textproduct: Duluth

KEY MESSAGES

- Dense fog on Lake Superior and nearby land along the North Shore through early this morning. Visibility down to one- quarter of a mile is expected on land and below 1 mile on Lake Superior.

- Additional, non-severe showers and storms on Thursday and again on Friday with cooling temperatures into this weekend and early next week.

- Thunderstorm potential returns mid to late next week with a very slight warming trend.

UPDATE

Issued at 640 AM CDT Thu Jun 11 2026

The Dense Fog Advisory in southern Cook County was cancelled. There is still some patchy dense fog near the immediate Lake Superior shoreline from Grand Marais to Grand Portage, but cameras and observations in those areas are showing visibility improvement.

DISCUSSION

Issued at 217 AM CDT Thu Jun 11 2026

Early this morning, cameras, satellite, and surface observations show dense fog in southern Cook County as fog streams in off of Lake Superior. Because of this, a Dense Fog Advisory was issued through shortly after sunrise this morning. A cold front sweeping across the Arrowhead will bring a less humid airmass in behind it, which should help to sweep away the fog in the daylight hours today.

Today:

For today, low pressure sliding northeast through Iowa into central Wisconsin will bring a return of rain showers, first in the Brainerd Lakes to NW WI, and then into the Arrowhead in the afternoon. As the system departs this evening into tonight, precipitation will end from west to east this evening into early tonight. Some weak instability will be present, which could produce a few embedded, non-severe storms this afternoon into early evening. Total additional rainfall in the Northland should range from around one tenth of an inch or less along and north of a Brainerd to McGregor to Silver Bay Line, with amounts increasing gradually to around 0.25-0.4" into NW WI. High temperatures will be more mild today in the 70s (slightly cooler immediately near Lake Superior), alongside much more comfortable dewpoints and breezy southwest winds.

Friday:

Cyclonic flow aloft sets up for a breezy Friday as a low pressure system stalls out over the far NE Manitoba/NW Ontario border and brings a secondary cold front through the area. There isn't a large of moisture associated with this system (fairly average PWATs around 0.6-1", highest in our south) and temperatures will be mild in the upper 60s north to mid/upper 70s south across the area. Expect some scattered light shower activity mainly along and north of the Iron Range Friday morning and afternoon in the cyclonic flow regime. Steep low-level lapse rates would also allow for a few hundred J/kg of MLCAPE to develop Friday afternoon into early evening from the Brainerd Lakes east into early NW WI that could produce a few widely scattered thunderstorms. While this activity is not expected to be severe, 40-50 kt of 0-6km bulk shear and mid-level lapse rates around 6-6.5 C/km combined with the limited instability and steep low-level lapse rates could produce small hail and locally gusty winds to 40 mph with any thunderstorms.

This Weekend - Early Next Week:

Cyclonic flow aloft persists into this weekend and early next week, leading to a pattern of near to slightly below normal temperatures, with highs largely in the mid 60s to mid 70s and lows in the 40s to around 50F from Saturday through Tuesday. This cyclonic flow will have occasional shortwave energy moving through it, so this period will not be completely dry with most days having daily 10-30% chances for rain showers and perhaps a few general thunderstorms, with best coverage and potential in the afternoons through early evenings. Saturday and Sunday will have the least potential for rainfall. Also look for breezy daytime winds most days.

Mid - Late Next Week:

Several global ensemble members depict an Alberta Clipper-like system moving through the Upper Midwest sometime in the next Wednesday/Thursday timeframe. Depending on timing and how this system tracks, it would bring slightly higher chances (30-40%) for scattered showers and thunderstorms. Still a bit too early to pinpoint any severe weather potential with it. Immediately ahead of this system could also see slightly warmer temperatures in the upper 60s to upper 70s, warmest inland from Lake Superior.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 640 AM CDT Thu Jun 11 2026

Some patchy fog still around HYR for the next hour or so, but visibilities will quickly be improving. Expect largely VFR conditions for northeast Minnesota and northwest Wisconsin until showers push back into much of the region from the south starting at HYR and BRD mid to late this morning and then spreading northeast. Precipitation then ends from west to east this evening into very early tonight. Still can't rule out a 20 percent chance for a few storms with the showers, but potential remains too low regarding impacts to terminals or their vicinities to include in the TAFs with this update. VFR to periodic MVFR visibilities accompany the showers, with MVFR ceilings also forecast to push into HYR this afternoon and evening and potentially INL later tonight.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 640 AM CDT Thu Jun 11 2026

The Marine Dense Fog Advisory was extended through 10 AM CDT for Grand Marais to Grand Portage. Satellite and cameras still show some fog up that way that should recede in the next 1-3 hours.

Southwest winds persist throughout today and tonight, generally at 15-20 kt, but occasional gusts up to 25 kt can't be ruled out at times in the Outer Apostles and portions of the North Shore, particularly this afternoon and tonight. Hazardous conditions for small craft may be possible, but confidence remains too low for a Small Craft Advisory. Additional scattered rain showers are possible today.

Friday will also see southwest winds, but on the stronger side at 22-28 kt, which will also lead to building wave heights of 3-5 ft for the Outer Apostle Islands and Grand Marias to Grand Portage. Small Craft Advisories will likely be needed for much of our western Lake Superior nearshore waters. Breezy west to northwest winds of 15-25 kt are also in store for this weekend, so additional hazardous conditions for small craft could occur.

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

FIRE WEATHER

Issued at 217 AM CDT Thu Jun 11 2026

A low pressure system passing to our south will bring scattered to widespread showers and a few embedded, non-severe storms for much of the Northland with much less coverage in north-central Minnesota. Additional rainfall amounts range from around 0.1" or less along and north of a Brainerd to McGregor to Silver Bay line and gradually increasing amounts to 0.25-0.4" in northwest Wisconsin. Given drier low-levels of the atmosphere, min RH drops to 30-45% in northeast Minnesota and will be lowest in the Iron Range and Arrowhead. Other areas remain above 45%. Winds will also be breezy out of the southwest today at 15-25 mph, strongest along and north of the Iron Range.

Additional isolated to scattered rain showers and perhaps a few non- severe storms are forecast for Friday, though many areas will likely remain dry. Friday will be another breezy day with westerly wind gusts of 20 to 30 mph and min RH of 35-45%.

This weekend will be primarily dry and cooler, with daytime isolated showers/storm chances at around 10-20%. Breezy west- northwest to northwest winds are also in store along with min RHs of 30-45% on Saturday and 25-40% on Sunday, being driest in the I-35 corridor to northwest Wisconsin Pine Barrens.

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

DLH WATCHES/WARNINGS/ADVISORIES

MN...None. WI...None. MARINE...Dense Fog Advisory until 10 AM CDT this morning for LSZ140.