FXUS63 KGRR 042353 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 753 PM EDT Mon May 4 2026 .KEY MESSAGES... - Marginal Risk Severe Tonight - Frost/Freeze Potential Tuesday and Wednesday Nights && .DISCUSSION... Issued at 258 PM EDT Mon May 4 2026 - Marginal Risk Severe Tonight Cold front sags south to meet modest moisture return overnight with some isolated storms capable of producing hail and enough DCAPE thanks to dry subcloud layer for strong gusty winds to reach the surface with any descending precip cores. Severe threat diminishes late tonight as the front clears the southern zones. - Frost/Freeze Potential Tuesday and Wednesday Nights Cold airmass behind the front with cloudy cool and showery conditions lingering across the southern zones on Tuesday. SOme clearing is possible across the north Tuesday night which would allow frost and freezing conditions, so Frost/Freeze headlines will probably be needed across the northern counties. Wednesday night could see more clearing and thus colder temperatures. A clipper type low moves through Thursday and model soundings show wet-bulb zero heights not far off the surface across the northern zones, so graupel or wet snow is possible there. Frost/Freeze potential lingers into next weekend and beyond as a cold northwest flow regime continues. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 753 PM EDT Mon May 4 2026 Scattered thunderstorm cells ongoing near AZO, BTL, and JXN over the next several hours will contain hail surface and aloft, and may produce microbursts and LLWS. Over Lake Michigan approaching MKG and GRR, scattered showers and thunderstorms (with occasional lightning) may also produce gusty winds in their vicinity as they move east toward LAN later this evening. Light rain showers are expected Tuesday morning with some MVFR ceilings in southern Michigan. && .MARINE... Issued at 258 PM EDT Mon May 4 2026 No changes to the SCA. Winds and waves will diminish behind the cold front late tonight and on Tuesday. Fairly tranquil conditions through Wednesday. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 11 PM EDT this evening for LMZ844>849. && $$ DISCUSSION...Ostuno AVIATION...CAS MARINE...Ostuno