textproduct: Duluth

KEY MESSAGES

- Seasonable temperatures today and 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 with brief gusty winds and small hail.

- Minimal precipitation in the extended forecast.

DISCUSSION

Issued at 251 AM CDT Thu Jul 9 2026

A fairly unremarkable summer day is in store for today, as surface high pressure meanders across the region. We could see some patchy dense fog this morning, especially near Lake Superior, which should burn off with visibility improving through the morning. Afternoon highs in the 70s to low 80s with dewpoints in the upper 40s to mid 50s.

Friday, a cold front from a weak surface low to our north is expected to pass from northwest to southeast through the day. We could see some precipitation in north-central Minnesota as early as Friday morning with this disturbance, if overnight convection in the Dakotas can hold itself together. Otherwise, generally expected some widespread scattered rain showers and thunderstorms to develop through the day, peaking in coverage and intensity Friday afternoon and evening. Model guidance suggests a possible 1000-2000 J/kg of MUCAPE with 30-40kts of bulk shear. If storms are able to develop, there's a chance that some of them could be on the spunkier side for north-central and NE MN bringing brief gusty winds, a quick downpour, small hail, and frequent lightning. Anyone with outdoor plans should keep an eye to the sky Friday.

As that disturbance keeping trucking south and east, it may be able to spur a little showery activity through the day Saturday for the North Shore and NW WI, but chances are fairly low (15-25%) at this time.

Sunday and into next week, models are in very good agreement that a robust upper level high will move into the central CONUS which should drive the heat and humidity up across the Northland. Model guidance is suggesting widespread temperatures in the 80s with several days of widespread 90s possible Sunday and Monday. This could come along with dewpoints in the 60s to low 70s. Heat headlines may be needed. With this set-up, any precipitation chances would likely stem from ridge-running disturbances that can bend the flow a bit at the northern edge of the upper level high to push a disturbance through. Global model guidance suggests that the next best chance for that would be sometime early to mid next week, maybe in the Tuesday-Wednesday timeframe, but confidence, and PoPs, are low.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1221 PM CDT Thu Jul 9 2026

VFR conditions with light and variable winds expected through the TAF period. There are low chances of light fog early Friday morning, mainly at DLH and HYR. Confidence is too low to include at this time.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 251 AM CDT Thu Jul 9 2026

A light onshore lake breeze is expected today, with some afternoon gusts of 10-15 knots possible for the Twin Ports and Apostle Islands to Chequamegon Bay. While no headlines are expected, small craft users shouldn't be surprised to have a little northeast chop to work with (less than 1 foot) this afternoon, which should die down quickly into the evening. Widespread marine dense fog is expected this morning, but model guidance is in decent agreement that it should pull back away from the coasts into the open water during the day. It may return once again overnight into Friday morning. A mostly light northeast wind is expected across Western Lake Superior Friday, which will once again 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 251 AM CDT Thu Jul 9 2026

Light northerly winds expected today with no precipitation. Afternoon dewpoints have trended downwards with high temperatures in the low 80s, making for a dry day today. Afternoon RH of 25-40% is expected across the Northland, with some locally especially dry spots near the Canadian border dropping below 25%. Friday, southerly winds return with some gusts of 10-15mph 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 the Northland, most likely Friday afternoon and 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...None.