textproduct: Duluth

KEY MESSAGES

- Extreme heat continues today across the area with temperatures in the 90s to near 100F. Another round of excessive heat is likely Tuesday.

- Critical fire weather is expected again today for portions of north-central and northeast Minnesota with dry afternoon relative humidity and gusty southwest winds. Another round of critical fire weather is possible Tuesday.

- Next best chance for precipitation late this week.

UPDATE

Issued at 253 AM CDT Mon Jul 13 2026

We remain trapped under the influence of a stout upper level high pressure today. With 2AM temperatures still in the 70s across the Northland (outside of some areas right along Lake Superior on the North Shore), today will provide little to no relief from the ongoing heat wave. Guidance continues to point towards today being the hottest day of the heat event. High temperatures could touch or even exceed 100F for the Borderlands in Koochiching, northern St. Louis, and inland Lake/Cook Counties while high temperatures in the 90s are expected across the rest of the Northland. An Extreme Heat Warning continues through the day for the entire area except Price County. The Extreme Heat Warning for areas along and south of Hwy 2 in MN and everywhere in NW WI except Price County has been extended through Tuesday evening due to another very warm night and afternoon expected in those areas. Once the warning expires for the areas north of Hwy 2 in MN, a Heat Advisory will likely be needed at least through Tuesday evening there. In Price County, the Heat Advisory has been extended to run through at least Tuesday evening. A Heat Advisory may be needed along our southern tier of counties for Wednesday. One small note of uncertainty: there has been significant upwelling of cold water in Lake Superior from Duluth to Two Harbors due to the southwest winds over the last 24 hours. This could affect temperatures today very close to the lake, similar to the extremely tight temperature gradient we have seen further up the North Shore. For now, have opted to stay on the hotter side for much of the forecast.

Today will be another day of very concerning fire weather conditions in northern Minnesota. The extreme heat, along with slightly lower dewpoints along the International border, should combine to create afternoon relative humidity values of 20-30% in the borderlands. This will combine with gusty southwest winds of 10-15mph, gusting as high as 30mph. There is a 35-40mph low level jet expected to translate over NE MN today, so some slightly stronger gusts could occasionally mix down this afternoon. A Red Flag Warning is in effect for much of north-central and northeast Minnesota today. Tuesday, another dry day is in store for the Borderlands. Winds shouldn't be as strong Tuesday, but will be turning with a passing cold front, gradually becoming northwesterly through the day, and some gusts of 15-20mph are possible with that dry front. A Fire Weather Watch is in effect for portions of northern Minnesota for Tuesday.

Following a mostly dry cold front sagging down into the area Tuesday afternoon into Wednesday, we should see temperatures back off slightly, along with dew points falling into the 50s. Afternoon high temperatures in the 80s are still likely through the week as we stay on the periphery of upper level ridging. That cold front Tuesday could bring some increased clouds to the area and some guidance is suggesting it may be able to pop off some very isolated showers and thunderstorms in the evening, along the gradient of upper level capping. However, drier air in the low levels and overall weak forcing has kept us from adding any PoPs into this time period for now. The next best chance for any precipitation still looks like the potential from an upper level shortwave moving across the northern portions of the area sometime Thursday-Friday.

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 /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 1226 AM CDT Mon Jul 13 2026

VFR conditions continue through the TAF period. Some LLWS is possible at HIB and INL overnight as strong winds continue aloft. Gusty southwest winds return for all terminals through the morning after sunrise.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 253 AM CDT Mon Jul 13 2026

Strong southwest winds 10-15kts with gusts 20-30 knots are expected across Western Lake Superior today, with the highest winds along the North Shore from Grand Marais to Grand Portage, where some localized gale-force gusts are possible. There has been some notable upwelling of colder water temperatures in the Twin Ports and North Shore over the last 24 hours. It is uncertain whether or not this will create a shallow stable layer for those areas, preventing the strongest gusts from mixing down. At this point, have aired on the side of stronger gusts making it to the surface today, and issued a Small Craft Advisory for most of the nearshore waters, other than Chequamegon Bay to Saxon Harbor. While most zones should see winds calm through the evening, advisories remain in effect overnight for the Outer Apostle Islands and nearshore waters from Grand Marais to Grand Portage where it will take a little longer for winds and waves to calm down. Winds largely stay out of the southwest Tuesday, but should gradually calm down through the day, with a switch to northwest winds Tuesday evening into Wednesday morning. Wednesday, expecting fairly light, mostly onshore winds. The chance for any precipitation is low over the next couple of days. With dewpoints remaining fairly high, it would not be out of the question to see some locally dense marine fog form at times.

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

FIRE WEATHER

Issued at 253 AM CDT Mon Jul 13 2026

Critical fire weather conditions continue for portions of the area today, with very hot afternoon temperatures, minimum relative humidity of 20-40%, and a strong southwest wind. The worst conditions are expected in north-central and northeast Minnesota where a Red Flag Warning is in effect. Gusts of 15-30mph are expected this afternoon, and its possible that some areas along the Canadian Border could see occasional localized gusts up to 35mph. In that same area, we could see afternoon temperatures exceed 100F and relative humidity drop to near 20%. A mostly dry cold front is expected Tuesday, which will minimally reduce some of the very hot temperatures and lead to a wind switch from southwest to northwest through the day. That wind switch is expected to translate from north to south Tuesday, with some gusts of 15-20 mph possible along the front. Again, afternoon relative humidity of 20-40% possible Tuesday. A Fire Weather Watch is in effect for far northern portions of the area Tuesday.

At this time, little to no precipitation is expected with that cold front Tuesday. There is a small (<10%) chance for isolated showers and thunderstorms, which may lead to some small pockets of potential dry lightning. The next best chance of any precipitation is not until the end of this week, and exact timing, placement, and rainfall amounts are still uncertain.

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

CLIMATE

Issued at 253 AM CDT Mon Jul 13 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 High Temperatures:

July 13 Forecast KINL: 93/1983 99 KHIB: 92/1983 95

July 14: KDLH: 98/1901 95 KHIB: 95/1983 93 KASX: 94/1980 98

Record High Minimum Temperatures:

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

July 14: KDLH: 75/1983 72 KINL: 70/1983 68 KBRD: 72/1901 69 KHIB: 69/1995 69 KASX: 75/1983 73

DLH WATCHES/WARNINGS/ADVISORIES

MN...Extreme Heat Warning until 9 PM CDT this evening for MNZ010>012-018>021-026. Red Flag Warning from 11 AM this morning to 10 PM CDT this evening for MNZ010>012-018>021-025-026-037. Fire Weather Watch from Tuesday afternoon through Tuesday evening for MNZ010>012. Extreme Heat Warning until 7 PM CDT Tuesday for MNZ025-033>038. WI...Extreme Heat Warning until 7 PM CDT Tuesday for WIZ001>004- 006>008. Heat Advisory until 9 PM CDT Tuesday for WIZ009. MARINE...Small Craft Advisory from 11 AM this morning to 6 AM CDT Tuesday for LSZ140. Small Craft Advisory from 1 PM this afternoon to 9 PM CDT this evening for LSZ141>143-146-147. Extreme Heat Warning until 9 PM CDT this evening for LSZ142. Small Craft Advisory from 3 PM this afternoon to 7 PM CDT this evening for LSZ144-145. Small Craft Advisory from 1 PM this afternoon to 6 AM CDT Tuesday for LSZ150.