National Weather Service Marine Forecast FZUS63 KMQT

FZUS63 KMQT 092002
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
402 PM EDT Sun Aug 9 2026

For waters beyond 5 nautical miles of shore on Lake Superior.

Waves are the significant wave height - the average of the highest 1/3 of the wave spectrum. Occasional wave height is the average of the highest 1/10 of the wave spectrum.

SYNOPSIS

A 29.9 inch trough moves over the lake through tonight. Then, weak ridging of 29.9 inches returns on Monday and holds through Tuesday. Another weak trough at 29.8 inches moves over the lake Tuesday night into Wednesday before high pressure gradually builds over the Great Lakes from western Canada through Friday to 30.1 inches.

LSZ162-100800
Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM
402 PM EDT Sun Aug 9 2026 /302 PM CDT Sun Aug 9 2026/

LATE THIS AFTERNOON
East winds 5 to 15 knots. Waves calm to 2 feet.

TONIGHT
South winds 5 to 15 knots veering west after midnight. Patchy fog. Waves calm to 2 feet.

MONDAY
West winds 5 to 15 knots backing southwest in the afternoon, then becoming south 10 to 20 knots late. Waves calm to 2 feet.

MONDAY NIGHT
South winds 5 to 15 knots backing north after midnight. A slight chance of thunderstorms through midnight. A slight chance of showers. Waves calm to 2 feet.

TUESDAY
North winds 5 to 15 knots veering south by mid afternoon. A slight chance of showers through early afternoon. Waves calm to 2 feet.

TUESDAY NIGHT
Northwest winds 5 to 15 knots. A chance of showers. Waves calm to 2 feet.

WEDNESDAY
West winds 5 to 15 knots. Waves calm to 2 feet.

WEDNESDAY NIGHT
North winds 5 to 15 knots backing northwest after midnight. Waves calm to 2 feet.

THURSDAY
North winds 5 to 15 knots. Waves calm to 2 feet.

FRIDAY
East winds 5 to 15 knots backing northeast. Waves calm to 2 feet.

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LSZ263-100800
Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park
402 PM EDT Sun Aug 9 2026

LATE THIS AFTERNOON
East winds 5 to 15 knots. Waves calm to 2 feet.

TONIGHT
East winds 5 to 15 knots becoming west less than 10 knots after midnight, then increasing to 5 to 15 knots late. Patchy fog. Waves calm to 2 feet.

MONDAY
West winds 5 to 15 knots backing southwest in the afternoon, then increasing to 10 to 20 knots late. Patchy fog through early afternoon. Waves calm to 2 feet.

MONDAY NIGHT
Southwest winds 5 to 15 knots veering west after midnight, then diminishing to less than 10 knots late. A slight chance of showers after midnight. Waves calm to 2 feet.

TUESDAY
North winds less than 10 knots becoming south 5 to 15 knots by mid afternoon. A slight chance of showers through early afternoon. Waves calm to 2 feet.

TUESDAY NIGHT
Southwest winds 5 to 15 knots becoming west less than 10 knots after midnight. A chance of showers. Waves calm to 2 feet.

WEDNESDAY
West winds less than 10 knots increasing to 5 to 15 knots by mid afternoon. Waves calm to 2 feet.

WEDNESDAY NIGHT
Northwest winds 5 to 15 knots. Waves calm to 2 feet.

THURSDAY
Southwest winds 5 to 15 knots veering west. Waves calm to 2 feet.

FRIDAY
North winds 5 to 15 knots veering south. Waves calm to 2 feet.

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LSZ264-100800
Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border
402 PM EDT Sun Aug 9 2026

LATE THIS AFTERNOON
South winds 5 to 15 knots. Waves calm to 2 feet.

TONIGHT
South winds less than 10 knots veering west late. Patchy fog through midnight, then areas of dense fog after midnight. Waves calm to 2 feet.

MONDAY
West winds 5 to 15 knots backing southwest in the afternoon. Patchy fog. Waves calm to 2 feet.

MONDAY NIGHT
Southwest winds 5 to 15 knots veering west late. Waves calm to 2 feet.

TUESDAY
West winds less than 10 knots backing south by mid afternoon. A slight chance of showers through early afternoon. Waves calm to 2 feet.

TUESDAY NIGHT
Southwest winds less than 10 knots veering west after midnight. Waves calm to 2 feet.

WEDNESDAY
West winds less than 10 knots. Waves calm to 2 feet.

WEDNESDAY NIGHT
Northwest winds less than 10 knots increasing to 5 to 15 knots after midnight. Waves calm to 2 feet.

THURSDAY
West winds 5 to 15 knots. Waves calm to 2 feet.

