textproduct: Duluth

KEY MESSAGES

- Showers and thunderstorm chances again this afternoon and evening, with isolated severe storms possible. Primary hazards from thunderstorms will be damaging winds and heavy downpours/localized flooding.

- Gusty northeast winds off of Lake Superior today will lead to a high risk of rip currents along Minnesota and Wisconsin Point beaches.

- Slightly cooler this weekend, and then hotter temperatures return for the work week. Additional shower and thunderstorm chances next week.

UPDATE

Issued at 338 AM CDT Sat Jul 4 2026

Most showers and thunderstorms have dissipated across the Northland early this morning, but overall precipitation chances are not done yet. The area stays at the bottom of an omega block across Canada today, in the zonal flow beneath a high pressure to our north. A weak shortwave prompts a surface low propagating west to east to our south today, while a bigger upper level trough over British Columbia and the Canadian Rockies throws out a cold front extending down to our area from Lake Winnipeg into north-central MN. This should pull a tongue of moisture (PWATs around 1.5" and dewpoints in the upper 60s) and instability into the Northland, primarily away from Lake Superior. As some of those weak mid to upper level forcings propagate through the zonal flow, we do expect another round of afternoon and evening thunderstorms to pop up today. Before that, some isolated sporadic cells could pop here and there. Any outflow boundaries from morning precipitation could act as a surface forcing mechanism for afternoon storms. Similar to the past couple of days, wind shear is expected to be minimal, so storms will be likely be in the form of messy clusters that are dependent on very small scale forcing and influences. We could see some isolated severe storms today (Marginal Risk, level 1/5), with the primary hazard expected to be damaging wind gusts as the cores of storms collapse with spunky outflows. We could also see some appreciable rainfall amounts out of these storms, with the HREF max and LPMM products suggesting very localized totals of 3"+, location dependent on exactly where storms fire. Many model solutions however are suggesting that some of the highest precipitation totals could be in the Itasca/Cass/Aitkin county to I-35 and Twin Ports area, which is where some of the highest localized rainfall totals have been recently. If heavy rains fall in the right area, some localized flooding could be possible. The primary timing for widespread storms and any severe risk should be between 3-10pm.

Temperatures today should actually be on the relatively cooler side with highs in the 70s, except in the 60s to high 50s near Lake Superior. Those much cooler coastal temperatures will be thanks to a breezy northeasterly wind off the big lake. That is expected to push some bigger waves into the Twin Ports leading to a high risk of rip currents along Minnesota and Wisconsin Point beaches. A Beach Hazards Statement is in effect.

A couple more showers and thunderstorms could be possible in NW WI Sunday as the upper level shortwave propagates east, but some of that activity will likely be tied to where and when storms develop this evening, with a downstream outflow influence possible. Models are in decent agreement that we should get a largely inactive 18 hours or so late Sunday evening into Monday. However, as high pressure pushes back into the Central Plains and lower Midwest, we'll find ourselves in the area of opportunity for ridge running disturbances late Monday into Tuesday as the chance of precipitation returns. That high pressure will also bring widespread heat back to the Northland with highs in the mid to upper 80s Monday and Tuesday.

DISCUSSION

Issued at 307 PM CDT Fri Jul 3 2026

High pressure was located both to the north and south of the Northland across northern Manitoba and the Ohio Valley. A stationary boundary was analyzed between these areas of high pressure from the Upper Peninsula of Michigan into northern Minnesota and South Dakota. A lake breeze was evident on radar along the South Shore of Lake Superior into far northwest Wisconsin. As instability builds this afternoon, isolated to scattered showers and thunderstorms are expected to develop across the region in the vicinity of the stationary boundary and possibly the lake breeze. Latest RAP analysis shows around 1500-3000 J/kg of CAPE in the Brainerd Lakes with effective shear less than 25 knots. RAP forecasts show shear becoming marginally better by around 00z, but still only around 25 to 30 knots. This will favor clusters of storms and pulse updrafts. With DCAPE of around 1000 J/kg, damaging wind gusts to around 50 to 60 knots look to be the primary threat with any storms. Some hail will also be possible with pennies being the most likely max, but a few reports of quarters cannot be ruled out given the strong instability in place.

