textproduct: Duluth

KEY MESSAGES

- Showers and storms continue this morning, though the threat for severe storms has passed.

- Mostly dry with seasonable temps for mid week into the weekend.

- Next chance for precipitation will be Thursday evening.

UPDATE

Issued at 1248 AM CDT Tue Aug 4 2026

Thunderstorms throughout the Northland have weakened and the chances for severe weather have dwindled as well. There are still a few strong storms in the Minnesota Arrowhead, but are expected to move northeast over Lake Superior into Canada and weaken throughout the early morning. Unfortunately, this will lead to the Twin Ports as well as northwest Wisconsin missing out on the wetting rain falling with the storms.

The next chance for light precipitation with showers and thunderstorms will be Thursday evening with a weaker shortwave, and better chances over the weekend. Otherwise, look for a more seasonal, drier week this week with some sunshine.

DISCUSSION

Issued at 315 PM CDT Mon Aug 3 2026

This Afternoon and Tonight:

The Northland is in a bit of a lull, storm wise, this afternoon. Widespread cloud cover has kept temperatures in the 70s over the Arrowhead while elsewhere, temps are in the low to mid 80s. A stalled front is sitting just to our west, with more widespread showers and a couple storms remaining back over the Red River Valley. Through the rest of the afternoon, south winds will continue to increase, bringing warm air and moisture northward. This morning's INL sounding showed a substantial inversion (and a cap around 800mb). If there are enough breaks in the clouds to build more instability, an area of 50-60kts of bulk shear is nosing into the Lake of the Woods and Kooch county. If a storm can develop this afternoon, it could be strong to severe. If it can become surface based, there is a non-zero chance of a tornado. But, forcing looks weak, as we wait for the next shortwave to kick the front eastward.

The main impact period will be this evening into early Tuesday morning, as a broken line of storms along an approaching cold front strengthens to our west and moves into northeast MN. The airmass ahead of the front will be characterized by 1000-1500 J/kg (MUCAPE), 40-60kt of bulk shear right along the front, and lapse rates of at least 7C/km. Storms could be strong to severe, with large hail and damaging winds possible. Cannot rule out a tornado within the broken line.

Storms will continue to move across the region through the overnight period with the severe risk fading in the early morning hours as instability and wind features weaken. Scattered showers could linger across portions of northwest WI and the tip of the Arrowhead through mid morning tomorrow.

Mid week:

Surface high pressure moves over the region for for mid week as the upper level pattern supports broad troughing across much of the northern CONUS. Drier air will likely keep conditions dry despite the troughing aloft. A stronger shortwave arrives this weekend, bringing better rain chances. Temperatures stay in the 70s through Wednesday, then slowly climb through the end of the work week.

AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 626 AM CDT Tue Aug 4 2026

Stratus has developed behind the rain across northeast Minnesota. Areas of fog are developing as well. HIB has the greatest chance of seeing more fog this morning before the sun evaporates it. Otherwise, VFR conditions today with west to northwest winds up to 15 kts expected. Diurnal cumulus clouds are also expected this afternoon with cases at around 5 kft.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 1248 AM CDT Tue Aug 4 2026

Stronger winds ahead and along the line of storms moving through northeast Minnesota will lead to conditions hazardous to small craft all along the nearshore waters of western Lake Superior. A Small Craft Advisory is in effect until this morning.

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

FIRE WEATHER

Issued at 1248 AM CDT Tue Aug 4 2026

A combination of lower temperatures and lower dewpoints will lead to similar minimum RHs as yesterday, which are not expected to reach below 40% for today. Winds will be out of the west to northwest generally at 15 mph or less, but some gusts could reach 20 mph this afternoon across the Borderlands and the Arrowhead. Wednesday and Thursday will be drier, with minimum RH values down in the lower 30s and wind gusts 15-20 mph. Those are two days we are keeping an eye on, but no fire weather conditions are currently expected.

See the Fire Weather Forecast product for a more thorough breakdown of fire weather conditions.

DLH WATCHES/WARNINGS/ADVISORIES

MN...None. WI...None. MARINE...Small Craft Advisory until 8 AM CDT this morning for LSZ121- 140>148-150.