869 FXUS63 KGRR 312346 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 746 PM EDT Tue Mar 31 2026 .KEY MESSAGES... - Severe chances through this evening - Light freezing rain possible early Thursday - Additional storm chances Thursday and Saturday && .DISCUSSION... Issued at 303 PM EDT Tue Mar 31 2026 - Severe chances through this evening Still keeping an eye on a line of storms just working into the northern part of the county warning area this afternoon. This line will slowly work south and east over the next few hours. Winds and hail continue to be the main threats for this afternoon and evening - with the threat being mostly over by 8-9pm or so for west Michigan. - Light freezing rain possible early Thursday Big weather maker works through the western Great Lakes Region late Wednesday with southern lower Michigan remaining mainly in the warm sector Wednesday night into Thursday. Recent model trends have been pulling this low track a little further to the northwest with the colder air having a harder time getting into central Michigan. This would keep the greatest impacts in Wisconsin and the Upper Peninsula with an overall decreasing trend in potential for freezing rain in the CWA compared to yesterday. Some light ice accumulation may still occur in our far northern counties...especially the slightly higher terrain in Osceola and Clare Counties and maybe even eastern Lake County...so that will have to be watched for a potential winter weather advisory for late Wednesday night into early Thursday. Would expect brief impacts mainly between 4am and 11am Thursday if ice materializes before temperatures warm through the day. - Additional storm chances Thursday and Saturday Active pattern continues into the weekend - with additional chances for storms Thursday and Saturday. Some severe weather possibilities exist for both days with Saturday starting to look like a potentially greater risk than late Thursday. Storms aside - there will be a decent amount of rain this week between today and Saturday. This should result in some rises on area rivers and potentially some minor flooding in trouble spots late this weekend into early next week. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 745 PM EDT Tue Mar 31 2026 The boundary has shifted south so the thunderstorm threat has all but ended. There is a slight chance that a weak line moving eastward from the Lake could cause a brief storm. So for that, have left a Prob30 in AZO for the next few hours. Otherwise, the plethora of moisture has allowed for reductions in vsbys and low cigs across the region. GRR, MKG BTL and LAN all have periods of IFR. That will continue through most of the evening. The northerly flow will bring some colder, drier air so there is a chance that cigs increase to above 1KFT. However, the drop in winds around 06Z could allow these cigs to cool and condense with IFR between 09Z and 14Z. CIGS will improve mid to late tomorrow morning, improving to MVFR between 14Z and 18Z and then to VFR afterward. There is still some evidence that the LLJ is aloft so have left LLWS for the next few hours as the southern TAF sites. && .MARINE... Issued at 302 AM EDT Tue Mar 31 2026 Hazardous winds and waves for small craft are expected much of this week. The current SCA goes through 12Z Wednesday. There will be a possible lull on Wednesday. Winds and waves will pick up again Wednesday night and persist into the weekend, && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory until 8 AM EDT Wednesday for LMZ844>849. && $$ DISCUSSION...Maczko AVIATION...Ceru MARINE...Ostuno

NWS GRR Office Area Forecast Discussion