textproduct: Duluth

KEY MESSAGES

- Hot and muggy conditions today through Monday and possibly into Tuesday. Heat Advisories are in place today with widespread Extreme Heat Warnings for Sunday and Monday.

- Low chances for showers and thunderstorms this afternoon and tonight, mainly across the Borderlands.

- Dry conditions will prevail through the forecast period with minimal rainfall chances. The heat and dry conditions may lead to fire weather concerns across northern Minnesota Sunday through Tuesday.

DISCUSSION

Issued at 204 PM CDT Sat Jul 11 2026

High pressure stretched from James Bay into the Central Plains early this afternoon with a trough analyzed across northwestern Minnesota from an area of low pressure in central North Dakota. A few isolated thunderstorms were seen on radar earlier across western Koochiching County. Temperatures will warm into the 80s and 90s across most of the Northland this afternoon with 70s and lower 80s along the North Shore. Mainly dry and humid conditions are expected to prevail through the afternoon. A few isolated showers and thunderstorms will be possible across the Borderlands this afternoon into this evening, but overall confidence on this is low with weak forcing in place. Convective temperatures will be in the upper 80s with CAPE around 2000-3000 J/kg in this area. With air temperatures rising into the upper 80s and lower 90s, this will likely be the mechanism for storms. Small hail and gusty winds will be the main threats with winds likely being driven by collapsing cores.

Heading into tonight, there are some hints for overnight convection in the northwest flow regime aloft. Weak forcing continues to be an issue and leads to lower confidence in the development of storms. Some CAMs hint at the development of showers and storms, but the 12z runs are less optimistic than the 00z runs. CAMs tend to struggle in weakly forced regimes, so the drier route seems more likely with a lack of a defined forcing mechanism.

Dangerous heat conditions are then expected for Sunday and Monday as temperatures reach into the 90s over most of the Northland with dewpoints in the 60s and 70s leading to hot and muggy conditions. With widespread Wet bulb globe temperatures in excess of 83F and Heat Risk in the Major category, the Extreme Heat Watch has been upgraded and expanded to an Extreme Heat Warning with this forecast package. Areas along the North Shore will likely not see much relief for the heat aside from locations immediately adjacent to Lake Superior. Have kept Price out of the warning for now due to lower forecast WBGTs and placed them in an Advisory, but they may need to be added for Monday. Little relief is expected for Sunday night into Monday with low in the upper 60s and 70s with continued muggy conditions.

Near-critical fire weather conditions will also be possible across the Boundary Waters into the Arrowhead Sunday and Monday as well. Southwesterly winds will gust to 20 to 25 mph in this area with dewpoints falling into the 25-30% range, especially on Monday. Fire Weather headlines may be needed with these conditions in place. There are low chances for isolated showers and storms each afternoon, but the hot temperatures will likely keep activity from developing with capping aloft. Should anything develop Sunday afternoon, storms may be strong to severe with wind gusts to 60 mph and hail up to ping pong ball size possible with sufficient shear to support supercells.

A cold front is expected to push from north to south across the region Tuesday into Tuesday night. This will likely be a dry frontal passage, but it will push the low-level moisture to our south. Highs Tuesday will again reach into the upper 80s and 90s with dewpoints in the 60s ahead of the front. Heat headlines may need to be extended into Tuesday. Temperatures cool slightly for Wednesday through Friday, especially near Lake Superior where the lake breeze is expected to push inland. Highs will be in the 80s and low 90s away from Lake Superior with 70s and lower 80s near the lake. Dewpoints will also be in the 50s to lower 60s during this time, so it will feel significantly less muggy. Northwest flow aloft will bring periodic waves through the Upper Midwest during this time and may lead to isolated showers and storms, but no large organized systems are expected.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1224 PM CDT Sat Jul 11 2026

VFR conditions are expected to prevail through the period. Chances for isolated showers and thunderstorms have lowered, so have removed any mention at DLH. Southwesterly winds are expected to increase Sunday morning with gusts to 15 to 20 knots expected.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 204 PM CDT Sat Jul 11 2026

Winds will be variable this afternoon at around 10 knots or less, aside from near Grand Portage where southerly winds of 5 to 15 knots are expected. Southwesterly winds of 5 to 15 knots will be in place for Sunday with gusts to 20 knots from Grand Marais to Grand Portage. Heading into Monday, southwesterly winds continue at 10 to 20 knots with gusts to 25 knots near Grand Portage. A Small Craft Advisory may be needed for that zone Monday into Monday evening.

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

FIRE WEATHER

Issued at 252 PM CDT Sat Jul 11 2026

Very warm temperatures today are expected to trend even warmer tomorrow as a ridge of high pressure continues to build and southwest winds bring in hot temperatures. A Heat Advisory remains in effect until this evening across much of the area. For Sunday through Monday, an Extreme Heat Warning is in effect for most as high temps increase to the 90s to 100 degrees with elevated dewpoint temperatures.

After fuels collaboration with Predictive Services, a Fire Weather Watch has been issued for portions of northeast Minnesota on Sunday and Monday. While min RH on Sunday will be in the 26-35% range within the Fire Weather Watch area, the exceptional heat, current fuel conditions, and breezy southwest winds gusting up to 20-25 mph will cause elevated fire concerns.

On Monday, southwest winds will be trending similar in northern Minnesota ahead of an approaching dry cold front. Min RH on Monday will be trending slightly lower, as low as 23% across much of the BWCA. An upgrade of the current Fire Weather Watch to a Red Flag Warning will most likely be needed on Monday, where confidence in critical fire weather conditions is higher. Additional fire weather headlines will likely be needed on Tuesday in the Borderlands and MN Arrowhead following the dry cold frontal passage late Monday night into Tuesday morning.

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

CLIMATE

Issued at 204 PM CDT Sat Jul 11 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 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 11: Forecast KINL: 94/1921 92 KHIB: 89/1970 87

July 12: KINL: 96/1921 98 KHIB: 91/1969 95

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

July 14: KASX: 94/1980 95

Record Daily High Minimum Temperatures:

July 12: Forecast KINL: 69/1898 69 KHIB: 67/1942 67 KASX: 67/2018 66

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

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

DLH WATCHES/WARNINGS/ADVISORIES

MN...Extreme Heat Warning from 11 AM Sunday to 1 AM CDT Tuesday for MNZ010>012-018>021-025-026-033>038. Heat Advisory until 9 PM CDT this evening for MNZ010>012-018- 019-025-026-033>038. WI...Extreme Heat Warning from 11 AM Sunday to 1 AM CDT Tuesday for WIZ001>004-006>008. Heat Advisory until 9 PM CDT this evening for WIZ001-002-006- 007. Heat Advisory from 11 AM to 9 PM CDT Sunday for WIZ009. MARINE...Extreme Heat Warning from 11 AM Sunday to 1 AM CDT Tuesday for LSZ142.