textproduct: Duluth

KEY MESSAGES

- Light snow is expected tonight. Most places less than an inch, but up to 2-3 inches in northern Iron County.

- A cold and blustery Wednesday followed by below-zero low temperatures Wednesday night and Thursday morning. Wind chills as low as -20 to -25 are expected and localized -30 values are possible.

- Cold weather with intermittent light snow chances are expected for the next week.

DISCUSSION

Issued at 134 PM CST Tue Dec 2 2025

Southwesterly flow with warm air advection continues this afternoon ahead of a cold front that will pass through tonight. We've had some light fog and flurries with this air mass, and that is expected to transition more into light snow going into this afternoon and evening from northwest to southeast as the cold front quickly passes through. Not much has changed with this update as far as snowfall amounts; just a very tiny nudge upward in QPF and resultant snowfall amounts. There won't be much moisture to work with and the front will pass by so quickly that most places will pick up a dusting to around an inch. The best lift will be over the Arrowhead and into ~Iron County, so some locally higher amounts are possible there. Perhaps up to 2" around Grand Marais and to around 3" around Hurley (HREF probabilities are ~50% for 3" or more there).

Winds become blustery quickly following the cold front and plenty of much colder (and drier) air will move in from the northwest for Wednesday. For most places, Wednesday's highs will probably happen at midnight with temperatures roughly remaining steady in the single digits to teens above zero in the afternoon. There is some question about lingering snow showers in the post-cold frontal cold air advection regime. I kept some flurries through the night and into the morning, but ending after that. Several CAMs hint at some lake- effect snow bands forming off the larger lakes, and the instability will certainly be there for that with the cold air moving in. Dry air moving in may reduce chances for this along with ice cover increasing on these lakes. Some light accumulations downwind of the large lakes can't be ruled out, but it shouldn't be much. It will be these places where around an inch or perhaps very slightly higher amounts may be possible when all is said and done on Wednesday.

Attention then turns to the cold night expected Wednesday night into Thursday morning as high pressure passes by to our south and the coldest air settles over us. At this time, it's still looking like most places will be just a bit warmer than criteria to warrant Cold Weather Advisories given that we may have some wind that could keep temperatures from falling colder than they otherwise could. If winds end up being less, temperatures could fall a bit lower than currently forecast, though we would have less of a wind chill to worry about. All-in-all, a cold Thursday morning is expected and it's possible that some of the usual cold spots may see some wind chills briefly reaching down to -25 to -30.

A west-northwest flow pattern is looking to stick around for the foreseeable future. Another clipper and cold front could arrive Thursday night and bring another round of light snow. There could be several more chances for that going into the weekend and early next week. Some more potent shortwaves may be possible next week, bringing more of the same but possibly with some slightly higher snow accumulations if the trend right now remains the same.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1130 AM CST Tue Dec 2 2025

Predominantly MVFR/IFR ceilings at this hour with some MVFR visibilities (that continue to improve towards VFR) with some light fog and snow flurries. There is a pocket of low-level clearing around BRD, where VFR conditions can be expected for several hours this afternoon. Then, a cold front with light snow is expected to pass through tonight. Expect some ceiling and visibility reductions to MVFR/IFR as the wave of snow passes through. Winds switch to northwesterly and will become blustery for Wednesday.

MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 134 PM CST Tue Dec 2 2025

Breezy southwest winds will continue this afternoon and evening ahead of a cold front. Gusts up to 25 kt are expected at times, and Small Craft Advisories are in effect. A very brief lull in winds is expected this evening before the cold front passes through, then winds are expected to increase in speed from the northwest. 25-30 kt gusts are expected Wednesday into Wednesday night. Additional Small Craft Advisories will be needed, but we will hold off on issuing those until after current ones expire. There does remain a rather small (~10% chance) for gales mainly in the outer Apostle Islands for a brief period Wednesday evening, but more likely winds will remain just below that criteria. Expect wave heights to increase up to around 7 ft around the outer Apostle Islands as well.

Winds will switch to southwesterly again on Thursday with wind gusts quickly increasing Thursday into Thursday night. Gales are more likely (~40-60% chance), and wave heights around 6-8 ft will be possible especially for parts of the North Shore. Wind speeds are expected to decrease on Friday.

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

DLH WATCHES/WARNINGS/ADVISORIES

MN...None. WI...None. MARINE...Small Craft Advisory until 10 PM CST this evening for LSZ121- 140>148. Small Craft Advisory until midnight CST tonight for LSZ150.