534 FXUS63 KGRR 260800 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 300 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 rainby by 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 /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1139 PM EST Thu Dec 25 2025 Ceilings will lower to MVFR then IFR as freezing rain moves in from 9 to 12Z from west to east. Around 12-15Z areas along and south of a MKG to GRR to BTL line could start to see a transition to rain before ending 16-20Z across the area. Ice accumulations of a light glaze to a 0.10 are expected along and south of a MKG to GRR to BTL line with 0.10 to 0.20 isolated higher amounts north of that line. Ceilings will likely hover around 500 feet during the late morning into Friday evening. Expect southeast winds with gusts 20 to 25 knots overnight into Friday morning then becoming light and variable as the low moves overhead during the afternoon. Behind the low winds will be light and from the north to northwest. GRR Airport DSS Update: No changes to the airport briefing information provided Thursday afternoon. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Winter Weather Advisory from 5 AM early this morning to 4 PM EST this afternoon for MIZ037>040-043>046-050>052-056>059- 065>067-073-074. Winter Weather Advisory from 5 AM to 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...RAH

NWS GRR Office Area Forecast Discussion