textproduct: Duluth

KEY MESSAGES

- Colder temperatures move in this afternoon into tonight with light snow showers continuing for most locations through tonight. Additional snow accumulations will be 2 inches or less for most.

- Moderate to heavy snowfall is expected to occur along the South Shore today through Saturday, with heaviest accumulations in the higher elevations near the lake. A Winter Storm Warning is in effect for Iron, Bayfield, and Douglas Counties through Saturday.

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

- 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 226 PM CST Fri Jan 16 2026

Active weather conditions this afternoon across a large portion of the CWA as a cold front is currently sweeping through. On the synoptic scale, vertically-stacked low pressure is currently centered near Lake Superior and the Upper Peninsula of Michigan. Across a large portion of the CWA, including all of northeast Minnesota, the main story today is the rapidly falling temperatures following the cold frontal passage and lingering snow showers. For the MN side of the CWA, today's high temp is occurring right around now and temps are expected to plunge into the single digits tonight. Widespread light snow showers continue through the afternoon into tonight as widespread FGEN at 850mb and saturation around the DGZ continues. Additional snow accumulations for most of the area will be 2 inches or less with snow character forecast to be light and fluffy.

Of note is a small (20%) chance for snow squalls in northwest WI this afternoon as the cold front moves through. A band of strong FGEN at 925mb along the cold front combined with steep 3-6km lapse rates around 8 degC/km and higher negative omega could lead to locally strong snow squalls that could rapidly reduce visibility to 1/4 mile or less. While confidence in snow squalls isn't high, it will be something to monitor this afternoon.

Along the South Shore of Lake Superior, conditions are expected to be much more active this afternoon through Saturday as northwest winds behind the cold front bring CAA from an Arctic airmass. The hazards along the South Shore today through tomorrow will be coming in two forms: lake effect snow and gravity wave snow in the lee of the North Shore terrain ridge.

For the lake effect snow: Northwest winds following the cold fropa will bring rapidly decreasing temps this afternoon into tonight as an Arctic airmass settles over the CWA and Upper Midwest this weekend. 850mb temps will be decreasing to around -15 degC tonight, which is forecast to produce 150-300 J/kg of lake induced CAPE as lake sfc temps hover around 1-2 degC. While snowfall rates won't be particularly heavy, topping out at 0.5" per hour on Saturday morning, the prolonged duration of lake effect snow is expected to lead to heavy accumulations in northern Iron County around the Penokee Range between this afternoon and Saturday evening. Additional accumulations of 4 to 8 inches with locally higher amounts up to 11 inches are expected by Saturday evening. A Winter Storm Warning is in effect for Iron County, with a Winter Weather Advisory for Ashland County. Expect lake effect snow to diminish on Saturday night as northwest winds shift to the southwest ahead of an approaching Clipper.

For the gravity wave snow: Northwest winds produced an area of moderate snowfall in northern Douglas and Bayfield Counties earlier this morning, which has continued into the afternoon. Based on the current winds and shape of this snowfall, this is the result of a gravity wave occurring in the lee of the North Shore terrain ridge. The forcing associated with this gravity wave snowfall is well exemplified in the 1000-850mb omega from the RAP, which shows a strong area of sinking motion along the North Shore and lift on the western shore of the Bayfield Peninsula into northern Douglas County. This is progged to continue through tonight and much of Saturday as northwest winds continue and low-level saturation persists. Additional snowfall of 4 to 7 inches is expected in northern Douglas and Bayfield Counties, with highest amounts most likely in the higher elevations of Bayfield County where orographic enhancement will help elevate snow totals. A Winter Storm Warning has been issued for these counties due to this gravity wave snowfall.

As winds shift to the southwest on Saturday night, both the gravity wave snowfall and lake effect snow will come to an end. This wind shift is occurring ahead of an approaching Clipper, which is expected to move through the Upper Midwest on Sunday. This Clipper will be bringing another round of widespread light snow to the CWA, with snow totals likely to be in the 1-3" range with locally higher amounts to 4". Since temperatures are likely to be below the DGZ, snow character will likely be fine and light with elevated SLR of 20:1 or higher. This Clipper is currently on track to exit the area by Monday morning with lake effect snow likely lingering into early next week as cold northwest winds persist.

The main concern early next week will be very cold temperatures and wind chills well below zero. Low temps on Monday and Tuesday mornings will be in the negative teens for most locations. Breezy northwest winds on Monday morning are forecast to drop wind chills into the -30s across much of the CWA with isolated pockets of -40s possible in the Arrowhead. Cold Weather Advisories will likely be needed on Monday, which is expected to be the coldest morning in the forecast period in terms of wind chill. Looking ahead to next week, cold temps linger as an Arctic airmass remains over the north- central CONUS. Additional snow showers will be possible, notably late Tuesday into Wednesday. Given that temps will be very cold, accumulations will likely be on the light side.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 519 PM CST Fri Jan 16 2026

MVFR to IFR conditions across northeast Minnesota through tonight in stratus and scattered snow showers. IFR conditions will be more widespread across northwest Wisconsin with lake effect snow downstream of Lake Superior tonight into Saturday morning. Expect conditions to slowly improve through the day on Saturday across northeast Minnesota, with continued lake effect snow downstream of Lake Superior in northwest Wisconsin.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 226 PM CST Fri Jan 16 2026

A cold front is currently passing through this afternoon, with northwest winds increasing. Gusts of 25 to 30 knots are expected to develop and persist this afternoon through most of Saturday. Waves will build to around 4 to 6 feet along the South Shore as well. Small Craft Advisories remain in effect for all nearshore zones (except Chequamegon Bay). Downslope winds are likely to develop this evening into tonight along the North Shore, which could lead to brief and localized gales right next to the shoreline from Silver Bay to Grand Marais.

Winds briefly lessen Saturday night ahead of another clipper system. A stronger cold front should bring an additional round of strong winds with gales possible (50-60% chance) Sunday night through Monday morning. While gales may subside Monday morning, breezy conditions should prevail through Monday night, keeping conditions hazardous for small craft.

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 Saturday for WIZ001-002- 004. Winter Weather Advisory until 6 PM CST Saturday for WIZ003. MARINE...Small Craft Advisory until 8 PM CST Saturday for LSZ140. Small Craft Advisory until 4 PM CST Saturday for LSZ141>148- 150.