As for timing and coverage of showers and storms through tonight, have leaned on the HRRR as a base and then adjusted from there. CAMs have not been doing well in this weakly forced regime, but most break out activity across the northern half of Minnesota in roughly the same time frame. Satellite shows cumulus bubbling across the region as of the time of this writing with some radar returns across central Minnesota, which is around an hour or so sooner than what the CAMs indicate. With the bulk of the instability centered across the Brainerd Lakes area, SPC has pulled the Marginal Risk area out of northwest Wisconsin and focused it across north-central Minnesota.

Convective evolution for overnight into Saturday remains in question given the weakly forced nature. However, better forcing looks to arrive through the day as an upper level shortwave moves in overhead while developing low pressure passes to the south. This may lead to more in the way of coverage for showers and storms through the day and into the evening hours. With a lot of uncertainty in place, trended POPs back towards the NBM for Saturday. This has led to a slight uptick in POPs with this package, mainly across southern areas closer to the developing low. Widespread cloud cover may limit instability and shear remains rather anemic, so no strong or severe storms are currently expected. If there is more sun during the morning and early afternoon, a few stronger storms cannot be ruled out. Additionally, with high pressure to the north and the developing low to the south, a tightening pressure gradient will set up across western Lake Superior and funnel easterly winds into the western arm of the lake. This will lead to an increased risk of rip currents along the beaches of Duluth and Superior. This will also push a lake breeze inland with 60s expected near the lake and into the Nemadji Valley with 70s and lower 80s elsewhere.

Surface high pressure will try and build in on Sunday, but an upper trough will remain in place which will keep chances for showers and a few thunderstorms in place. Temperatures will start to warm again with highs in the 70s and 80s. High pressure may keep dry conditions in place for Monday as temperatures further warm into the 80s. Rain chances then return for Tuesday into Thursday with temperatures remaining in the 70s and 80s.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 612 AM CDT Sat Jul 4 2026

Mostly VFR early this morning, with some lingering fog at HYR, which should burn off quickly. Expect some gusty easterly winds at DLH, with southeast to northeast winds up to 10 knots elsewhere through the day. Another round of afternoon and evening thunderstorms are possible today, with the best chances at all terminals except DLH. Some storms may be capable of producing damaging winds, up to penny sized hail, and heavy downpours. Precipitation chances should wane through the evening. Another slight chance for some rain showers at HYR going into Sunday morning.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 338 AM CDT Sat Jul 4 2026

Northeast winds continue through the weekend, with the highest gusts expected this afternoon. Gusts of 15-25 knots are possible, highest in the Twin Ports and in the Outer Apostle Islands. In those aforementioned areas, waves of 2-4 feet are possible. A Small Craft Advisory is in effect. Northeasterly winds continue Sunday but shouldn't be as strong. There is a very slight chance for some thunderstorms to make it to the nearshore waters this evening, with the best chance from the Twin Ports to the South Shore. Monday, southerly winds return with additional precipitation chances.

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

FIRE WEATHER

Issued at 338 AM CDT Sat Jul 4 2026

Slightly cooler temperatures this weekend before hot temperatures return for the work week. Today, another round of afternoon showers and thunderstorms is possible, with the best chance away from Lake Superior and the far MN Arrowhead. Isolated severe storms are possible, with the primary hazard being damaging winds. Some lingering showers and storms could persist into Sunday, especially in inland NW WI, but no severe weather is expected. Locally excessive rainfall is possible, but it will be very hit and miss. Winds should be fairly light through the weekend away from Lake Superior. Near the big lakes some blustery easterly winds are possible today and tomorrow. Southerly winds return Monday.

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

DLH WATCHES/WARNINGS/ADVISORIES

MN...Beach Hazards Statement from noon CDT today through this evening for MNZ037. WI...Beach Hazards Statement from noon CDT today through this evening for WIZ001. MARINE...Small Craft Advisory from noon today to 7 PM CDT this evening for LSZ144-145. Small Craft Advisory from 2 PM this afternoon to 7 PM CDT this evening for LSZ150.