textproduct: Marquette

KEY MESSAGES

- Lake effect snow continues through tomorrow. So, Winter Weather Advisories remain in effect for snow amounts of 6 to 8 inches and potential visibility reductions from blowing snow across the Keweenaw with the addition of Ontonagon, southern Houghton, and Baraga Counties. Higher terrain could see upwards of 8 inches.

- Lake effect snow will impact Alger, Northern Schoolcraft, and Luce Counties. So, a Winter Weather Advisory has been issued through tomorrow for 6 to 8 inches with localized higher amounts. Wind gusts up to 35 mph will result in whiteout conditions at times.

- Coldest air of the season and since January, 2019, will create a period of below zero temperatures from Thursday night through at least Saturday morning across most of Upper Michigan. Temperatures below -15F and wind chills near -40F are likely. An Extreme Cold Warning has been issued for Thursday night/Friday morning across western and central Upper Michigan. And, an Extreme Cold Watch remains in effect for those areas as well through Saturday morning.

- A Cold Weather Advisory has been issued across the eastern third of Upper Michigan for Thursday night/Friday morning where wind chill values will reach -25 to -20 degrees.

DISCUSSION

Issued at 428 PM EST Wed Jan 21 2026

Vis satellite imagery/RAP analysis this afternoon still has Upper Michigan under the influence of a broad trough and its embedded weak waves in the mid-level flow. Meanwhile, surface high pressure remains concentrated over the Southeast U.S. and Southern Plains. This pattern has been conducive to persistent lake effect snow and the coldest air mass of the year and since January, 2019, for the U.P.

So far today, ground-based obs across the area are reporting widespread temperatures in the mid to upper teens with some light snow showers. A deepening trough over northern Minnesota this afternoon will deepen, though, by the time it reaches Upper Michigan this evening. This along with a frigid air mass will help to reinvigorate lake effect snow over both the Keweenaw/west UP as well as the eastern portions of the forecast area through tomorrow. Therefore, the current Winter Weather Advisory across the Keweenaw has now been extended through Thursday evening, and Ontonagon, southern Houghton, and Baraga Counties have been added to it. Farther east, a Winter Weather Advisory has also been issued for Alger, northern Schoolcraft, and Luce Counties early tonight through Thursday evening. In addition, bumped snowfall totals up a bit into the 6 to 8 inch range for both advisories with localized higher amounts, especially across the higher terrain along the spine of the Keweenaw where CAMS are highlighting an intense band this evening. Advisory expiration times may have to be re-visited and possibly extended if the cold air mass supports lake effect snow further into Friday. With that, focus turns to the main impact of the forecast period. And, that is the dangerously frigid air mass progged for Thursday through the weekend.

As 850 mb temperatures drastically fall to near -30 degrees by Friday morning and combine with wind gusts in the 30 to 35 mph range, wind chill values will reach the -40 to -35 degree mark across western and central Upper Michigan. Therefore, an Extreme Cold Warning has been issued from Thursday night through Friday morning as confidence increases to above 90%. Simultaneously, this will put the eastern third of the U.P. close to -25 degree wind chills. Thus, a Cold Weather Advisory was also issued for those counties. And, a Cold Weather Watch will likely be needed for the eastern third as well for Friday night/Saturday morning with the next forecast issuance. What this equates to in overnight low temperatures without the wind factor is -18 to -15 degrees across the warned area for Friday morning and even colder for Saturday morning with -25 to -20 degree temperatures. As a result, warnings and advisories will likely be issued for Friday night/Saturday morning as well with future forecast issuances. With very gradual warming through the weekend and into next week, some of these warning/advisory threats may diminish. Nonetheless, high temperatures will struggle to get out of the single digits above zero for most of the forecast area through the beginning of next week. And, overnight lows will consistently drop into the single digits below zero through the extended period.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 629 PM EST Wed Jan 21 2026

Behind a passing disturbance, an uptick in lake effect snow is expected in the NW wind snowbelts (CMX and IWD) through the TAF period. This is already occuring at CMX where IFR/LIFR vis has been reported for the last several hours. Snow showers will fill in at IWD tonight bringing IFR cigs/vis. Further east, occasional light snow showers are possible at SAW but VFR/MVFR conditions are expected with no significant drops in visibility expected.

MARINE

Issued at 428 PM EST Wed Jan 21 2026

High wind event returns tonight and lasts through Saturday morning. Widespread northwest winds of 25 to 35 knots are expected along with heavy freezing spray for the duration of the event. Best chances for gales of 35 knots will be Thursday into Friday morning across the central and eastern portions of the lake. Meanwhile, the heavy freezing spray will impact the entire lake for the same time period due to the strength of the cold air mass. Winds finally weaken below 20 kts across the western half of the lake on Friday night followed by the remainder of the lake on Saturday morning. Winds will then stay below 20 knots until Sunday with a gradual uptick above 25 knots starting Sunday night.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Winter Weather Advisory until 7 PM EST Friday for MIZ001>004- 084.

Extreme Cold Warning from 10 PM EST /9 PM CST/ Thursday to 1 PM EST /noon CST/ Friday for MIZ001>005-009>012-084.

Extreme Cold Watch from Friday afternoon through Saturday afternoon for MIZ001>005-009>012-084.

Winter Weather Advisory from 10 PM this evening to 7 PM EST Thursday for MIZ006-007-085.

Cold Weather Advisory from 10 PM Thursday to 1 PM EST Friday for MIZ006-007-013-014-085.

Lake Superior... Heavy Freezing Spray Warning from 1 AM EST /midnight CST/ Thursday to 1 PM EST /noon CST/ Friday for LSZ162.

Heavy Freezing Spray Warning until 7 PM EST /6 PM CST/ Friday for LSZ240>242-263.

Heavy Freezing Spray Warning until 1 AM EST Saturday for LSZ243-244-264.

Heavy Freezing Spray Warning from 1 AM Thursday to 1 AM EST Saturday for LSZ245>248-265.

Heavy Freezing Spray Warning from 1 AM Thursday to 7 AM EST Saturday for LSZ249>251-266-267.

Gale Warning from 7 AM Thursday to 1 PM EST Friday for LSZ265>267.

Lake Michigan... None.