FRIDAY
Northwest winds less than 10 knots backing south. Waves calm to 2 feet.

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LSZ265-100800
Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore
402 PM EDT Sun Aug 9 2026

LATE THIS AFTERNOON
East winds 10 to 20 knots. A slight chance of showers. Waves calm to 2 feet.

TONIGHT
East winds 5 to 15 knots backing north after midnight, then backing west late. A slight chance of showers through midnight. Patchy fog after midnight. Waves calm to 2 feet.

MONDAY
West winds 5 to 15 knots backing east late. Waves calm to 2 feet.

MONDAY NIGHT
South winds 5 to 15 knots becoming southwest 10 to 20 knots after midnight. Waves calm to 2 feet.

TUESDAY
Southwest winds 5 to 15 knots backing east by mid afternoon. A slight chance of showers. Waves calm to 2 feet.

TUESDAY NIGHT
Southeast winds 5 to 15 knots veering west after midnight. Waves calm to 2 feet.

WEDNESDAY
West winds 10 to 20 knots veering northwest by mid afternoon. Waves calm to 2 feet.

WEDNESDAY NIGHT
Northwest winds 10 to 20 knots. Waves calm to 2 feet.

THURSDAY
Northwest winds 5 to 15 knots backing west. Waves calm to 2 feet.

FRIDAY
Northeast winds 5 to 15 knots veering south. Waves calm to 2 feet.

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LSZ266-100800
Lake Superior East of a line from Manitou Island to Marquette MI and West of a line from Grand Marais MI to the US/Canadian Border Beyond 5NM from shore
402 PM EDT Sun Aug 9 2026

LATE THIS AFTERNOON
East winds 5 to 15 knots. A slight chance of showers. Waves calm to 2 feet.

TONIGHT
East winds 5 to 15 knots backing north after midnight. A slight chance of showers through midnight. Patchy fog. Waves calm to 2 feet.

MONDAY
West winds 5 to 15 knots. Patchy fog through early afternoon. Waves calm to 2 feet.

MONDAY NIGHT
Southwest winds 5 to 15 knots backing south after midnight. Waves calm to 2 feet.

TUESDAY
South winds 5 to 15 knots. A slight chance of showers. Waves calm to 2 feet.

TUESDAY NIGHT
South winds 5 to 15 knots veering west after midnight. Waves calm to 2 feet.

WEDNESDAY
West winds 5 to 15 knots veering northwest by mid afternoon. Waves calm to 2 feet.

WEDNESDAY NIGHT
Northwest winds 10 to 20 knots. Waves calm to 2 feet.

THURSDAY
Northwest winds 5 to 15 knots. Waves calm to 2 feet.

FRIDAY
Northwest winds 5 to 15 knots backing south. Waves calm to 2 feet.

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LSZ267-100800
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border
402 PM EDT Sun Aug 9 2026

LATE THIS AFTERNOON
East winds 10 to 20 knots. Waves calm to 2 feet.

TONIGHT
Northeast winds 5 to 15 knots backing north late. A slight chance of showers through midnight. Patchy fog. Waves calm to 2 feet.

MONDAY
Northwest winds 5 to 15 knots backing west in the afternoon, then veering northwest late. Patchy fog through early afternoon. Waves calm to 2 feet.

MONDAY NIGHT
West winds 5 to 15 knots backing south after midnight. Waves calm to 2 feet.

TUESDAY
South winds 5 to 15 knots backing east by mid afternoon. A slight chance of showers through early afternoon. Waves calm to 2 feet.

TUESDAY NIGHT
Northwest winds 5 to 15 knots. Waves calm to 2 feet.

WEDNESDAY
Northwest winds 5 to 15 knots. Waves calm to 2 feet.

WEDNESDAY NIGHT
Northwest winds 10 to 20 knots. Waves calm to 2 feet.

THURSDAY
Northwest winds 10 to 20 knots diminishing to 5 to 15 knots. Waves calm to 2 feet.

FRIDAY
Northwest winds 5 to 15 knots. Waves calm to 2 feet.

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LSZ261-100200
MAFOR 0921/ Superior West 12300 11500 14600 11510. Waves 1 foot or less.

Superior North Central 13400 12504 11500 11600 11510. Waves 1 foot or less.

Superior South Central 11210 12200 11800 11700 12610 11810. Waves 2 feet or less.

Superior East 11210 11110 11100 12804 11700 12600. Waves 2 feet or less.

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WFO MQT

Experimental modernized open lake forecast is available online at weather.gov/mqt/glftable

Graphical marine forecasts are available online at: weather.gov/greatlakes