textproduct: Duluth

KEY MESSAGES

- Scattered light snow continues for much of the Northland today, gradually ending from west to east later this morning and afternoon. Additional snow accumulations will be less than one inch for most locations.

- Moderate to heavy snowfall lingers along the South Shore through today, with heaviest accumulations in the higher elevations near the lake. A Winter Storm Warning is in effect for Iron, Bayfield, and Douglas Counties through this afternoon, with a Winter Weather Advisory for Ashland County.

- Very cold temperatures are expected this weekend through next week. Wind chills in the -30s to -40 are possible on Monday morning, which is expected to be the coldest morning until next weekend.

- There will be additional chances for light snowfall as a series of Clippers move through on Sunday and again on Tuesday night into Wednesday.

DISCUSSION

Issued at 354 AM CST Sat Jan 17 2026

Today:

Regional radar imagery and surface observations show persistent, scattered light snow showers across most of the Northland early this morning. These showers are being aided by some weak negative omega values (i.e. upward motion) associated with the backside of a low pressure system in the eastern U.P. of Michigan that will slowly be departing today. Therefore, expect these lighter snow showers and flurries to continue off and on today before gradually ending from west to east across NE MN later this morning and afternoon and in northwest Wisconsin this evening as drier air briefly moves over the area behind the departing low pressure and works to unsaturate the dendritic growth zone. Snow amounts remain light for most locations, with an additional dusting to around 1 inch of fluffy snow.

There will be an exception to the lighter snowfall amounts along the South Shore of Lake Superior due to gravity wave and lake effect snow impacts.

The South Shore lake effect snow will persist into this evening due to the colder airmass moving in, with lake induced instability of 150-350 J/kg as a result of 850 mb temperatures around -14 to -18 degC over a Lake Superior surface temperature of around +1 to 2 degC. Snowfall rates should generally top out around 0.5"/hr this morning and afternoon, but the extended duration of these rates should produce additional accumulations of 3-6" in northern Iron County due to terrain enhancements and an additional 1-3" in the remainder of Iron County and eastern Ashland County, and around 1 inch or less for western and southern Ashland County. Snow comes to an end late this evening as winds turn westerly and shifts the lake effect snow north of the South Shore. A Winter Storm Warning remains in effect for Iron County with a Winter Weather Advisory for Ashland County through this afternoon.

As for the gravity wave, high-resolution model guidance continues to point to sinking motion along the North Shore and frontogenesis/upward motion downwind of the North Shore terrain ridge into northern Douglas County and the Bayfield Peninsula due to northwest winds and lingering low-level moisture. This pattern is forecast to persist through the daytime hours today before waning this evening as drier air moves in from the northwest and winds shift westerly. Expect additional 2-4" of snow in northern Douglas and Bayfield Counties today due to the gravity wave and some terrain enhancements. Winter Storm Warnings remain in effect through this afternoon for Douglas and Bayfield Counties.

This snow will be accompanied by northwest winds throughout the day, with gusts to 15-25 mph for most locations.

Tonight - Monday:

Winds back to southwesterly tonight into early Sunday ahead of an approaching Clipper system that will be quickly moving across the Upper Midwest tonight into Sunday. There isn't a lot of moisture with this system, but the synoptic support for lift is actually quite good. The expectation is for a quick round of widespread lighter snow to move through with snow rates of less than 0.5"/hr. With a very cold airmass in place, most of the vertical temperature profile for this system will be colder than the dendritic growth zone, so snow should be a very light and finer consistency. Snow should come to an end for most locations Sunday evening aside from the South Shore. Widespread snow accumulations should range from 0.5-2" for most of the Northland, with the best potential for >1" along and south of the Iron Range (30-50% chance). As for the South Shore, very cold 850 mb temperatures of -20 to -25 degC could produce lake- induced instability values of 800-1000 J/kg, which is a large amount of instability for lake effect snow. Therefore, this area will be something to watch for several inches of snow accumulations for Sunday into Monday, particularly in northern Iron County due to both the lake and terrain enhancement could produce some locally heavier snowfall rates.

In addition to the snow, this system will bring strong northwest winds behind a passing cold front Sunday PM through early Monday morning. Wind gusts of 25-35 mph are expected for much of the Northland and the North Shore could reach 35-45 mph. There is a 20-40% chance that wind gusts on the North Shore could exceed 45 mph and a Wind Advisory may be needed.

These winds will also combine with very cold low temperatures dropping into the teens below zero Sunday night into Monday morning to produce wind chills of -25F to -40F across the Northland, coldest in northeast Minnesota. Cold Weather Advisories will likely be needed.

Next Week:

Cold, arctic air lingers over much of the region much of the upcoming week with single digit highs and lows in the single digits to teens below zero Tuesday through Friday. Each night and morning for Monday night, Wednesday night, and Thursday night could see wind chills dip to -15F to -30F. Even colder arctic air is in store for next weekend, with high temperatures possibly below zero for Saturday and Sunday (40-80% chances, highest in northeast Minnesota), lows in the teens to 20s below zero, and wind chills possibly dropping below -30F once again.

Additional snow showers will be possible at times next week, primarily late Tuesday into Wednesday. However, given limited moisture availability and the very cold temperatures, snow amounts should be lighter.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 546 AM CST Sat Jan 17 2026

MVFR conditions in stratus and scattered light snow showers through the morning, with more sporadic snow showers but MVFR ceilings persisting during the afternoon into evening, especially in northwest Wisconsin. Lake-effect snow downwind of Lake Superior should keep conditions MVFR to more IFR for the South Shore in northwest Wisconsin. Winds will be breezy out of the northwest today, then weaken briefly this evening and tonight as they back to southerly before increasing again on Sunday. An additional round of widespread light snow with a Clipper system expands into northeast Minnesota and northwest Wisconsin from the west starting late tonight and expanding into Sunday, with snow moving into BRD, INL, and possibly HIB towards the end of the current 12Z TAF period. Conditions across northeast Minnesota and northwest Wisconsin deteriorate to IFR or lower on Sunday with the snow after the end of the current TAF period.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 354 AM CST Sat Jan 17 2026

Northwest wind gusts of 25 to 30 knots persist into the afternoon today, and linger towards early evening for Grand Marais to Grand Portage before weakening tonight and backing to southwesterly. Waves of 4 to 6 feet expected along the South Shore. Small Craft Advisories remain in effect for all nearshore zones except Chequamegon Bay. Downslope winds along the North Shore could lead to brief and localized gales right next to the shoreline from Silver Bay to Grand Marais through about 9 AM CST this morning, as well.

A stronger cold front associated with a Clipper system will bring an additional round of strong winds with gales possible (50-80% chance) Sunday evening into Monday morning. A Gale Watch has been issued. While gales may subside Monday morning, strong winds persist through Monday into Monday night, keeping conditions hazardous for small craft. These strong winds combined with cold, arctic air will also pose a risk for potential heavy freezing spray along the South Shore Sunday evening into Monday morning.

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 Warning until 6 PM CST this evening for WIZ001- 002-004. Winter Weather Advisory until 6 PM CST this evening for WIZ003. MARINE...Small Craft Advisory until 8 PM CST this evening for LSZ140. Gale Watch from Sunday evening through late Sunday night for LSZ140>148-150. Small Craft Advisory until 4 PM CST this afternoon for LSZ141>148-150.