textproduct: Duluth

KEY MESSAGES

- The next chance for showers and storms will be late Monday night through Tuesday.

- Severe storms are possible, particularly Tuesday afternoon and evening with the passage of a cold front.

- Seasonal, dry conditions return for the later part of next week.

DISCUSSION

Issued at 140 AM CDT Sun Aug 23 2026

Surface high pressure settling into the area this morning has made good radiational cooling conditions across the Northland. Fog has already developed in a few of our more fog prone locations this morning, and we are likely to see additional development through early Sunday morning. Any morning fog will quickly burn off after sunrise on Sunday, giving way to a very pleasant and quiet late August day. The high pressure will providing mostly sunny skies and light northwest winds. Minimum relative humidity values will dip into the 30 to 40 percent range during the afternoon hours. Tonight will feature another round of mostly clear skies and chilly overnight low temperatures in the forties with a few locations possibly dipping into the upper 30s.

Late Sunday night into Monday daytime, we will have a leading wave of elevated warm air advection and a warm front pass west to east across the area. Some models are producing showers and storms with it, but the low level dry air appears to be too stout to allow any precipitation to reach the ground. Also, most models are completely dry for us on Monday, and have decided to leave the forecast dry for now. I do expect an increase in cloud cover and perhaps some elevated radar echoes, but that dry air is likely to keep the low levels dry.

Precipitation chances increase as the main upper level shortwave moves across the area late Monday night through Wednesday. Monday night into early Tuesday we have some elevated instability, so we will likely have some rumbles of thunder overnight, but am not concerned for severe storms. We do have an area of Marginal severe risk just to our west from SPC, but suspect this may shift farther west based on the latest models. If we get any strong storms, they would be towards Tuesday morning. Tuesday will be warm and more humid, with some surface based instability developing during the afternoon and evening hours. Then, just as the upper level shortwave moves across the area and deep layer shear parameters increase, I expect another wave of showers and thunderstorms to move through the area, which will have the potential for strong to severe storms. While things look interesting now, we will have to monitor for timing or other changes that may change this. Showers and non-severe storms will redevelop across the area on Wednesday in the cyclonic flow behind the upper level shortwave. Wednesday and Thursday will be cooler again. The cyclonic flow may help to generate isolated showers again on Thursday, though the incoming dry air may quash them. We currently have a dry forecast, but if we have a bit more moisture, that may change.

High pressure and northwest flow aloft return for the latter portions of the work week, bringing a return to dry conditions across the Northland for Thursday into Friday. Precipitation chances remain below fifteen percent through the end of the period.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 629 AM CDT Sun Aug 23 2026

Some patchy MVFR to LIFR fog and dense fog early this morning, with with BRD and HIB seeing the worst conditions in fog. The fog is expected to burn off shortly after sunrise this morning in the 12-14Z timeframe. VFR conditions under mostly sunny skies develop today along with light winds under high pressure. There is some signal for patchy fog/dense fog development again tonight, with the best probabilities at HIB and HYR, though most terminals may see at least some fog.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 140 AM CDT Sun Aug 23 2026

Northwest winds gusting up to twenty knots will ease overnight into Sunday morning over the nearshore waters of western Lake Superior, with waves subsiding to one to two feet. Winds to become light and variable during the day on Sunday as high pressure settles over the area. The nearly calm winds linger overnight before gradually turning southeast on Monday, but generally remaining under 10 knots through the day. Waves to generally be 1 foot or less Sunday night and Monday.

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

FIRE WEATHER

Issued at 140 AM CDT Sun Aug 23 2026

Winds will be significantly weaker today than yesterday as a ridge of high pressure builds into the area. For most areas, even wind gusts will be less than 10 mph. Minimum relative humidity will drop a bit lower to 30 to 40 percent. A few places could dip below 30 percent. Relative humidity remains low for northwest Wisconsin on Monday, but northern Minnesota RH values will increase to over 35 percent. Winds will become southerly and may gust around 10 mph during the afternoon. Shower and thunderstorm chances increase for Monday night through Wednesday, with RH values remaining above 40 percent both days. Precipitation chances are highest along and north of the Iron Range, but most areas have at least a 40 percent chance of measurable rainfall.

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.