textproduct: Duluth

KEY MESSAGES

- A High Risk for rip currents continues today for the beaches around the Twin Ports. Expect dangerous swimming conditions through this evening due to high waves.

- Showers and thunderstorms are likely to arrive this evening, continuing through tonight. Severe thunderstorms are not anticipated, although a strong storm or two in north-central MN capable of producing sub-severe hail is possible.

- Monday is trending dry, with the majority of the Northland remaining dry through Wednesday. High temps will be warm in the upper 70s to mid 80s for most.

- Additional chances for rain arrive later in the week with temperatures remaining unseasonably warm.

DISCUSSION

Issued at 251 PM CDT Sun Aug 30 2026

Mostly cloudy skies are occurring this afternoon across most of the area with isolated light rain showers occurring ahead of an approaching warm front and associated low pressure. Dewpoint temps and PWAT will be increasing this afternoon and evening as the warm front continues to lift north, with dewpoints in the mid 60s to low 70s by this evening. As a lobe of vorticity at 500mb associated with the vertically-stacked low pressure over the Canadian Prairies propagates through the CWA tonight into Monday morning, this will likely (50-75% chance) bring showers and thunderstorms to the area.

Previous forecasts indicated a potential for isolated severe thunderstorms in north-central MN as this warm front lifted north. However, recent hi-res models runs have reduced the severe potential to the point where severe thunderstorms are not anticipated in the Duluth CWA this evening through tonight. While MUCAPE values will likely be increasing to an impressive 2,000 J/kg overnight into early Monday morning, this instability is unlikely to be realized. A substantial low-level cap will increase sfc-based CIN up to 400 J/kg and dry air in the low to mid levels will likely inhibit severe convection. With this being said, a strong thunderstorm capable of producing up to nickel sized hail will still be possible with gusty winds of 50 mph or less being a secondary concern given the capping.

On Monday, an occluded front is anticipated to sweep through the CWA. This will bring a wind shift with the breezy easterly winds today, which have been causing dangerous swimming conditions around the Twin Ports, switching to the west. Despite MUCAPE values remaining elevated through Monday morning into the early afternoon, significant capping and dry air entrainment in the low to mid levels is currently anticipated to keep things dry in the afternoon. CAMs are all in solid agreement for minimal to no precipitation development along the occluded front on Monday, so kept the forecast dry.

As the vertically-stacked low pressure propagates east-northeast towards Hudson Bay on Monday into Wednesday, this will place the CWA in a fairly benign pattern with a mid-level ridge building. The bulk of precipitation associated with a shortwave lifting north from the High Plains on Tuesday night into Wednesday will likely remain just south of the CWA. Southern portions of the WI CWA has an up to 30% chance for scattered showers and thunderstorms, with QPF progged to be on the light side at a few hundredths of an inch. Elsewhere, dry conditions are forecast on Monday through Wednesday with unseasonably warm temps.

Additional chances for showers and thunderstorms arrive Thursday and continue on and off into the weekend as a series of shortwaves potentially propagate through the area. Signals for decent precipitation are not particularly strong, with most global ensemble members for 24 hour QPF showing relatively light amounts under 0.5" late in the week. Temperatures remain on the warm side for the latter half of the week into next weekend, with highs generally in the upper 70s to mid 80s. Certainly a warm start to September!

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1257 PM CDT Sun Aug 30 2026

IFR to VFR conditions are being observed early this afternoon with isolated light rain showers lifting north into the Arrowhead and far north-central Minnesota. The general trend will be a brief period of higher cigs for several terminals before IFR to LIFR cigs return this evening into tonight. Scattered showers and thunderstorms arrive ahead of approaching low pressure, with rainfall most likely in north-central MN into the Arrowhead tonight into early Monday morning. Fog is unlikely as winds are expected to remain elevated through tonight. Expect winds to shift from easterly to westerly on Monday morning following the passage of an occluded front.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 251 PM CDT Sun Aug 30 2026

Northeast winds remain strong today into early Monday morning as low pressure moves into the region and associated surface fronts sweep through. Small Craft Advisories remain in effect for all nearshore waters as gusts of 25 to 30 knots occurs and wave heights of 2 to 5 feet continue. Thunderstorms are possible tonight into early Monday morning as an occluded front moves east. Winds ease below 10 knots by Monday afternoon, quickly shifting around midday. Southwest winds once again increase on Tuesday with gusts of 15 to 25 knots, especially between Grand Marais to Grand Portage. Additional Small Craft Advisories will likely be needed.

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

FIRE WEATHER

Issued at 251 PM CDT Sun Aug 30 2026

A warm front lifting north this evening into tonight will be increasing moisture and bringing a likely chance (50-75% chance) for showers and thunderstorms to the area. The greatest potential for these showers and thunderstorms will be in north-central MN into the Arrowhead, with wetting rains of 0.25" or greater favored. A few storms may become strong tonight into early Monday morning, with small hail, gusty and erratic winds, and lightning being concerns. An occluded front moves through on Monday, which will quickly shift winds from the easterly direction seen today into tonight to the west. The forecast has trended drier for Monday, with moderately dry min RH as low as 35% forecast around the Chippewa NF and Brainerd Lakes area. These moderately dry min RH values shift into northwest WI on Tuesday afternoon. Otherwise, minimal fire weather concerns for the remainder of the forecast period with additional chances for rain arriving late in the week into next weekend.

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

DLH WATCHES/WARNINGS/ADVISORIES

MN...Beach Hazards Statement until 10 PM CDT this evening for MNZ037. WI...Beach Hazards Statement until 10 PM CDT this evening for WIZ001. MARINE...Small Craft Advisory until 9 PM CDT this evening for LSZ121- 148. Small Craft Advisory until 7 AM CDT Monday for LSZ140>142. Small Craft Advisory until 4 AM CDT Monday for LSZ143>145. Small Craft Advisory until 1 AM CDT Monday for LSZ146-147-150.