textproduct: Marquette

KEY MESSAGES

- Winter Weather Advisories remain in effect for the western and eastern UP through today for 3-6 inches of lake effect snow (locally up to 10 inches).

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

DISCUSSION

Issued at 417 AM EST Wed Dec 31 2025

Synoptic analysis early this morning shows low pressure system retrograding toward the Hudson Bay as a ridge of high pressure overspreads the Upper Mississippi Valley. This will keep Upper Michigan in a NW flow lake effect snow pattern through this evening. Therefore, Winter Weather Advisories remain in effect through Wed 18Z for the west and through Thu 00Z across the eastern counties of Alger, Schoolcraft, and Luce. While snowfall totals remain still marginal for the west in the 2-4" range, the eastern counties look more favorable for persistent lake effect banding through this evening per latest CAMS. This matches well with a surge of -20 to - 25C delta-T values from surface to 850 mb. So, snowfall amounts in the 3 to 6 inch range with localized amounts up to 9 inches can be expected across the east through this evening.

In addition to the snow, the main focus will be the frigid temperatures for tonight into New Year's day. 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 tonight 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 tomorrow, west to northwest flow LES looks to kick up again late tomorrow 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 /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 628 AM EST Wed Dec 31 2025

Northwesterly winds and lake effect snow showers persist at all terminals for much of today. This will bring mainly MVFR conditions to IWD and SAW, while IFR visibility has been more common at CMX this morning. This should improve to MVFR this afternoon. If steadier snow showers can pivot over SAW later this morning, then a brief period of IFR visibility will be possible there as well. Then, expect a gradual improvement to VFR at IWD and SAW this evening into tonight while MVFR prevails at CMX.

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 until 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.