textproduct: Duluth

KEY MESSAGES

- Drier with seasonable temperatures today, then gradually warming up again and becoming hot this weekend. Heat Advisories may be needed for portions of the Northland Saturday through Monday.

- Breezy winds, fairly low relative humidity, and hot conditions could lead to elevated fire weather conditions for portions of the area on Friday into this weekend.

- A few areas of storms possible for the end of the work week into the weekend. Some strong to severe thunderstorms are possible at times, including late Friday afternoon into Friday night when there is a Level 1 out of 5 severe weather risk for large hail in north-central Minnesota.

DISCUSSION

Issued at 222 PM CDT Wed Jul 22 2026

Rest of Today - Tonight:

Despite high pressure over the region today, partly cloudy to mostly cloudy skies persist across much of the Northland this afternoon into early evening, with the highest coverage in the Arrowhead and northwest Wisconsin. High temperatures this afternoon top out in the low to upper 70s along with dry conditions. Winds become calm to light tonight with comfortable low temperatures in the upper 40s in north-central Wisconsin to 50s elsewhere. Some hazy skies return starting tonight for portions of the area as wildfire smoke from out west inches back into the Northland.

Late this Week - Early Next Week:

The upper-level pattern across the CONUS remains amplified late this week into early next week as a mid/upper-level ridge axis over the western CONUS broadens and general troughing occurs over eastern Canada and the eastern CONUS. This pattern will leave the Upper Midwest in general northwest flow aloft, through which periodic shortwave troughs traversing the flow will produce shower and thunderstorm chances at times for portions of the Northland.

The first round of precipitation would be a 10-20% chance in far northern Minnesota near the International Border for isolated showers Thursday morning, but a slightly better chance (20-30%) for isolated showers/non-severe storms Thursday afternoon and evening. The area of rain potential has been trending slightly farther north. Very limited rainfall amounts are expected with this first round, mostly 0.10" or less unless a thunderstorm moves through, in which case very localized amounts to 0.25" cannot be ruled out.

The best rain chances (30-90%; highest for the Iron Range, Arrowhead, and areas north) would be with a second shortwave trough and attendant surface cold front late Friday afternoon into Saturday morning. Forecast rainfall amounts with these scattered showers and thunderstorms are mostly 0.2-0.5" north of the Iron Range, 0.1-0.2" for the Iron Range, and 0.1" or less south of the Iron Range. The probabilities for localized amounts >0.5" are only 20-40% in far northern Minnesota. Strong to severe storms (Level 1 out of 5) are possible along and near the cold front in north-central Minnesota late Friday afternoon into Friday night with instability (MUCAPE 1000-1500 J/kg) and deep shear profiles (35-50 kt) favoring elevated supercell structures. as there may be some weak capping that hangs around. If storms stay elevated, this would favor large hail (up to quarter to ping pong ball size) as the primary severe threat, though a secondary threat of damaging wind gusts to 60 mph couldn't be ruled out if the storms can become surface based.

Depending on how quickly the cold front moves southeast through the Northland on Saturday, there is a lower chance (10-20%) that storms could redevelop Saturday afternoon along and ahead of the cold front in portions of northwest Wisconsin and be capable of strong to severe storms with large hail and damaging winds as the main threat. However, the forecast trend with this cold front has been speeding up its exit to the east of northwest Wisconsin Saturday afternoon, so the more likely scenario is that storms do not occur at all there Saturday PM.

There are additional, sporadic shower and thunderstorm chances (10-40%) for Sunday into Monday, but confidence remains low regarding location and precipitation potential due to uncertainty in how far south any shortwave troughs rounding the top of the mid/upper-level ridge can get into the Northland and model soundings showing a fairly stout capping inversion for most of the Northland both days. Should the area become uncapped, both Sunday and Monday could see conditional, low- confidence strong to severe storm potential. Overall, the synoptic pattern through at least early next week does not favor any notable, widespread precipitation.

Hot conditions and potential Heat Advisories for portions of the Northland return by this weekend into early next week. High temperatures gradually warm from the low to mid 80s on Thursday to mid-80s to low 90s on Saturday through Monday, though onshore flow/lake breeze on Sunday would likely keep the hottest conditions away from Lake Superior and the Arrowhead. These hotter conditions combined with fairly low relative humidity and breezy conditions at times could lead to a return of elevated fire conditions for Friday into early next week.

