textproduct: Duluth

KEY MESSAGES

- A wintry mix, including freezing rain, is expected tonight into Tuesday morning with a light glaze up to locally 0.10 inches of ice for northeastern Minnesota and the South Shore. 1 to locally 3 inches of snow are possible in the Borderlands.

- Thunderstorms are possible in northwest Wisconsin this evening and early Tuesday morning.

- There is a 20% chance for snow squalls late Tuesday afternoon into early evening for areas along and north of the Iron Range.

- A couple Colorado Lows are poised to bring two rounds of snowfall and possibly some wintry mix to the area; one round on Wednesday night through Thursday and another round Friday night through Saturday. The second Colorado low has the potential to bring significant snowfall to the Northland.

DISCUSSION

Issued at 228 AM CDT Mon Mar 30 2026

Today - This Evening:

Largely zonal flow aloft today and this evening as surface low pressure tracks primarily to our south. Some moisture today could produce some light snow showers (20-40% chances) in far northern MN/near the International border this morning and afternoon, though some dry air in the lower portions of the atmosphere may prevent this snow from reaching the ground. Portions of NW WI will be closest to a surface warm/stationary front today into this evening, with most of the Northland remaining on the cold side of this boundary. Add in easterly flow off of Lake Superior, and we will see quite the temperature gradient across the area. High temperatures are forecast to be in the 50s in the Brainerd Lakes, 50s to low 60s in inland NW WI, and 40s for much of the remainder of the Northland aside from upper 30s in the vicinity of Lake Superior. There is a small chance for a couple thunderstorms this evening in inland NW WI atop a low-level inversion, but severe weather is not expected due to limited instability and a tall, skinny instability profile with MUCAPE values around 600 J/kg or less.

Tonight - Tuesday:

The aforementioned low-level inversion will also play a factor in aiding in a messy wintry mix potential tonight into Tuesday morning as a low pressure system slides through southern MN/south-central WI. Forecast atmospheric temperature profiles show a range from light rain in far southern portions of the Northland to a wintry mix of light rain, freezing rain, light snow, and even some brief sleet potential in the South Shore, Brainerd Lakes, Twin Ports, and much of northeast Minnesota. Ice accumulations have stayed pretty consistent, generally as a light glaze to a few hundredths for most of the area, with pockets up to around 0.10 inches in north-central Minnesota. Colder atmospheric temperature profiles towards the International Border favor accumulating snow as the primary precipitation type there, generally ranging from 1 to locally 3 inches.

As this system departs on Tuesday, expect some isolated to scattered wrap-around light snow showers Tuesday afternoon into early evening, primarily along and north of the Iron Range. Given steep low-level lapse rates and breezy northwest winds, there is a low (20% chance) that a few snow squalls could develop from these snow showers, though confidence is low at the moment.

Wednesday:

Brief high pressure moves through the region on Wednesday, bringing a drier Wednesday with high temperatures in the 30s to low 40s, coldest near Lake Superior due to breezy easterly winds. This quiet period will be short as an amplified pattern sets up for late this week into this weekend.

Active Wintry Pattern Late This Week - Weekend:

Two prominent Colorado lows are poised to take aim at the Great Lakes region, one on Wednesday night into Thursday and a second one on Friday night through Saturday. Both systems will have access to plenty of moisture from the Gulf and modified moisture from the Pacific.

Latest Euro and GFS global ensemble low tracks have trended north over the past 12-18 hours regarding the Wednesday night into Thursday Colorado low, with most tracks now progged to go through south-central Wisconsin into northern Lake Michigan. This would place portions of the Northland in the precipitation shield on the northwest side of the low pressure system. While most of the Northland would be poised to see snow with this system, slight wobbles in the forecast track of the low could introduce some mixed precipitation potential in NW WI depending on how atmospheric temperature profiles pan out. There is a 20-60% for snow accumulations of 3"+ and ice accumulations of at least a trace with this system, with the best potential for ice accumulations in NW WI.

Naturally, the Friday night into Saturday system has more spread in ensemble low tracks at this range, varying from the lower peninsula of Michigan to western Lake Superior. It'll be another situation where low track/timing will dictate the temperatures at the surface and temperature profiles aloft as the heaviest precipitation moves through. Right now precipitation looks to be mostly snow, but can't rule out a wintry mix for portions of the area again. This system appears to be a bit more wound up/vertically stacked with a closed low aloft relative to the late Wednesday-Thursday low. As a result, it may have a more prominent dry slot and TROWAL regions in the southwestern and northwestern portions of the surface low pressure, respectively. Depending on where these features set up relative to the Northland will dictate whether or not we see significant snowfall potential with this system as snowfall probabilities in the ensembles continue to trend upwards.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 544 AM CDT Mon Mar 30 2026

Largely VFR conditions prevail until this evening. Light snow showers on radar in northwest Minnesota have been occasionally reaching the ground with VFR conditions. These will be possible mainly at INL this morning into mid afternoon, and could briefly produce MVFR conditions at times. Expect MVFR ceilings to arrive at most terminals later this evening and tonight ahead of an approaching low pressure system, nearing IFR ceilings by the end of the 12Z TAF period. Mixed wintry precipitation chances return to northeast Minnesota and northwest Wisconsin tonight into Tuesday morning, with the best potential at INL and HIB late tonight. PROB30s elsewhere where potential is less certain that the atmosphere will saturate completely to produce snow/rain/freezing rain by 12Z Tuesday. Can't rule out some IFR visibilities with the wintry mix very late in the 12Z TAF period. Locations near and southwest of Lake Superior will see the strongest east to northeast winds today at 20 to around 25 kt, especially DLH.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 228 AM CDT Mon Mar 30 2026

A tightening pressure gradient ahead of an approaching low pressure system will cause northeast winds to increase rapidly today into Tuesday. Expect wind gusts of 20 to 30 knots and wave heights building to 4 to 8 feet for much of western Lake Superior, with a Small Craft Advisory in effect. Gale potential at the head of the Lake is less than 20%. Winds will shift to the northwest by late Tuesday as the low pressure system departs with winds dropping off to 20 kt or less.

Another period of strong winds and higher waves arrive with a Colorado low pressure system Wednesday evening into early Friday and again with another low pressure system late Friday into this weekend. There is a good (50-70%) probability of widespread gale-force winds and a low (20%) probability for storm-force wind gusts Thursday and Thursday night.

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 from 1 PM this afternoon to 11 PM CDT Tuesday for LSZ140>148-150.