Marine Weather and Tide Forecast for Superior, WI

DISCUSSION
Issued at 1253 PM CDT Mon Aug 31 2026

Clouds are clearing out from west to east this afternoon as a cold/occluded front passes through. While the air is moist and should become unstable this afternoon ahead of the front, the clouds ongoing right now are likely to inhibit convective initiation in our area. Models have really continued to trend dry this afternoon with thunderstorms possible into the UP and northeast Wisconsin. We will have to keep a keen eye on things this afternoon in case there does happen to be a bit more clearing than expected and storms can initiate further west, but right now confidence is high that northwest Wisconsin will remain dry this afternoon.

Into tonight, nearly vertically stacked low pressure will slowly drift east up in Canada and we will be within the warm sector to the south with quiet (but warm) weather expected tonight into Tuesday. Light winds tonight may result in some fog tonight, but widespread dense fog is not likely. Tuesday afternoon, dry and breezy conditions could result in some elevated fire weather, mainly for northwest Wisconsin.

A quasi-stationary front may develop and produce an area of showers/storms Tuesday night. Models differ on how far north the showers/storms may make it, but east-central Minnesota and northwest Wisconsin have the best chances for rain Tuesday night into Wednesday morning. Not a lot of instability is expected, so severe storms are not expected either.

Wednesday is looking like an "in-between" kind of day with low pressure well to our northeast and ridging off to our west.
Winds will likely be light from approximately the northwest, temperatures will be warm with highs around 80, and clouds may decrease through the day with potentially some drier air moving in.

On Thursday, we may end up in a "dirty ridge" pattern with warm air and moisture advection from the south and potential for a warm front to bring some rain/storm chances in. This sort of unorganized, slightly chaotic pattern underneath a broad ridge looks to continue into the weekend, so look for more occasional shower/storm chances and warm weather. While there are no clear signals for severe weather at this time, it's possible that ingredients could aligns for a few severe storms on some of the days from Thursday into next weekend. Signals for widespread, drought-improving rainfall don't appear imminent, but certainly some places could pick up some decent rain if thunderstorms develop.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/
Issued at 646 PM CDT Mon Aug 31 2026

With the front now moving through the eastern tip of the Arrowhead and northwest WI, VFR conditions prevail at all forecast terminals. Winds are from the southwest to northwest at 4-7kts. Model guidance has backed off fog development overnight, as boundary layer winds remain elevated. Have included MVFR fog at HIB and HYR for a brief window before sunrise, as surface winds will be lightest.

any fog will lift shortly after sunrise tomorrow. Winds become a bit blustery by late morning from the west, with gusts to 20kts through the afternoon.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/
Issued at 442 PM CDT Mon Aug 31 2026

Update...

Dense fog was slow to clear along the North Shore to near the Twin Ports. Therefore we extended the Dense Fog Advisory until 7 PM for the Two Harbors to Duluth to Port Wing zones. Expect fog to clear from southwest to northeast as winds over western Lake Superior turn westerly or southwesterly behind a cold front.
The front was already east of those areas over the land while the wind shift had not occurred over the waters as of 430 PM.

Previous discussion issued 1253 PM CDT Mon Aug 31 2026...

Areas of fog with patchy dense fog are ongoing right now. The coverage of dense fog is unknown, but from webcams, it does not appear to be widespread at this time, though the Duluth harbor cams do appear to have the lowest visibility. We will closely monitor conditions this afternoon for the need for some Marine Dense Fog Advisories. With drier air moving in, it is likely that fog will mix out around the head of the lake, though it may persist a bit longer further up the North Shore through this afternoon and possibly evening with west/southwest winds.
Outside of fog, expect light winds tonight, then increasing from the southwest on Tuesday. Gusts in the 20-25 kt range are likely along the North Shore and possibly also from Port Wing into the Apostle Islands. Wave heights to around 4 ft are expected from Grand Marais to Grand Portage with lower waves elsewhere. Winds are expected to decrease pretty quickly around sunset Tuesday evening. Small Craft Advisories will likely be needed Tuesday.

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

FIRE WEATHER
Issued at 1253 PM CDT Mon Aug 31 2026

Dry conditions are expected for much of northeast Minnesota this afternoon, excluding the Arrowhead, as skies clear out and occasionally blustery winds persist. RH may dip a bit below 40% for these areas this afternoon.

On Tuesday, a dry day is expected, especially in northwest Wisconsin. RH around 30% is likely there and there is a 30-60% chance that RH could dip into the 25-30% range. Winds will be a bit blustery with gusts to around 20 mph, and temperatures will be warm with highs in the 80s. Elevated fire weather conditions are possible. On the Minnesota side, similarly low RH may extend into Pine County and up into the Twin Ports and North Shore.
Gusty winds around 25 mph are expected in the Arrowhead, leading to potentially elevated fire weather conditions for some places there as well.

Lighter winds and a bit more moisture is expected Wednesday, so fire weather concerns are minimal. Thursday into the weekend, on-and-off rain chances should keep RH higher and therefore keep fire weather conditions minimal. Widespread wetting rains are not expected, but certainly some places will see some rainfall wherever storms develop.

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

DLH WATCHES/WARNINGS/ADVISORIES
MN...None.
WI...None.
MARINE...Dense Fog Advisory until 7 AM CDT Tuesday for LSZ140>142.
Dense Fog Advisory until 7 PM CDT this evening for LSZ143>145.