textproduct: Duluth

KEY MESSAGES

- Pockets of half-mile visibility this morning from widespread fog that clears early to mid morning today.

- Multiple night with frost and freeze potential return Thursday night and through early next week.

- Next chance for light rain showers is Saturday.

DISCUSSION

Issued at 203 AM CDT Wed Sep 30 2026

Early this morning, the stationary front that brought widespread light rainfall yesterday has finally started to push eastward and resulted in all rainfall now well southeast of the Northland. Satellite imagery shows slowly expanding very low-based stratus sky cover that will linger in these overnight hours, creating pockets of half-mile visibility in fog through the morning commute hours. Dense fog is not currently forecasted in most areas, but we will monitor observation trends for any potential headline needs towards the dawn hours. This stratus will slowly clear late this morning into mid-day today. Once the sun breaks out, expect dry weather today under seasonably very warm temperatures. Highs will reach the 70s across the Northland, with pockets approaching 80 degrees for northwest Wisconsin.

A stout dry cold frontal passage is on track for late tonight into early Thursday morning. This front creates a wind shift to the northwest and ushers in a notably cooler air mass for Thursday. High temperatures will drop 10 to 15 degrees Thursday compared to today, but it will actually feel fairly normal for very early October. Along with the cooler air, expect breezy northwest winds Thursday gusting 20 to 30 mph mainly in far northern Minnesota, more likely only up to 20 mph along and south of US Hwy 2 in the rest of the region.

The winds will relax as high pressure settles in, setting the stage for a chilly end to the work week. There is a fairly widespread frost likelihood Thursday night into Friday morning, and headlines are expected to be needed in time. Pockets of freezing temperatures are anticipated mainly for the Minnesota Borderlands to the Iron Range and inland northwest Wisconsin. Dry weather continues through Friday night as the region remains under the influence of the surface high pressure system.

An incoming shortwave trough will move first into north-central Minnesota Saturday morning, then spread across northeast Minnesota to northwest Wisconsin by Saturday afternoon and evening. Precipitation types remain as all rainfall and brings up to a quarter inch of new rain.

Beyond the rainfall Saturday, the other main concern will be a frost potential that lasts each night this weekend. However, the threat becomes more widespread again with even better chances of sub-freezing temperatures for Sunday night into Monday morning. A return to warm air advection sets up Monday, allowing temperatures to warm again by Tuesday, and especially by mid-next week when highs climb back to well-above normal.

AVIATION /06Z TAFS THROUGH 06Z THURSDAY/

Issued at 1229 AM CDT Wed Sep 30 2026

IFR to LIFR ceilings continue throughout the night. Patchy fog is leading to visibilities rising and lowering, which is expected to continue throughout the night as well. INL may see some clearing skies before sunrise if the stratus gets advected east, though that is looking unlikely at this time. Fog and stratus is expected to slowly rise throughout the morning and should all be VFR by the afternoon.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 205 AM CDT Wed Sep 30 2026

Southwest winds of 10 to 15 knots today, with occasional gusts approaching 20 knots offshore of Grand Portage. Pockets of fog are expected through sunrise before clearing this morning. A stout cold front will drop across the lake late tonight, abruptly shifting winds to the west and northwest. These northwest winds will strengthen for Thursday, with gusts of 20 likely and potentially around 25 knots. Small Craft Advisories may be needed Thursday.

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

FIRE WEATHER

Issued at 207 AM CDT Wed Sep 30 2026

Following recent rainfall, drier air moves into the region today and persists through the end of the week. Afternoon relative humidity values are forecast to fall into the 30 to 45 percent range on Thursday and Friday. A dry cold front passage late tonight will lead to gusty northwest winds of 20 to 25 mph for Thursday. Moisture improves slightly on Saturday as a weak disturbance brings scattered light rain showers...although a wetting rainfall is not expected for most districts. Cool and dry conditions occur Sunday.

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.