185 FXUS63 KGRR 261145 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 645 AM EST Fri Dec 26 2025 .KEY MESSAGES... - Slippery travel today - Saturday night/Sunday rain - Colder Sunday night/snow && .DISCUSSION... Issued at 300 AM EST Fri Dec 26 2025 - Slippery travel today Regional and local radar shows light rain moving over the lake toward the cwa. Surface temperatures are aoa freezing southwest of a Holland to Battle Creek line; aob freezing north of there. A quick look at road temperatures indicates temperatures at 32 or above south of I-96 and below freezing north of there. Dewpoint depressions are around 7 degrees, suggesting that surface temperatures could fall a degree or two once the precipitation commences, which should be within the the next few hours. Isentropic lift looks moderately strong ahead of the surface low which is in northern Missouri which suggests that the precipitation will saturate the column quickly and freezing rain will develop prior to sunrise...in line with the going forecast. The far southwest cwa will see the least icing during this event, given the warmer surface temperatures and the northeast cwa will see the most. Still looking at a tenth of an inch of ice northeast of a Muskegon to Jackson line and perhaps two tenths of an inch northeast of a Stanton to Alma line; this will be the area that warms the slowest. Southwest of a South Haven to Marshall line, perhaps a trace to 0.04 inches of ice are expected. Winds are expected to decrease a bit as the low moves by which should mitigate power outage potential somewhat. However scattered power outages are still possible. Forecast soundings from the convection allowing models show a couple hundred j/kg MUCAPE over the far southwest cwa; it`s possible a thunderstorm or two could develop this morning/early afternoon. The precipitation will end from west to east this afternoon leading to dry weather tonight and Saturday. - Saturday night/Sunday rain An upper ridge axis will move over the Great Lakes Saturday and Sunday. H8 temperatures will climb to +10c and high temperatures Saturday will range from the mid 30s to lower 40s and Sunday from the lower 40s to mid 50s. A lee side low developing in the Plains will move east toward the state late Saturday. Light rain will develop Saturday night and continue into Sunday. Total rainfall from this system will range from a third of an inch near US-10 to an inch south of I-94 - Colder Sunday night/snow Once the low moves east late Sunday, much colder air will flow into the state behind it. Any lingering synoptic precipitation will turn to snow as h8 temperatures fall from +8c Sunday night to -14c by Monday afternoon. The associated upper low will cross the cwa Monday and both synoptic snow and lake effect snow will be in play; some accumulations are likely. Another shot of colder air will move through Tuesday night and Wednesday behind a clipper and more lake effect snow is possible. High temperatures from Tuesday through the rest of next week will be in the 20s. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 635 AM EST Fri Dec 26 2025 Light freezing rain and rain has developed across southwest Lower. Surface temperatures are right around freezing. TAFs were started with freezing rain where temperatures were 32F. We`ll see slow warming this morning with all terminals above freezing later this morning. Nephanalysis shows IFR/LIFR conditions to the west where cigs are around 400 ft and vsbys are aob 1sm br. These conditions will move over the terminals later this morning. Limited improvement can be expected after 00z; visibilities will rise, but cigs will remain below 1k ft. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Winter Weather Advisory until 4 PM EST this afternoon for MIZ037>040-043>046-050>052-056>059-065>067-073-074. Winter Weather Advisory until 11 AM EST this morning for MIZ064- 071-072. MARINE...Small Craft Advisory until 11 AM EST this morning for LMZ844>849. && $$ DISCUSSION...04 AVIATION...04

NWS GRR Office Area Forecast Discussion