textproduct: Duluth

KEY MESSAGES

- Seasonable temperatures continue Friday before a notable warm up through the weekend with increasing humidity. Potentially dangerous heat and humidity is possible Sunday, Monday, and into early next week.

- Scattered rain showers and thunderstorms are possible Friday. An isolated thunderstorm Friday afternoon and evening could be strong to severe with brief gusty winds and large hail. A strong storm or two is also possible Saturday afternoon, mainly across northwest Wisconsin.

- Minimal precipitation in the extended forecast, with low rain chances limited to mid to late next week.

DISCUSSION

Issued at 1252 PM CDT Thu Jul 9 2026

Higher pressure sits over the region today with light and variable winds. Temperatures are close to seasonable, with mostly sunny skies. Although, seeing the afternoon cu develop just inland along the lake breeze. Would not rule out a brief shower this afternoon along those breezes. Any activity diminishes this evening. Cannot rule out fog again overnight, as marine fog expands inland, mainly along the South Shore.

There is a weak cool front back to our west, associated with an upper level disturbance, that will push slowly eastward tonight and Friday morning. There is a low chance decaying showers or storms will push into the Northland late tonight, but the airmass will be less supportive of storms by that time, with little to no CAPE and lower lapse rates. Tomorrow, the front will arrive and provide a focus for shower and storm development, with 1000-2000 J/kg of MUCAPE and around 20kts of bulk shear during the afternoon. Lapse rates are not great tomorrow with increasing mid level heights as an upper ridge approaches. Coverage might not great, but if a storm can get going and sustain itself, large hail will be possible. There is a Marginal risk (1 out of 5) across the Brainerd Lakes region, mainly for large hail.

Another weak disturbance arrives Saturday, and could interact with what will likely be a weak frontal boundary sitting across the area. With plenty of instability around with increasing temps and moisture, cannot rule out a few showers or storms, mainly across northwest WI during the afternoon.

A strong upper ridge builds across much of the CONUS for early next week, bringing the heat with it. Temperatures will be close to record values Sunday through Tuesday, and 10+ degrees above normal for mid July. Moisture will also hang around, with dewpoints in the 60s to lower 70s. Will likely need heat headlines with this combination of temperatures in the 90s and increased moisture for Sunday through Tuesday. Little to no rain is expected under the ridge. The ridge will start to pull back to the west mid week, and could see weak disturbances drop down into the Northland providing low rain chances.

AVIATION /06Z TAFS THROUGH 06Z SATURDAY/

Issued at 1234 AM CDT Fri Jul 10 2026

Mostly VFR conditions are expected through this morning. Some patchy dense fog could affect DLH and HYR through sunrise. Areas of showers and thunderstorms are possible through the day, most likely in the afternoon and evening. However confidence is fairly low for now, so have gone with mostly VCSH groups during the most likely time range. Confidence is slightly higher for BRD, so have added an actual SHRA group there in the afternoon. Most precipitation activity should come to an end through the evening. Expect fairly light southerly winds through the TAF period outside of any thunderstorms that can develop.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 1252 PM CDT Thu Jul 9 2026

Winds are generally light and variable this afternoon, but would not rule out a wind gust to 10kts at the head of lake where winds are more persistently out of the northeast. Any stronger winds will diminish this evening. Marine dense fog from this morning has pulled back from the coasts into the open water. While guidance is overzealous with keeping it closer to the coast through this afternoon, the setup does support the fog returning overnight, particularly to the Outer Apostles and the South Shore.

A mostly light northeast wind is expected across Western Lake Superior Friday, which will lead to some less-than-one-foot chop in the afternoon, but nothing hazardous. Some rain showers and thunderstorms may be able to develop Friday afternoon and evening, moving from northwest to southeast across the lake. An isolated thunderstorm or two could become strong with brief gusty winds, a quick downpour, small hail, and frequent lightning. Very isolated shower and thunderstorm development is possible again Saturday, but less likely than Friday.

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

FIRE WEATHER

Issued at 1252 PM CDT Thu Jul 9 2026

Winds are generally light and variable today, with no precipitation expected. With temperatures warming into the low to mid 80s, expect afternoon RH values to drop into the 25-40% range, with some locally especially dry spots near the Canadian border dropping below 25%. Friday, southerly winds return with some gusts of 12-18mph possible in the afternoon. This should bring with it some improved humidity (afternoon RH 35-50%) and a 20-40% chance for some scattered showers and thunderstorms across north central Minnesota during the afternoon with low chances shifting eastward to the Arrowhead in the early evening. Any accumulations would be fairly light, a couple hundredths to a couple tenths. Temperatures warm through the weekend, but dewpoints in the 60s remain, so afternoon RH should fairly consistently drop into the 35-45% range, with the chance for some particularly dry spots to reach 30%. Some breezier southwest winds are possible Sunday for north-central Minnesota.

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

DLH WATCHES/WARNINGS/ADVISORIES

MN...None. WI...None. MARINE...Dense Fog Advisory until 10 AM CDT this morning for LSZ121- 140>148-150.