904 FXUS63 KGRR 061204 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 704 AM EST Tue Jan 6 2026 .KEY MESSAGES... - Mixture of precipitation expected today - Warmer with rain Thursday and Friday - Colder with chances for snow this weekend && .DISCUSSION... Issued at 339 AM EST Tue Jan 6 2026 - Mixture of precipitation expected today A mid level shortwave can be seen in water vapor imagery zipping east across Iowa early this morning. This wave will be the driver for mixed precipitation across Southwest Lower Michigan today. Surface low pressure has formed and is situated near the Iowa/Illinois border as of 08z. The mid level wave and its surface low will move through the forecast area today, with the surface low sliding east across Southern Lower Michigan near I-94. Precipitation will be driven by the left exit region of a 140 knot upper jet that will result in a warm air advection response in low levels. The resultant isentropic lift is quite strong this morning which will be focused by a warm front. Surface temperatures will be a few degrees either side of the freezing mark this morning as the precipitation develops. We are expecting rain in the south near I-94 for the most part. A brief mix can be expected near I-96 but impacts will be limited as temperatures warm to above freezing around or shortly after daybreak. The Winter Weather Advisory look in great shape (no changes with this forecast) as this is where the temperatures are expected to be slightly below freezing (32F) at the onset of precip (roughly north of a Pentwater to Newaygo to Howard City to Alma line). The below 32F air quickly contracts further this morning to our northeast counties, which is the climatological locations that see freezing precipitation the longest given its our furthest north area and highest ground/elevation. The area to see freezing precipitation the longest will be across Osceola, Clare, Mecosta and Isabella counties. So, the bottom line is rain will spread into areas in the south early this morning it will be a mix north of I-96 where snow and freezing rain are expected. Freezing rain totals of a trace to a tenth of an inch are expected across Central Lower Michigan. The precipitation will tail off this afternoon and end as a mix of rain and snow. - Warmer with rain Thursday and Friday Our upper pattern shifts to a warmer southwest flow on Thursday and Friday. Surface low pressure will lift through the area during this time frame and be a focus for heavier rainfall. Rainfall amounts look to be on the order of a half inch to an inch. PWAT values will rise toward 0.90 which is well above the 90 percentile for this week. What snowpack remains will certainly melt off during the latter half of the work week. The warmest day of the week looks to be Thursday with highs rising to around 50 along I-94, the middle 40s along I-96 and the low 40s up near U.S. 10. We are not expecting any hydro/flooding issues given a limited snowpack and generally less than an inch of rain. Within bank rises on area rivers will certainly occur. - Colder with chances for snow this weekend Colder air briefly settles in for Saturday into Sunday as an upper trough digs across the Great Lakes region. A low associated with the upper trough will move through as well and bring a mix of rain and snow initially that will change to all snow as we head into Saturday night and Sunday. The snow does not look heavy at this time. Highs on Sunday will be in the upper 20s to around 30. && .AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/... Issued at 704 AM EST Tue Jan 6 2026 Aviation conditions are in the process of deteriorating this morning as rain and lowering ceilings move in. Poor aviation conditions are expected throughout the 12z to 12z TAF period. IFR conditions should prevail area wide by 16z with even lower conditions projected as we move through the afternoon and into tonight. LIFR ceilings will be prevalent tonight. The poor conditions are being driven by a low pressure system moving through the region today followed by surface high pressure tonight which will hold low level moisture in place. Winds will back from easterly to the north and then west this afternoon as low pressure moves east. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Winter Weather Advisory until 1 PM EST this afternoon for MIZ037>040-043>046-051-052. MARINE...None. && $$ DISCUSSION...Duke AVIATION...Duke

NWS GRR Office Area Forecast Discussion