National Weather Service Marine Forecast FZUS63 KMQT

FZUS63 KMQT 240756
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
356 AM EDT Mon Aug 24 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 30.1 inch high pressure moves through the western Great Lakes today before moving into the Ohio River Valley by tonight. Meanwhile, 29.7 inch Clipper low pressure over Saskatchewan this morning moves over Lake Winnipeg on Tuesday. This Clipper moves over Lake Superior Tuesday night before lifting away towards James Bay and northern Quebec Wednesday night into Thursday morning. 30.0 inch high pressure ridging returns to Lake Superior by Thursday afternoon, increasing to 30.2 inches Thursday night into Friday as the high's center moves overhead.

LSZ162-242000
Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM
356 AM EDT Mon Aug 24 2026 /256 AM CDT Mon Aug 24 2026/

EARLY THIS MORNING
North winds less than 10 knots. Waves calm to 2 feet.

TODAY
North winds less than 10 knots becoming south 5 to 15 knots in the afternoon. Waves calm to 2 feet.

TONIGHT
East winds 5 to 15 knots becoming northeast less than 10 knots after midnight, then veering east late. Patchy fog after midnight. A slight chance of showers after midnight. Waves calm to 2 feet.

TUESDAY
East winds 5 to 15 knots veering south in the afternoon, then backing east late. A chance of showers and thunderstorms. Waves calm to 2 feet.

TUESDAY NIGHT
North winds 5 to 15 knots backing west after midnight. A chance of thunderstorms through midnight. A chance of showers. Waves calm to 2 feet.

WEDNESDAY
West winds 10 to 20 knots increasing to 15 to 25 knots by mid afternoon. A chance of showers. Waves calm to 2 feet.

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

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

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

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LSZ263-242000
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
356 AM EDT Mon Aug 24 2026

EARLY THIS MORNING
Northwest winds 5 to 15 knots. Waves calm to 2 feet.

TODAY
North winds 5 to 15 knots backing southwest late. Waves calm to 2 feet.

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

TUESDAY
South winds 5 to 15 knots backing southeast late. A chance of showers. A chance of thunderstorms by mid afternoon. Waves calm to 2 feet.

TUESDAY NIGHT
South winds 10 to 20 knots veering southwest after midnight. Showers through midnight. A chance of thunderstorms. A chance of showers after midnight. Waves calm to 2 feet.

WEDNESDAY
West winds 15 to 25 knots. A chance of showers. Waves building to 1 to 3 feet.

WEDNESDAY NIGHT
Northwest winds 10 to 20 knots diminishing to 5 to 15 knots after midnight. Waves subsiding to calm to 2 feet.

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

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

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LSZ264-242000
Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border
356 AM EDT Mon Aug 24 2026

EARLY THIS MORNING
Northwest winds 5 to 15 knots. Waves calm to 2 feet.

TODAY
North winds 5 to 15 knots backing west late. Waves calm to 2 feet.

TONIGHT
West winds 5 to 15 knots diminishing to less than 10 knots after midnight, then becoming south 5 to 15 knots late. Waves calm to 2 feet.

TUESDAY
South winds 5 to 15 knots backing southeast in the afternoon. A chance of showers. A slight chance of thunderstorms by mid afternoon. Waves calm to 2 feet.

TUESDAY NIGHT
South winds 10 to 20 knots veering southwest after midnight. Showers and a chance of thunderstorms. Waves building to 1 to 3 feet.

WEDNESDAY
West winds 10 to 20 knots. A chance of showers. Waves subsiding to calm to 2 feet, then building to 1 to 3 feet.

WEDNESDAY NIGHT
West winds 5 to 15 knots becoming northwest 10 to 20 knots after midnight. Waves subsiding to calm to 2 feet.

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

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

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LSZ265-242000
Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore
356 AM EDT Mon Aug 24 2026

EARLY THIS MORNING
Northwest winds 15 to 25 knots. Waves 2 to 4 feet.

TODAY
Northwest winds 15 to 25 knots diminishing to 5 to 15 knots late. Waves subsiding to calm to 2 feet.

