textproduct: Duluth

KEY MESSAGES

- A warmup is expected today with high temps 10-15 degrees above normal.

- A little cooler Wednesday through Friday while still on the warm side of normal.

- Another warmup Saturday with highs 15-25 degrees above normal.

- Widespread rain chances return Sunday and persist through Tuesday.

DISCUSSION

Issued at 300 PM CDT Tue Oct 6 2026

TONIGHT THROUGH FRIDAY NIGHT:

The cold front will progress farther southeast across the area tonight. Winds will remain gusty into early evening and may be gusty all night as cold air advection develops. The wind will keep temperatures from falling too far. Lows tonight will be in the low to upper 40s.

A stronger surge of cold air advection arrives Wednesday along with a northwesterly low-level jet. Diurnal heating will support wind gusts of 25 to 35 mph. Scattered to isolated rain showers may develop during the afternoon in response to the heating beneath colder air aloft. The best chance of a few sprinkles, at least, is found over the Arrowhead and portions of northwest Wisconsin. Temperatures will be a little cooler than today, though still a few degrees above normal, with highs in the upper 50s to upper 60s. Winds will diminish slightly Wednesday night and may remain gusty as cold air advection persists.

Thursday will see temps another few degrees cooler than Wednesday with highs in the middle 50s to middle 60s. Northwest winds will not be as strong. Friday temperatures trend a few degrees warmer.

SATURDAY INTO NEXT WEEK:

Heading into the weekend the upper-level pattern is expected to transition from split flow with a quasi-zonal wind field over the northern Plains and Canadian Prairies to a southwesterly pattern with a ridge building over the eastern Great Lakes. Surface low pressure is expected to develop in the lee of the Canadian Rockies Friday as a longwave trough digs into the northern US Rockies.

Warm and moist air advection will develop over the Upper Midwest Saturday morning which will result in well above normal temperatures. Highs in the middle to upper 60s are expected over the eastern Arrowhead with low to middle 70s over north-central and portions of central Minnesota. The warmest temperatures will be in the I-35 corridor east into northwest Wisconsin where upper 70s and low 80s are forecast as of this afternoon. The strongest isentropic ascent will be north of the area over northwest Ontario and precipitation chances are low.

A cold front will move into the region Sunday. Ahead of the front PWATs will increase to 0.75-1.3 inches due to the persistent theta-e advection in the southwest flow aloft. Rain chances will increase for the second half of the weekend in response to the ascent provided by the cold front. The front is forecast to stall over the Upper Midwest keeping isentropic lift and rain chances in the picture Monday and Tuesday.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1251 PM CDT Tue Oct 6 2026

Gusty southwest and winds this afternoon will turn westerly and northwesterly this afternoon and evening as a cold front passes over the terminals. Winds may remain gusty overnight. If winds can become calm at HIB and BRD, a brief period of LIFR fog is possible. The drier air in the wake of the cold front and winds expected overnight put the potential of fog at about 10%. Gusty northwest winds are forecast Wednesday. There is a small risk of low-level wind shear during the morning as a northwesterly low- level jet passes over the terminals. The latest forecast has the core of the jet around 3-5kft AGL providing a vector difference between the surface and 2kft of only around 20-25 knots.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 156 PM CDT Tue Oct 6 2026

Small Craft Advisories remain in effect through late this afternoon from Grand Marais to Grand Portage and from Port Wing to Saxon Harbor for south to southwest winds of 10 to 20 knots with gusts up to 25 knots and waves 1 to 4 feet. Winds veer westerly tonight and ease to 5 to 10 knots. Gusty west to northwest winds of 15 to 20 knots with gusts to 25 to 30 knots will return Wednesday, and another round of Small Craft Advisories will likely be needed. Winds and waves subside Wednesday night into Thursday. Gusty winds and building waves return Saturday and persist through early next week.

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

FIRE WEATHER

Issued at 156 PM CDT Tue Oct 6 2026

Drier air moves into the region behind a cold front starting tonight. Wednesday will see afternoon RH values between 30 and 45 percent. Winds will be gusty from the west and northwest at 10 to 18 mph with gusts of 20 to 30 mph. Afternoon relative humidity values on Wednesday will drop into the 30 to 45 percent range, with portions of northwest Wisconsin potentially seeing RH values below 30 percent. Minimum RH values remain 30 to 50 percent Thursday and Friday with lighter winds. Rain chances return Sunday and persist into the work week.

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 4 PM CDT this afternoon for LSZ121- 140-146>148-150.