textproduct: Marquette

KEY MESSAGES

- Winter Weather Advisories in effect for the western and eastern UP through New Year's Eve for 3-6 inches of lake effect snow (locally up to 10 inches).

- Colder temperatures for New Year's Eve into New Year's Day with wind chills in the negative single digits and teens for the first hours of 2026.

DISCUSSION

Issued at 257 PM EST Tue Dec 30 2025

Early afternoon water vapor imagery and RAP analysis shows the wave responsible for our recent blizzard retrograding through Quebec, while ridging exists over the Pac NW/Canadian Rockies. NW flow locally between these features, disrupted by a weak wave now pushing into northern MN. Though there is good saturation within a deep DGZ ahead of this feature, the lift associated with it is rather weak and transient. So while many in the UP will see light snow this afternoon/evening, it is not expected to amount to much, outside of the NW flow lake effect belts.

In the wake of this system, a modest NW flow lake effect snow event will occur this evening into New Year's Eve (Wed). CAMs have been hinting at potential for a briefly enhanced convergence band pointing into northern Ontonagon/southern Houghton County this afternoon/evening, which is supported by the current surface wind observations (although difficult to find evidence in satellite or radar due to observing limitations). Though it should be mostly a marginal LES event for the west given modest inversion heights around 1.5 km, that potential did tip the scales for Winter Weather Advisory issuance, with a general 2-6" and locally up to 9" possible along the M-26 corridor SW of Houghton should that band materialize. In the east, better parameters exist late this evening into Wednesday (particularly Wednesday morning into Wednesday evening) as inversion heights rise to 2 km and surface to 850 mb delta-T values reach 20-25C. Advisories in effect here for 3-7" snow, locally up to 10" in the more persistent bands through Wednesday evening.

The other story will be the cold temperatures. A reinforcing shot of cold air arrives behind the weak disturbance, sending 850 mb temps down to the low -20s(C), -1 to -2 sigma. The cold air, combined with modest northwesterly winds around 10 kt gusting to 20 kt, will send wind chills into the -5 to -20F range late New Year's Eve into the early hours of 2026 (coldest west). While these values do not quite reach cold weather advisory criteria, they will be impactful given that they will occur coincident with outdoor New Year's festivities in some areas.

Looking ahead to the first few days of 2026, it will be a relatively stable pattern with the Quebec low becoming incredibly strong as it retrogrades into Hudson Bay, while ridging maintains over the northern Rockies, keeping us in northwest flow. After diminishing early on New Year's Day, west to northwest flow LES looks to kick up again late New Year's Day into the following night behind another weak disturbance, but due to the dry air, it is not likely to be particularly notable. Temps remain slightly below normal in the NW flow, but not excessively cold, and there are signs of moderation back to near normal for Sunday into early next week.

AVIATION /06Z TAFS THROUGH 06Z THURSDAY/

Issued at 1208 AM EST Wed Dec 31 2025

Northwesterly winds and lake effect snow showers will prevail for this TAF period. This will bring MVFR conditions, particularly to KIWD and KCMX. Some of the showers may (30% chance) bring KCMX to IFR. KSAW will be on the edge of the band of showers and will bounce around between MVFR and IFR.

MARINE

Issued at 257 PM EST Tue Dec 30 2025

Northwest winds and waves continue to gradually diminish today, but the lighter winds will be short lived as a reinforcing shot of cold air arrives behind a weak system tonight. This will result in a fairly long period of northwesterly gales of 35-40 knots Wednesday morning into at least Thursday evening. The frigid airmass will also result in heavy freezing spray for this period for most of the lake. Borderline gales to 30-35 kt will continue through the end of the week, and some parts of the eastern half of the lake may have to have gale and freezing spray warnings extended.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Winter Weather Advisory until 1 PM EST this afternoon for MIZ002-003.

Winter Weather Advisory until 7 PM EST this evening for MIZ006- 007-014-085.

Lake Superior... Heavy Freezing Spray Warning from 7 AM EST /6 AM CST/ this morning to 7 PM EST /6 PM CST/ Thursday for LSZ241>251- 263>267.

Gale Warning from 10 AM this morning to 7 PM EST Thursday for LSZ244>251-264>267.

Lake Michigan... None.