Beyond Early Next Week:

Warmer than normal temperatures are favored for the end of July into very early August, as well. This is highlighted by the CPC 8-14 day temperature outlooks and ensemble guidance, mainly due to persistence of the mid/upper-level ridge over the western to central CONUS.

AVIATION /00Z TAFS THROUGH 00Z THURSDAY/

Issued at 620 PM CDT Wed Jul 22 2026

Scattered, diurnal cumulus with bases at 6 to 7 kft as of issuance time to slowly decrease in coverage this evening, leaving us with clear to mostly clear skies overnight tonight. Some smoke begins to work back into the region from the west starting tonight, but no reductions in visibility are expected. Another day of deeper low-level mixing and VFR conditions expected for Thursday. There is a 10-20% chance for a few showers near KINL roughly 11-15Z Thursday morning, but better potential stays north of the International Border until Thursday afternoon/evening when additional isolated showers and storms (10-30% chance) are once again possible near KINL and far northern Minnesota near the International Border. Northwest to west winds becoming light and variable to calm tonight. Winds increase out of the southwest on Thursday with daytime gusts of 14-18 kt, strongest in the afternoon in northern Minnesota.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 222 PM CDT Wed Jul 22 2026

No additional changes were made to the Small Craft Advisory for Taconite Harbor to Grand Portage for mid-afternoon into evening with southwest winds up to 20-25 kt along with 1 to 3 foot waves. Southwest winds decrease to 5 to 15 knots tonight, then gusts pick back up to 15 to 25 knots for daytime Thursday, the strongest of which are favored in the Outer Apostle Islands and Silver Bay to Grand Portage along with 3 to 4 ft waves near Grand Portage. Additional Small Craft Advisories will likely be needed. Stronger southwest winds develop for Friday Saturday morning across much of western Lake Superior nearshore waters, likely leading to more hazardous conditions for small craft. There is a 20-30% chance for gale-force winds near Grand Portage Friday night as well as scattered thunderstorms, with the main storm threat being cloud-to-water lightning.

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

FIRE WEATHER

Issued at 222 PM CDT Wed Jul 22 2026

High pressure the rest of today and tonight keeps conditions rain-free conditions with afternoon highs in the 70s and minimum RH values of 30 to 40% along with partly to mostly cloudy skies with mixing heights of 5000-7000 ft. RH recovers to 80-95% across most of the Northland tonight.

There is a 10-20% chance for isolated showers Thursday morning in far northern Minnesota near the International Border and a 20-30% chance for a few showers and general thunderstorms in the same area Thursday afternoon and evening. Precipitation amounts will be 0.10 inches or less, though very localized amounts to 0.25" cannot be ruled out for anywhere that a thunderstorm moves overhead. Minimum RH on Thursday again dips to 30 to 40% along with high temperatures in the low to mid 80s and southwest winds of 5-10 mph with daytime gusts of 15-20 mph. RH recovers above 75-80% again Thursday night.

A cold front late Friday into early Saturday brings better precipitation chances (30-90%, highest along and north of the Iron Range). Forecast rainfall amounts with these scattered showers and thunderstorms are mostly 0.2-0.5" north of the Iron Range, 0.1-0.2" for the Iron Range, and 0.1" or less south of the Iron Range. The probabilities for localized amounts >0.5" are only 20-40% in far northern Minnesota. Portions of north-central Minnesota could also see a few strong to severe storms with large hail and frequent lightning late Friday and Friday night. Otherwise, no significant rain chances are expected through this weekend into early next week. Temperatures warm back into the 80s and 90s for the weekend into Monday with breezy conditions possible both Friday and Saturday that, when combined with the heat and fairly low RH of 35-45% for much of the Northland, could bring about a return of elevated fire weather conditions.

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

DLH WATCHES/WARNINGS/ADVISORIES

MN...None. WI...None. MARINE...Small Craft Advisory until 10 PM CDT this evening for LSZ140- 141.