textproduct: Marquette

KEY MESSAGES

- A mix of freezing rain, sleet and snow is expected tonight into Friday. Mainly snow is expected in the Keweenaw and far east transitioning to sleet and/or freezing rain progressing towards the MI/WI border. Winter Weather Advisories are in effect for all of Upper Michigan as post holiday travel impacts are expected.

- A Gale Warning is in effect for eastern and central Lake Superior tonight into Friday. More gales are likely (70-80% chance) Sunday into Monday.

- Temperatures will average above normal through Sunday, then become sharply colder with lake effect snow into early next week.

DISCUSSION

Issued at 401 AM EST Thu Dec 25 2025

Early Christmas morning GOES water vapor imagery and RAP analysis show a deep mid level trough along the west coast with a ridge building into the Plains. Another broad trough is analyzed over eastern Canada. A surface high pressure is now descending southeast from the Canadian Prairie to northern Ontario and the Upper Great Lakes in the wake of a weak surface trough and cold front. The cold northerly flow set up will bring temps down into the upper teens to mid 20s this morning before they rise to near normal for the holiday with highs today in the 20s to low 30s. Besides a few morning flurries in the north central thanks to upslope flow, dry weather will hold until the next disturbance arrives.

Tonight through Friday, a shortwave will move from the northern Plains across the Upper Great Lakes bringing a wintry mix of freezing rain, sleet and snow to the UP. While discrepancies regarding where the axes of best moisture and warm nose aloft still are present in the current model suite, confidence in impacts due to sleet/freezing rain has increased. Highest snowfall amounts are expected over the northwest, focused on Keweenaw and Luce counties where 3-6" of snow are expected. There is a 25% chance for 7-8" in those areas; the solution if the aforementioned uncertain features shift south. Snow transitions over to sleet and/or freezing rain progressing southwest toward Wisconsin. Generally 1-2" of snow is expected outside those two counties. Freezing rain amounts up to 0.1" are expected, highest over Gogebic County, but also along the WI/MI state line and particularly higher again near the city of Menominee. Opted to hoist widespread Winter Weather Advisories for post holiday travel impacts.

Precip diminishes from west to east on Friday as the wave departs and weak high pressure tries to build in. With the warming airmass, sleet/freezing rain may mix in where previously primarily snow is expected tonight in the northeast. Temps peak in the upper 20s to mid 30s, coldest east. A lull in system PoPs is expected Friday night through Saturday, however low level saturation from southerly flow off Lake Michigan with the aid of upslope flow could result in freezing drizzle or periods of light freezing rain.

A stronger system is poised to develop later in the weekend as a more potent trough moves out of the northern Rockies, spinning up a deep surface low in the vicinity of southern Lower Michigan that then lifts into southern Quebec by Monday. This will likely bring a return of windy conditions and a lake effect snow regime for northwest wind snowbelts, especially across the eastern UP by early next week. This system will also usher in a return of much colder temps as deep longwave troughing over Hudson Bay becomes the dominant synoptic feature through much of next week. Look for highs more commonly in the teens to low 20s, with lows flirting with sub- zero again in the interior west as we approach the new year.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 640 AM EST Thu Dec 25 2025

The TAF period will start out with IFR and MVFR cigs as lake effect clouds continue to come off Lake Superior. A period of VFR conditions are expected this evening as winds become southerly and lake effect clouds diminish/push offshore. Thereafter a low pressure will move through the area bringing MVFR/IFR cigs/vis into the area as snow, sleet and freezing rain develop late this evening and continue into Friday morning. LIFR vis is expected at CMX by early morning where precipitation will predominately be snow. A mix of snow, sleet and freezing rain can be expected at SAW with predominately freezing rain at IWD. A period of LLWS is also expected overnight at IWD as a strong low level jet develops.

MARINE

Issued at 401 AM EST Thu Dec 25 2025

Northeast winds of 20-30 kts early this morning veer east by this afternoon, then southeast for tonight as a high pressure transits over northern Ontario. Winds then increase to gales of 35-40 kts over the north central and east. Southerly winds over the east half of the lake gradually fall below 20 kts on Friday while winds over the west half become westerly, remaining less than 15 kts. A period of southerly winds lakewide is expected Saturday and Saturday night, strongest winds Saturday afternoon and evening between 20-30 kts over the east. Another round of gales is looking increasingly likely late Sunday into Monday as a strong surface low develops in the vicinity of Lower Michigan and lifts northeast into Quebec. This will lead to high confidence (70-80%) in northwesterly gales on the back side of the system, with a 40-60% chance of storm force gusts of 50+ kt as well as increasing potential for heavy freezing spray. Mariners will want to continue to pay close attention to the forecast given the potential for hazardous conditions on Lake Superior later this weekend into the beginning of next week.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Winter Weather Advisory from 4 PM this afternoon to 1 PM EST Friday for MIZ001.

Winter Weather Advisory from 7 PM EST /6 PM CST/ this evening to 1 PM EST /noon CST/ Friday for MIZ002>005-009>011-084.

Winter Weather Advisory from 7 PM EST /6 PM CST/ this evening to 4 PM EST /3 PM CST/ Friday for MIZ006-012>014-085.

Winter Weather Advisory from 7 PM this evening to 7 PM EST Friday for MIZ007.

Lake Superior... Gale Warning from 1 AM to 1 PM EST Friday for LSZ244-245-264- 266-267.

Lake Michigan... None.