday && .DISCUSSION... Issued at 318 PM EDT Wed Apr 1 2026 - Threat for Freezing Rain Thursday Morning Precipitation moves in from southwest to northeast between 2 AM and daybreak Thursday. Forecast wet bulb temperatures in the relatively higher terrain of interior Central Michigan favor freezing rain at the onset of precipitation, before temperatures warm later in the morning. With perhaps slightly cooler wet bulb temperatures expected than previously, the 12Z HREF FRAM and freezing rain QPF from ECMWF, GFS, and Canadian models have trended a little south, with a higher potential for a quarter inch of ice in the high points of Osceola and Clare counties. Have expanded the winter weather advisory for the counties adjacent to Osceola and Clare to account for these trends. The window for freezing rain is fairly short but precipitation will be moderate and winds will be breezy. Impacts are more iffy south and west of Osceola/Clare, but bridges and overpasses could be affected briefly during morning travel. If ice accretion is indeed efficient in Osceola and Clare, some power outages could occur. - Chance for Severe Weather Thursday Afternoon/Night Temperatures and moisture increase substantially near and south of I-96 mid to late afternoon Thursday with a northward moving warm front. Thunderstorms around mid day are possible but will be well elevated and unlikely to be severe. More surface-based convection is then possible in Southwest Michigan during the evening. This high-shear low-CAPE setup offers some risk of damaging wind gusts, and even a tornado given ample low-level moisture and curved 0-1 and 0-3 km hodographs. Hail threat is low as most of the CAPE will be concentrated in warmer air at lower altitudes. - Another Round of Strong Storms Possible on Saturday (Issued at 400 AM EDT Wed Apr 1 2026) Another low will move through the area on Saturday associated with a stronger upper trough. Wind fields with this system are even stronger aloft with a 60kt low level jet and a 70kt mid level jet. The question is how much instability we will have before the cold front sweeps east during the day. If the timing of the front slows up just a bit it will place a portion of our area in the warm sector at max heating. We will be watching this time frame closely for another round of potential severe weather. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 700 PM EDT Wed Apr 1 2026 VFR breakout has finally occurred. Expect VFR cigs and vsbys this evening until the warm from moves to the north. MVFR will move overspread the region after 05Z with IFR cigs and vsbys by 07Z. The cold air is still on track to move from the north and bring a slight chance for freezing rain overnight, primarily between 06Z to 13Z at MKG and GRR. For that have PROB30s. MVFR will work north with both ceilings and visibilities trending down with rain. IFR is becoming more likely after 11z tomorrow. Low level wind shear will become a concern early tomorrow afternoon. While winds will remain gusty upwards of 25 to 30kts from the east at the surface, the Jet around 2KFT will be from the south/southwest upwards of 45 to 50kts. Expect winds to shift to the south around 20Z with the jet shifting to the southwest. The warm air and strong low level jet should allow for storms tomorrow afternoon. Not sure on track but storms will be possible after 18Z. Have put PROB30 groups for now to account for potential TSRA. Some of the strongest storms could become severe with damaging winds possible. Storms for all TAF sites could continue past 00Z Friday. && .MARINE... Issued at 318 PM EDT Wed Apr 1 2026 Beginning another small craft advisory with east winds strengthening late this evening, gusting at the shore 20-30 knots overnight into Thursday morning. Winds veer more south by Thursday evening, building larger waves in the nearshore, and scattered thunderstorms over Lake Michigan are likely. Gale force wind gusts are possible Thursday evening, especially in and around thunderstorms. && .HYDROLOGY... Issued at 318 PM EDT Wed Apr 1 2026 Two main additional rounds of rain are expected over the next few days. This should add 1-2 inches of rain to most areas, especially over the Muskegon River basin and western/lower Grand River basin. Thankfully, water levels have largely recovered from the last rainy weather pattern a few weeks ago, but this will get water levels rising again. Currently, the most vulnerable locations to potentially reach minor flood levels over the coming days are along the Muskegon River (primarily in Newaygo and Bridgeton), and along the Maple River in Maple Rapids (tributary to the Grand River). However, any shifts north or south of the upcoming heavy rain axis will change these results. Now is the time for people along West Michigan rivers to pay extra attention and have a plan to respond if water levels rise unexpectedly. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Winter Weather Advisory from 2 AM to 10 AM EDT Thursday for MIZ038-044>046. Winter Weather Advisory from 2 AM to noon EDT Thursday for MIZ039-040. MARINE...Small Craft Advisory until 8 AM EDT Friday for LMZ844>849. && $$ DISCUSSION...Duke/CAS AVIATION...Ceru MARINE...CAS HYDROLOGY...AMD

NWS GRR Office Area Forecast Discussion