textproduct: Duluth

KEY MESSAGES

- A line of severe thunderstorms could affect areas from Leech Lake to the Brainerd Lakes and into inland northwest Wisconsin this evening. Damaging winds top 70 mph and hail up to two inches in diameter are the primary threats with a secondary tornado threat.

- Temperatures arounnd 80 F for inland areas Friday and areawide this weekend.

- Another round of scattered showers and thunderstorms, possibly severe, Sunday PM when heavy rainfall is possible. Widespread rainfall is forecast into Monday night ending Tuesday morning.

DISCUSSION

Issued at 158 PM CDT Thu Sep 3 2026

For the rest of the day and into tonight, our primary focus shifts to an advancing mass of strong to severe thunderstorms currently organizing in the Red River Valley. This complex has moved up in time for impacts to the Northland this evening compared to earlier forecasts and is now timed to enter our north-central Minnesota zones around 5 PM this evening. The storms will ride a sharp instability gradient, driving southeastward primarily south of the Iron Range. The main hazards with this line will be damaging wind gusts and large hail up to the size of ping-pong balls, with the potential for wind-driven hail. As the system tracks eastward, the severe threat is expected to drop off rapidly an hour or two after sunset as it approaches the western Iron Range and the Twin Ports region, with the highest damaging wind threat remaining further south along the Interstate 35 corridor. Expect this activity to clear the Minnesota/Wisconsin stateline late this evening into the early overnight hours.

In the wake of the evening convection, lingering low-level moisture and cooling temperatures could produce dense fog tonight. Of particular note is a bank of very low stratus over the North Shore terrain ridge, which could significantly reduce visibilities for the Friday morning commute. Conditions will gradually improve by late Friday morning as ceilings lift and skies slowly clear out into the midday hours. Along the shores of western Lake Superior, strong and persistent northeast winds will continue to generate dangerous rip currents, keeping swimming conditions hazardous. Another Beach Hazards Statement may again by needed for Friday after the current one today expires late this evening.

Heading into the weekend, temperatures will gradually warm back into the upper-70s to low-80s under the influence of transient upper-level ridging. The break in active weather will be relatively short- lived, however, as the next surge of instability builds into the region by Sunday. We will be monitoring the potential for strong thunderstorms Sunday afternoon through overnight. While severe weather is not currently forecast for Sunday late PM, the environment will be characterized by an incredibly moist airmass, raising concerns for heavy rainfall that then lasts in Monday.

This moist, unsettled pattern will linger into Labor Day. Areawide rainfall chances peak on Monday with a 60 to 80 percent probability of precipitation as a low-pressure system lifts from the northern U.S. Plains into southern Manitoba. The precipitation is forecast to slowly clear out of the Northland by Tuesday morning. Looking further ahead, as the precipitation departs and broad troughing re-establishes itself, temperatures are expected to slowly cool to near normal through the latter half of next week.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1240 PM CDT Thu Sep 3 2026

Gusty easterly winds to 25 knots occur near Lake Superior shorelines today, closer to 15 to 20 knots at other terminals. A line of strong to severe thunderstorms is forecast in the Northland from 22Z to 06Z and could bring very strong wind gusts in excess of 50 knots and large hail around the size of a ping pong ball. For up to a few hours even after the strong to severe storms move through, gusty winds trailing the line could keep westerly winds gusting to 30 knots through 06Z this evening. LIFR to IFR conditions are then forecast into late Friday morning with some terminals seeing dense fog potentially. Skies slowly lift towards the end of this TAF period.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 201 PM CDT Thu Sep 3 2026

Small Craft Advisories remain in effect for the nearshore waters of western Lake Superior as strong northeast winds of 15 to 20 knots with gusts up to 30 knots generate waves of 2 to 4 feet. A line of thunderstorms is expected to cross the waters this evening, bringing threats of gusty erratic winds, large hail and lightning. Elevated northeast winds and hazardous small craft conditions are expected to persist through Friday before gradually subsiding Friday night. The ongoing Small Craft Advisories along the South Shore covering today are likely going to be needed again Friday daytime as the northeast winds ramp up again.

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

FIRE WEATHER

Issued at 202 PM CDT Thu Sep 3 2026

Afternoon relative humidity values will remain above 50 percent through the weekend as a moist airmass settles over the region. Gusty easterly winds will persist through Friday, especially near Lake Superior, before diminishing slightly over the weekend. Severe thunderstorms are possible tonight for parts of north-central into eastern Minnesota, but much lesser chances north and east of the Iron Range. These thunderstorms could produce large hail and gusty, erratic wind gusts to 70 mph. The strongest wind threat decreases quickly over northwest Wisconsin districts, but the large hail threat persists into the early overnight hours. The next round of strong to potentially isolated severe thunderstorms would be Sunday PM with widespread wetting rainfall forecast Monday.

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

DLH WATCHES/WARNINGS/ADVISORIES

MN...Beach Hazards Statement until 10 PM CDT this evening for MNZ037. WI...Beach Hazards Statement until 10 PM CDT this evening for WIZ001. MARINE...Small Craft Advisory from 10 PM this evening to 1 AM CDT Saturday for LSZ140>143. Small Craft Advisory until 1 AM CDT Saturday for LSZ144-145. Small Craft Advisory until 10 PM CDT this evening for LSZ148- 150.