textproduct: Grand Rapids

KEY MESSAGES

- Gradually Improving Conditions Today

- Significant Lakeshore Snow Possible Wednesday Morning

- Episodic Lake Effect Snow Wednesday into Friday

- Rare and Potentially Near Record-Setting Cold This Weekend

DISCUSSION

Issued at 316 AM EST Tue Jan 20 2026

- Gradually Improving Conditions Today

Current plan is to expire the Winter Storm Warning scheduled at 7 AM. Water vapor imagery indicates an approaching subtle upper PV lobe that will likely reinvigorate LES a bit just prior to the expiration time. The GRR WSR-88D VWP suggests inversion heights still a respectable 6 kft AGL near the leading edge of the lake plume. Visibilities at the lakeshore are well above a mile at this time, but could see them dropping briefly as inversion heights get a slight boost. Surface observations show the leading edge of the lake modified plume just west of a South Bend to Kalamazoo line. Flow is already quite confluent along this boundary and there could be an FGEN-aided uptick in snow intensity for this particular region in the next couple hours; if this overperforms, we might have to consider a local extension of the warning. Farther inland, had considered cancelling the winter weather advisory early, but we are just now starting to some more organization and inland penetration of LES bands compared to just a couple hours ago so travel hazards will likely persist a bit longer even away from the lake.

Regardless of the details, the overarching theme is that travel this morning will not be fun, given slippery conditions in temperatures that are cold enough to be largely impervious to conventional road treatments. Conditions should gradually improve during the day however.

- Significant Lakeshore Snow Possible Wednesday Morning

Models have been consistent showing an Alberta Clipper approaching the western Great Lakes and inducing surface cyclogenesis over south-central Lake Michigan. Not only will there be isentropic ascent with this, but it also appears that FGEN will become quite strong along the pre-existing land/lake baroclinic zone. As noted previously, there is sensitivity to how the surface low sets up, but it is quite plausible that lakeshore areas of Muskegon... Ottawa...and perhaps Oceana Counties could see intense snowfall prior to and during the Wednesday morning commute and totals in excess of 6 inches are not out of the question. This is a headline-worthy scenario, but would like to clean the slate of current headlines first so this will likely become a day shift decision point.

- Episodic Lake Effect Snow Wednesday into Friday

This period will be characterized by deep cyclonic flow with the polar jet displaced to the south and a trend towards increasingly cold 850 mb temperatures. Some model guidance also suggests that Wednesday night could even feature significant inland penetration of a dominant LES band in favorable laminar flow. Unfortunately, the overarching theme of challenging travel conditions will continue.

- Rare and Potentially Near Record-Setting Cold This Weekend

We still anticipate a powerful arctic front to pass through Thursday night with manifestly colder temperatures beginning Friday. Highs in the single digits are looking increasingly likely Friday and Saturday. Minimum temperatures will be especially impressive thanks to calm conditions with high pressure centered over the area and a fresh snowpack. This could be a case where cold weather advisories are warranted based on temperature alone.

Below normal temperatures are expected to continue into next work week.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1233 PM EST Tue Jan 20 2026

Radar shows light snow showers continuing across the region. Boundary layer temperatures will warm a bit ahead of the next low pressure system that will arrive tonight, but likely not quite enough to end the snow showers.

Synoptic snow will arrive after 06z tonight and visibilities will fall to around a mile by 12z. Some improvement in visibilities are anticipated after 15z as the system moves away to the east.

GRR WATCHES/WARNINGS/ADVISORIES

MI...None. MARINE...Small Craft Advisory until 7 AM EST Wednesday for LMZ844>849.