textproduct: Duluth

KEY MESSAGES

- Hot temperatures last through Monday, and heat headlines are in effect.

- The heat combined with dry and windy conditions is leading to dangerous fire weather conditions. There is little precipitation in the forecast to ease the fire concerns.

- Next chance for showers and storms (30%) will be late this week

DISCUSSION

Issued at 1235 PM CDT Sun Jul 12 2026

For the rest of this afternoon and tonight, dangerously hot and humid conditions will envelope the Northland. High temperatures are climbing into the 90s, with some locations approaching triple digits. An Extreme Heat Warning is in effect for most of the area, while a Heat Advisory covers Price County. Initial chances for afternoon showers and thunderstorms have decreased, with any development expected to stay well to the east of our region. Overnight lows will remain unseasonably warm in the upper 60s and 70s.

On Monday, the extreme heat continues with temperatures again increasing into the 90s and triple digits. This intense heat will combine with stronger southwest winds gusting up to 20 to 30 mph and low relative humidity values down to 22 percent to create widespread critical fire weather conditions. A Fire Weather Watch is in effect for much of northeast Minnesota. Additionally, marine fog is forecast to linger or return across Lake Superior, which may necessitate further dense fog advisories along the North Shore. A dry, weak cool front will drop from north to south late Monday night into Tuesday morning, bringing a shift to westerly winds and lower dewpoints that will begin to relieve the oppressive heat, especially across our northern areas.

The area will stay locked into this ridge pattern for the better part of the week. Wednesday will bring a break from the intense humidity as temperatures settle back into the 80s for most locations, though areas immediately adjacent to Lake Superior will experience cooler conditions due to an inland- moving lake breeze. Dry conditions will generally prevail during the day on Wednesday.

The next opportunity for precipitation arrives mid-to-late week as a shortwave atmospheric disturbance rides the ridge into the Northland. This system will interact with elevated instability between 2000 and 3000 J/kg and sufficient wind shear of 30 to 40 knots, creating an environment capable of producing strong to severe storms from Thursday into Friday. However, a strong cap in the low levels will inhibit surface-based storm development, meaning elevated thunderstorms will be the primary threat. Scattered showers and storm chances linger into Saturday, with daily high temperatures remaining seasonal in the 80s.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/

Issued at 631 PM CDT Sun Jul 12 2026

VFR conditions through the forecast. Mostly clear skies with upper level clouds returning in the latter portions of the forecast. Winds will taper off early in the period with low level wind shear overnight for INL/HIB. Tomorrow, expect windier conditions with gusts out of the southwest around 20-25 kts.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 1235 PM CDT Sun Jul 12 2026

Marine dense fog over Lake Superior is reducing visibilities significantly, oscillating quickly between the shore and further out in the lake. A Dense Fog Advisory is in effect until 6 PM this evening for nearshore zones from Grand Portage to Duluth. Models hint at fog either lingering or returning for Monday, and additional fog advisories may be needed. A Small Craft Advisory is active until 10 PM Sunday from Grand Portage to Grand Marais and across the Apostle Islands for southwest winds gusting up to 25 knots and waves up to 4 feet. On Monday, southwest winds will increase to 20 to 25 knots with gusts up to 30 knots, building waves to 4 to 6 feet, with occasional heights to 8 feet in the northeastern nearshore waters. Additional small craft headlines will be needed. Winds do approach gale criteria, but gales are not expected at this time.

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

FIRE WEATHER

Issued at 1235 PM CDT Sun Jul 12 2026

Hot temperatures continue across the Northland, with high temperatures in the 90s and some areas could reach triple digits. An Extreme Heat Warning is in effect through Monday.

A Red Flag Warning is active until 9 PM this evening north of the Iron Range for southwest winds of 10 to 15 mph, gusts up to 25 mph, and minimum relative humidity values around 25 to 35 percent. Winds are expected to remain elevated at 10-15 mph overnight tonight.

A Fire Weather Watch is in effect for Monday across a larger area of northeastern Minnesota as southwest winds increase, gusting up to 20 to 30 mph, while relative humidity drops further to 22 to 35 percent.

The worst conditions will be in an area under Abnormally to Severe drought conditions and have seen little rainfall the past few weeks.

Winds shift to the west/northwest and decrease to 5 to 10 mph on Tuesday following a dry frontal passage. Temperatures will also decrease back into the 80s for the second half of the week, but minimum RHs will remain in the 25-45% range daily.

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

CLIMATE

Issued at 106 AM CDT Sun Jul 12 2026

Daily high temperatures and daily record warm low temperatures are forecast over the next few days at select Climate sites in the Northland. The current temperature record and year it was observed are in the first column, with the current forecast temperature in the second column.

Site Identifiers and Names KDLH: Duluth Area (measured at Duluth Int'l Airport) KINL: International Falls area (measured at Int'l Falls Airport) KHIB: Hibbing area (measured at Range Regional Airport) KBRD: Brainerd area (measured at Brainerd Regional Airport) KASX: Ashland area (measured at JFK Memorial Airport)

Record Daily High Temperatures:

July 12: Forecast KINL: 96/1921 99 KHIB: 91/1969 95

July 13: KINL: 93/1983 100 KHIB: 92/1983 96

July 14: KASX: 94/1980 96

Record Daily Warm Low Temperatures:

July 12: Forecast KDLH: 70/1892 71 KINL: 69/1898 71 KHIB: 67/1942 69 KASX: 67/2018 70

July 13: KINL: 69/2013 72 KBRD: 73/1936 72 KHIB: 67/1997 70 KASX: 73/1954 71

July 14: KDLH: 75/1983 72 KINL: 70/1983 69 KBRD: 72/1901 71 KHIB: 69/1995 70

DLH WATCHES/WARNINGS/ADVISORIES

MN...Extreme Heat Warning until 1 AM CDT Tuesday for MNZ010>012- 018>021-025-026-033>038. Fire Weather Watch from Monday morning through Monday evening for MNZ010>012-018>021-025-026-037. Red Flag Warning until 9 PM CDT this evening for MNZ010>012- 018-019. WI...Extreme Heat Warning until 1 AM CDT Tuesday for WIZ001>004- 006>008. Heat Advisory until 1 AM CDT Tuesday for WIZ009. MARINE...Small Craft Advisory until 10 PM CDT this evening for LSZ140- 146-147-150. Extreme Heat Warning until 1 AM CDT Tuesday for LSZ142.