Duluth forecast discussion

Key Messages

winds gusting 25-40mph peaking by midday, then diminishing into the evening.

- Dry conditions expected this weekend, with possible near-critical fire weather concerns Saturday.

- A very chilly night and widespread freeze into Saturday morning, then a gradual warming trend into and through next week.

Update

Issued at 258 AM CDT Fri Oct 16 2026

Additional rain showers continue to make their way across the region this morning. The main synoptic system is pushing off to the east across the Great Lakes, with some lingering wrap around precipitation being the main driver for the rain we are still seeing. These showers should steadily move east and diminish through this morning, with a little lingering lake enhanced rain possible into the early afternoon along the South Shore.

Closely following the surface low moving east is a notable surface high pressure building over the Dakotas, making for a prominent pressure gradient between the two. This is leading to wind gusts of 20-40mph over western to central MN, which will push across the rest of the Northland through this morning. The zenith for peak gusts should be observed between now and noon, with weakening gusts through the afternoon and evening.

Saturday, that high pressure should bring in dry air, along with some gusty southwest winds. First, low dewpoints and clearing skis should allow temperatures to plummet overnight, leading to morning low temperatures in the 20s Saturday. Then, a combination of afternoon relative humidity dropping to near 30% and southwest wind gusts of 20-30mph could lead to some near-critical fire weather conditions. Recent model guidance has trended slightly more moist with relative humidity due to cooler afternoon high temperatures, but there is still a wide spread in that variable which could affect final RH values. With a sunny day expected that should increase mixing, we're still keeping an eye on Saturday for fire weather concerns.

Discussion

Issued at 1251 PM CDT Thu Oct 15 2026

This afternoon, rain showers will continue to spread across the Northland as a surface low cuts across Wisconsin into the Great Lakes. This main band of rain currently moving through far northeastern Minnesota and northwest Wisconsin will continue to move east throughout this evening and overnight, with the heaviest rainfall falling across northwest Wisconsin. Models are still having trouble with a cold bias overnight, so brought up minimum temperatures for tonight due to cloud cover, as done in previous forecasts.

Wrap around showers will develop and more off-and-on rain showers are expected across much of the area in the late night and early morning Friday. Lake enhanced/effect rain showers will continue through most of Friday morning across portions of the South Shore as cold air moves over the relatively warm waters of Lake Superior. A few snowflakes could mix in across far northern Minnesota during the overnight hours, but no accumulations and no impacts are expected. Strong north winds will surge behind the departing boundary, gusting between 25 and 35 mph inland and up to 45 mph near Lake Superior, before conditions subside and skies clear late Friday afternoon.

High pressure will build across the Upper Midwest Friday night into Saturday, bringing a return of sunny skies and dry air. RHs increased significantly Saturday with the initial population of forecast data, so decreased them again to better account for dry air aloft that will likely mix down to the surface that day. No fire headlines are anticipated at this time, but fire weather conditions will still be near critical with the combined lower RH of 25 to 30 percent and gusty southwest winds of 20-30 mph expected that day. Under this system, temperatures will increase back toward sixty degrees through the weekend into next week.

On Sunday, an upper-level shortwave will pass north of the international border, dragging a mostly dry cold front through our region with only scattered passing clouds. Winds will follow as this system passes with gusts 20-30 mph in northwest Wisconsin. RH values between 30 and 40% will lead to elevated fire weather conditions with higher winds, but not anticipating any fire headlines needed. Behind this boundary, upper-level ridging will become the dominant pattern driver across the Great Lakes. This synoptic regime will maintain dry, mostly clear, and unseasonably mild weather across our area through Monday, with afternoon temperatures warming well into the sixties.

Dry and quiet weather will persist into Tuesday as the upper ridge remains centered over the region, keeping temperatures mild. By Wednesday, a weak passing upper disturbance will bring an increase in cloud cover along with a slight chance of afternoon rain showers. However, any precipitation will be light and widely scattered, with dry conditions still favored overall at this point.

Aviation /06Z Tafs Through 06Z Saturday/

Issued at 1244 AM CDT Fri Oct 16 2026

MVFR to IFR ceilings continue early this morning at all terminals with areas of rain showers. Those low ceilings and rain showers should slowly make their way out of the area through mid morning, with conditions returning to VFR for all terminals by midday. Gusty north winds will move into the region from west to east, with gusts of 25-30 knots possible, peaking between 12-18Z this morning, and then steadily diminishing through the afternoon and evening. Expect fairly calm conditions and clear skies overnight into Saturday morning.

Marine /For Nearshore Waters Of Western Lake Superior/

Issued at 258 AM CDT Fri Oct 16 2026

A very strong period of north winds will affect Western Lake Superior this morning, with gales expected through midday. Winds should diminish through the afternoon, but a Small Craft Advisory will likely be needed until early this evening. Winds turn to become southwesterly through the weekend, with some strong gusts possible, especially in the afternoon and along the South Shore. Max gusts could approach gale-force Saturday afternoon and evening, but its still a little uncertain at this time. Wind gusts over 30knots are likely (70% chance), but getting all the way to 34knots is less certain, especially for the North Shore and into the open waters. Small Craft Advisories are likely, and a Gale Warning is possible.

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

Fire Weather

Issued at 258 AM CDT Fri Oct 16 2026

Very strong northwest winds are expected this morning, peaking in the late morning to around noon, and then slowly weakening through the afternoon and evening. This will accompany diminishing rain showers, which should be largely out of the region by mid morning. As drier air moves in behind these showers, afternoon relative humidity should drop to around 40-50%. Saturday will be a day to watch for fire weather concerns, though recent model guidance has backed off on the very dry air we were expecting. Minimum afternoon relative humidity could still drop to 30-40% along with southwest winds gusting 20-30 mph. Gusty southwest winds continue into Sunday, with afternoon minimum relative humidity recovering slightly, expected to be in the 35-45% range.

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

Dlh Watches/Warnings/Advisories

MN...None. WI...None. MARINE...Gale Warning until 1 PM CDT this afternoon for LSZ121-140>148- 150.

UPDATE...Levens DISCUSSION...KML AVIATION...Levens MARINE...Levens FIRE WEATHER...Levens