textproduct: Duluth

KEY MESSAGES

- Overnight and early morning showers and thunderstorms to move east of the CWA by late morning.

- Near-normal temperatures for August are expected through this week.

- There are chances for rain showers and non-severe thunderstorms about every other day.

UPDATE

Issued at 233 AM CDT Sun Aug 9 2026

An area of showers and a few non-severe thunderstorms will move across the region early this morning, driven by a weak upper level disturbance. The highest rainfall amounts will be found across the Iron Range and Arrowhead, where localized totals between a quarter and half an inch are possible before rain shifts eastward across Lake Superior and parts of northwest Wisconsin. Skies will clear from west to east by afternoon, yielding a mostly sunny and pleasant afternoon.

Generally quiet conditions and clear skies will prevail tonight as weak high pressure settles over the Upper Midwest. Light winds and radiational cooling will promote patchy fog development during the late overnight and early morning hours, particularly across parts of northwest Wisconsin. Any fog will clear quickly after sunrise Monday, leading to a mostly sunny day.

A series of weak atmospheric disturbances riding along a stalled front to the south will reintroduce periodic rain chances starting Monday afternoon and night and continuing through Wednesday. This pattern will help create a 10 to 30 percent chance of scattered showers and non-thunderstorms every day or two. The severe weather threat will stay focused well to our south across southern Minnesota and southern Wisconsin. This will also keep temperatures near to just below normal through this week.

DISCUSSION

Issued at 1200 PM CDT Sat Aug 8 2026

Increasing cumulus clouds and a slight haze high in the sky will be the main weather story for this afternoon and evening as wildfire smoke drifts overhead. Despite the haze, it will be a very pleasant and comfortable day across the Northland. Afternoon highs will reach the middle 70s to the lower 80s, and with humidity remaining relatively low.

The International Border will likely see some high-based showers passing through that area of far northern MN this afternoon to early evening, but very dry low-levels limits much of any precip from reaching the ground and to virga. The forecast grids for that area this afternoon remain without any weather mentions for this case.

A weak shortwave rotating through a deeper vertically stacked Hudson Bay Low pressure skirts through southeast Manitoba and northwest Ontario tonight. This will bring a band of high-based rain showers into northeast Minnesota late this evening, through the overnight and into early Sunday morning. If you live along and north of the Iron Range into the Arrowhead, you could see the highest rainfall totals, localized up to half an inch. Late tonight into Sunday morning, mid-level instability builds into central MN and northwest Wisconsin on the nose of an incoming low-level jet. This setup may (20-30% chance) help trigger a few non-severe isolated thunderstorms across east-central MN and northwest Wisconsin through Sunday morning. This will also be a short period of increased dewpoints early Sunday that keeps a wetting rainfall around a quarter-inch of localized rainfall possible for northwest Wisconsin. Severe weather is not expected tonight into Sunday morning.

Looking ahead to next week, the Northland will remain on the cooler side of a stalled weather front located to our south. This setup will keep our temperatures near to slightly below normal going into the early part of mid-August. The weather pattern will also keep with the pattern of a weak system passing through the Upper Midwest and helping create a 10 to 30 percent chance of scattered showers and thunderstorms every day or two. The severe weather threat though is expected to stay focused well to our south across southern Minnesota and southern Wisconsin.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 620 AM CDT Sun Aug 9 2026

An area of showers and isolated thunderstorms moving east- southeast across northeast MN this morning. For now, it appears these will stay away from any of the terminals. Outside these, VFR conditions to prevail. Surface winds remain light and variable, generally under 10 knots. After these showers move east, conditions to remain VFR today and this evening. After 05z tonight, fog should develop at some of the terminals, and have included MVFR/IFR visibilities for KDLH, KHIB and KHYR. Have left out of KINL and KBRD for now, but it may need to be added.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 233 AM CDT Sun Aug 9 2026

Winds across western Lake Superior will remain light today and tonight around 5 to 10 knots with waves of 1 foot or less. Southwest winds increase slightly on Monday with late morning and afternoon gusts up to 15 knots, mainly along the North Shore. Scattered showers and isolated thunderstorms early this morning may bring occasional lightning. Shower and thunderstorm chances return Tuesday night into Wednesday.

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

FIRE WEATHER

Issued at 233 AM CDT Sun Aug 9 2026

Showers and a few thunderstorms moving across the area early this morning have brought scattered rainfall amounts between 0.1 to 0.5 inches, mainly along and north of the Iron Range. Once these showers move east of the area, winds will become northwest around 5 mph, with RH values dropping to between 40 and 50 percent this afternoon. Northwest Wisconsin will be slower to clear, and RH values will remain higher there. Clear skies, light winds and lingering low level moisture will make patchy fog likely. Monday conditions will be slightly drier with RH values dropping to between 35 and 45 percent, with northwest winds around 5 to 10 mph. Periodic non-severe thunderstorm chances return every 36 to 48 hours through midweek.

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.