textproduct: Duluth

KEY MESSAGES

- Freezing fog tonight may create a glaze of ice accumulation on elevated surfaces.

- Next round of freezing drizzle chances are Saturday as the next weather system moves in.

- Heavy lake effect snow is forecast along the South Shore Sunday late afternoon into Monday morning.

- Sharply colder temperatures and strong winds arrive Sunday with wind chills dropping well below twenty degrees below zero by Sunday night with strong northwest winds.

DISCUSSION

Issued at 208 PM CST Fri Dec 26 2025

Overcast skies continue into tonight across the Northland. Freezing fog is forecast to form tonight and may create visibilities as low as 1/4 mile. These conditions will be monitored through tonight for any possible fog headline needs. While not expected widespread, areas of a glaze of ice coating cannot be ruled out from any more dense pockets of freezing fog tonight. As we move into Saturday, a new weather system will approach the Upper Midwest from the Northern U.S. Plains, pushing a surge of more moist air into our region. This will initially manifest as a mix of drizzle and freezing drizzle Saturday morning. While ice accumulations are generally expected to be a tenth of an inch or less, this will be enough to create very slick conditions on untreated roads and sidewalks.

By pre-dawn Sunday morning into Sunday mid-day, much colder air will begin to wrap into the Northland. This transition will turn the wintry mix over to all snow from west to east. Snowfall for northeast Minnesota will remain relatively light, generally a dusting to a few inches. Moderate to heavy snowfall is forecast though for northwest Wisconsin Sunday afternoon to Monday morning. As the north-northwesterly flow sets up Sunday evening night, lake effect snow bands are expected to ramp up significantly along the South Shore of Lake Superior. These bands are likely to produce heavy snow through Monday morning, particularly in Ashland and Iron counties where travel may become very difficult. Winter Storm Watches are now in effect for these two counties for the heavy snowfall expected Sunday afternoon to Monday morning. The rest of northwest Wisconsin is forecast for a general 3 to 6 inches of snowfall in this time period. Winter Weather Advisories are likely to be needed in time pending major forecast changes.

The next cool down period begins Sunday daytime as a much colder airmass drops into the region. Expect temperatures in northern Minnesota to decrease through the daytime Sunday. By Sunday night, actual air temperatures will fall below zero. The combination of cold and wind will produce dangerous wind chill values as low as 30 below zero at times through New Year's Day. The only reprieve will be a slight warm up on Tuesday back towards normal. Under these conditions, frostbite can occur on exposed skin in as little as 10 to 30 minutes.

AVIATION /00Z TAFS THROUGH 00Z SUNDAY/

Issued at 533 PM CST Fri Dec 26 2025

Flight categories are expected to remain poor across the region for the next 24 hours. IFR to LIFR conditions are likely at the terminals tonight due to low stratus and freezing fog. Visibilities may drop to 1/4 mile at times. Some improvement to MVFR is possible Saturday afternoon, but ceilings will remain stubborn. Winds will be light tonight, shifting to the southeast on Saturday and accelerating.

MARINE

Issued at 208 PM CST Fri Dec 26 2025

Quiet conditions are expected on Western Lake Superior through Saturday with southeast winds 10 to 15 knots and waves 2 feet or less. Conditions deteriorate rapidly Sunday. A Gale Watch is in effect from Sunday evening through Monday evening for all nearshore waters. Northwest winds of 20 to 30 knots with gusts up to 45 knots are possible, along with waves building to 4 to 8 feet. Additionally, a Heavy Freezing Spray Watch is in effect for the same period, as rapidly accumulating ice may pose a hazard to vessels. There is a 40 percent chance of Storm Force gusts north and east of Grand Marais Monday.

For the open water discussion, refer to the NWS Marquette Area Forecast Discussion at weather.gov/mqt.

DLH WATCHES/WARNINGS/ADVISORIES

MN...None. WI...Winter Storm Watch from Sunday afternoon through Monday morning for WIZ003-004. MARINE...Gale Watch from Sunday evening through Monday evening for LSZ121-140>148-150. Heavy Freezing Spray Watch from Sunday evening through Monday evening for LSZ140-141-145>148-150.