textproduct: Grand Rapids

KEY MESSAGES

- Heavy snow north of Grand Haven today/tonight

- Light snow south of I-96 tonight

- Light snow Wednesday, then cold

- Chance of snow next weekend

DISCUSSION

Issued at 316 AM EST Mon Dec 1 2025

- Heavy snow north of Grand Haven today/tonight

A winter storm warning is in effect from Ottawa county north this afternoon and tonight for the potential of heavy snow. An approaching upper trough will turn boundary layer winds to the southwest today. Coupled with deep moisture and h8 temperatures around -11c, an excellent setup for heavy lake effect snow is developing. Bufkit omega profiles indicate strong lift intersecting the dgz this afternoon and tonight. Using 850 mb omega fields as a proxy for lake band location, the prime target for heavy snow looks to be from Muskegon north into southern Oceana county this afternoon and moving north into southwest Mason county tonight. The potential for 6-12 inches of snow exists in Muskegon and Oceana counties and 4-8 inches in Mason county. We also issued a winter weather advisory for Lake, Newaygo, and Ottawa counties for 3-7 inches of snow. Highest amounts will occur in western Lake, western Newaygo, and northwest Ottawa counties.

Snowfall surrounding the advisory counties will be minimal...around an inch or so.

Once the trough axis comes through late tonight, the lake bands will break apart and try to reorient to the northwest-southeast. However, much drier air will be moving across the lake and lift will be waning due to differential anticyclonic vorticity advection (DAVA).

- Light snow south of I-96 tonight

The same trough that will be promulgating the heavy lake effect snow over the northwest lake shore tonight will also produce light synoptic snow south of I-96. An inch of snow is possible along the I-96 corridor and 1-2 inches along I-94 as the trough moves through. Compared to what we just had yesterday, this isn't much. However, 1-2 inches overnight ahead of the morning commute could make for some slippery travel, so keep that in mind as you plan your day Tuesday.

- Light snow Wednesday, then cold

A strong cold front will drop south from Canada Wednesday. Models show a band of light snow accompanying the front. QPF around a tenth of an inch will result in 1-3 inches of light snow. H8 temperatures drop from -5c Wednesday to -19c by Thursday morning setting the stage for a cold Thursday and Friday. Highs both days will only reach the lower to mid 20s, except along the lake shore where onshore winds may keep temperatures closer to 30.

The high (lake delta t/s in the mid 20s) instability over the lake won't be fully realized in the form of lake effect snow due to the very dry air moving in behind the front.

- Chance of snow next weekend

Another cold front/short wave combination will arrive Friday night. A 30-50 percent chance of light snow is anticipated with this system. Most of the ECMWF ensemble members produce snow, but not all and those that do only paint around a half inch. What the cold front will do, however, is keep highs well below normal in the mid 20s.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 552 AM EST Mon Dec 1 2025

Radar shows the first few echos developing over the southern part of the lake moving northeast. We'll lake effect snow continue to develop this morning and most likely become intense at times at MKG where several hours of IFR/MVFR conditions are expected.

Elsewhere, generally VFR conditions are expected today. However, tonight, light snow will develop and MVFR/IFR conditions will develop after 00z.

GRR WATCHES/WARNINGS/ADVISORIES

MI...Winter Storm Warning from noon today to 7 AM EST Tuesday for MIZ037-043-050. Winter Weather Advisory from noon today to 7 AM EST Tuesday for MIZ038-044-056. MARINE...None.