TONIGHT
West winds 5 to 15 knots backing south late. Waves calm to 2 feet.

TUESDAY
South winds 5 to 15 knots becoming southeast 10 to 20 knots in the afternoon, then increasing to 15 to 25 knots late. A chance of showers and a slight chance of thunderstorms by mid afternoon. Waves calm to 2 feet.

TUESDAY NIGHT
South winds 15 to 25 knots veering southwest after midnight. Showers and a chance of thunderstorms. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet.

WEDNESDAY
West winds 15 to 25 knots. A chance of showers. Waves building to 1 to 3 feet.

WEDNESDAY NIGHT
West winds 15 to 25 knots veering northwest after midnight. Waves building to 2 to 4 feet.

THURSDAY
Northwest winds 15 to 25 knots diminishing to 10 to 20 knots. Waves subsiding to calm to 2 feet.

FRIDAY
North winds 10 to 20 knots becoming south 5 to 15 knots. Waves calm to 2 feet.

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LSZ266-242000
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
356 AM EDT Mon Aug 24 2026

EARLY THIS MORNING
North winds 15 to 25 knots. Waves 4 to 7 feet occasionally to 9 feet.

TODAY
North winds 15 to 25 knots backing northwest in the afternoon, then diminishing to 10 to 20 knots late. Waves subsiding to 1 to 3 feet.

TONIGHT
Northwest winds 5 to 15 knots backing southwest late. Waves subsiding to calm to 2 feet.

TUESDAY
South winds 5 to 15 knots becoming southeast 15 to 25 knots late. A slight chance of showers and thunderstorms by mid afternoon. Waves building to 1 to 3 feet.

TUESDAY NIGHT
South winds 15 to 25 knots. Showers and a chance of thunderstorms. Waves building to 2 to 4 feet.

WEDNESDAY
Southwest winds 10 to 20 knots veering west by mid afternoon. Showers likely through early afternoon. Waves subsiding to 1 to 3 feet.

WEDNESDAY NIGHT
West winds 15 to 25 knots veering northwest after midnight. Waves building to 2 to 4 feet.

THURSDAY
Northwest winds 15 to 25 knots diminishing to 5 to 15 knots. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to calm to 2 feet.

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

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LSZ267-242000
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border
356 AM EDT Mon Aug 24 2026

EARLY THIS MORNING
Northwest winds 20 to 30 knots. Waves 5 to 8 feet occasionally to 10 feet.

TODAY
Northwest winds 20 to 30 knots diminishing to 15 to 25 knots late. Waves subsiding to 2 to 4 feet.

TONIGHT
Northwest winds 10 to 20 knots diminishing to 5 to 15 knots after midnight, then backing west late. Waves subsiding to calm to 2 feet.

TUESDAY
South winds 5 to 15 knots backing southeast in the afternoon, then increasing to 10 to 20 knots late. Waves calm to 2 feet.

TUESDAY NIGHT
South winds 10 to 20 knots increasing to 15 to 25 knots after midnight. Showers and a chance of thunderstorms. Waves building to 2 to 4 feet.

WEDNESDAY
South winds 15 to 25 knots becoming west 10 to 20 knots by mid afternoon. Showers. Waves subsiding to calm to 2 feet.

WEDNESDAY NIGHT
West winds 10 to 20 knots becoming northwest 15 to 25 knots after midnight. Waves building to 2 to 4 feet.

THURSDAY
Northwest winds 15 to 25 knots diminishing to 10 to 20 knots. Waves subsiding to calm to 2 feet.

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

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LSZ261-241400
MAFOR 2409/ Superior West 12800 11100 12400 13300. Waves 1 foot or less.

Superior North Central 11710 11810 11710 11610 13600 11500. Waves 2 feet or less.

Superior South Central 13730 11720 11710 11610 11600 11500. Waves 2 to 4 feet subsiding to 1 to 3 feet today. Waves 2 feet or less tonight.

Superior East 11740 12730 12720 11710 12700. Waves 3 to 6 feet today. Waves 2 to 4 feet subsiding to 1 to 3 feet tonight.

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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