286 FXUS63 KGRR 150623 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 223 AM EDT Sun Mar 15 2026 .KEY MESSAGES... - Strong Spring Storm on Sunday - Winter Returns with Lake Effect Snow Monday into Tuesday && .DISCUSSION... Issued at 245 PM EDT Sat Mar 14 2026 - Strong Spring Storm on Sunday The Winter Storm Watch was replaced with a Winter Weather Advisory which will include all the counties in the Watch plus Isabella County. Slick roads are expected late this evening from a burst of snow followed by freezing rain on Sunday morning. A Wind Advisory is in effect from late Sunday morning across the I-94 corridor and the southeast forecast area from Jackson to Lansing. The expected forecast progression of potentially high-impact weather elements through Sunday is thus: bands of snow from warm advection/isentropic ascent and associated frontogenetic response will move north through the forecast area this evening with light accumulations of generally 1 to 3 inches across the northern half of the forecast area. The precip will change to sleet and freezing rain on Sunday morning and then rain by Sunday afternoon as continued mid level warm advection becomes surface based with the passage of the warm front. Winds in the warm sector will gust to advisory criteria of 45 mph at times across the southern and southeast forecast area during the afternoon and evening. A line of convection is expected to be across Lake Michigan Sunday evening which will move east and bring the potential for severe winds, although the threat may be limited by the expected diurnal decrease of instability in the warm sector. The threat of a QLCS tornado remains low, but not zero as shear profiles remain favorable for that type of convective mode through the evening. Heavy rain could cause some minor flooding issues, especially across the northwest zones. See the Hydrology Discussion section. - Winter Returns with Lake Effect Snow Monday into Tuesday An arctic front erases the warm sector Sunday night with rain changing to snow and lake effect snow intensifying through Monday as inversion heights are around 7 kft AGL into Monday night. We will probably need winter weather headlines for snow and blowing snow into Tuesday morning. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 223 AM EDT Sun Mar 15 2026 IFR with snow is occurring near LDM, RQB, and MOP early this morning. For MKG, GRR, and LAN, likely VFR early this morning with some very light snow reaching the ground (instead of evaporating below the cloud), and vertical temperature profiles support light ice pellets prior to dawn before precipitation takes a break. Gusty winds and LLWS will be a prevalent challenge today. Rain showers likely this evening with a chance of a thunderstorm. These could temporarily boost wind gusts or fluctuate the amount of LLWS either way. && .MARINE... Issued at 245 PM EDT Sat Mar 14 2026 A temporary lull in the winds and waves tonight before winds increase dramatically early Sunday. We issued a Gale Warning from Sunday morning into Monday evening for an extended period of strong winds which could include thunderstorms on Sunday evening and lake effect snow and freezing spray on Monday. && .HYDROLOGY... Issued at 245 PM EDT Sat Mar 14 2026 Rivers remain high after several recent rounds of heavy rain. While the upcoming Sunday/Monday storm looks to keep its heaviest rain north of our big watersheds, we are still expecting around 1.5 inches of rain north of I-96, including across much of the Muskegon River watershed. Current river modeling suggests this may be enough to generate some minor flood stage on the lower portions (below Croton Dam) of the Muskegon River in the midweek timeframe. Meanwhile, further south, the lower Grand River is already near bankfull, and just beginning to drop after recent high water. An expected one-half inch of rain coming up will prolong this high water, but is currently not expected to cause any new flooding. Nevertheless, surprises happen, and if the heavier axis of rain pivots south toward the Kent County area we could generate additional general flooding as well as eventual river flooding. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Winter Weather Advisory until 2 PM EDT this afternoon for MIZ037>040-043>046. Wind Advisory from 11 AM this morning to midnight EDT tonight for MIZ059-066-067-071>074. MARINE...Gale Warning from 8 AM this morning to 10 PM EDT Monday for LMZ844>849. && $$ DISCUSSION...Ostuno AVIATION...CAS MARINE...Ostuno HYDROLOGY...AMD

NWS GRR Office Area Forecast Discussion