National Weather Service Marine Forecast FZUS63 KMQT

FZUS63 KMQT 040155
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
955 PM EDT Tue Oct 3 2023

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
Tonight, a surface high pressure of 30.1 inches is centered over the northern Appalachians with a 29.4 inch low over southern Manitoba deepening to 29.2 inches while lifting to Hudson Bay on Wednesday. An associated 29.7 inch trough will sweep east, crossing Lake Superior Wednesday morning through Wednesday evening. On Thursday, 29.6 inch low pressure will develop southeast across far southern Manitoba into adjacent Ontario. As this low tracks across far northern Lake Superior on Thursday night, an associated trough will sweep across Lake Superior. Over the weekend, a 30.3 inch ridge over the Central Plains will drift east over the Plains states while weakening to 30.1 inches. Meanwhile a low will strengthen to 29.4 inches over southeastern Ontario.

LSZ162-041000
Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM
955 PM EDT Tue Oct 3 2023 /855 PM CDT Tue Oct 3 2023/

REST OF TONIGHT
South winds 10 to 20 knots increasing to 15 to 25 knots after midnight. A chance of showers and a slight chance of thunderstorms. Waves 1 to 3 feet building to 2 to 4 feet.

WEDNESDAY
Southwest winds 20 to 30 knots veering west late. A slight chance of thunderstorms through early afternoon. A chance of showers. Waves building to 3 to 6 feet occasionally to 8 feet.

WEDNESDAY NIGHT
West winds 15 to 25 knots diminishing to 10 to 20 knots after midnight, then backing southwest late. Waves subsiding to 1 to 3 feet, then building to 2 to 4 feet.

THURSDAY
Southwest winds 15 to 25 knots increasing to 20 to 30 knots by mid afternoon with a few gale force gusts to 35 knots possible late. Showers likely. Waves building to 4 to 7 feet occasionally to 9 feet.

THURSDAY NIGHT
West winds 20 to 30 knots and a few gale force gusts to 35 knots possible before diminishing to 15 to 25 knots late. A chance of showers. Waves subsiding to 3 to 6 feet occasionally to 8 feet.

FRIDAY
Northwest winds 15 to 25 knots. Showers likely. Waves 3 to 6 feet occasionally to 8 feet.

FRIDAY NIGHT
North winds 15 to 25 knots diminishing to 10 to 20 knots after midnight. A chance of showers. Waves subsiding to 2 to 4 feet.

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

SUNDAY
North winds 5 to 15 knots increasing to 10 to 20 knots. Waves calm to 2 feet.

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LSZ263-041000
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
955 PM EDT Tue Oct 3 2023

REST OF TONIGHT
South winds 15 to 25 knots increasing to 20 to 30 knots late. A chance of showers. Waves 1 to 3 feet building to 3 to 5 feet occasionally to 7 feet.

WEDNESDAY
South winds 20 to 30 knots veering west late. A chance of showers. Waves building to 3 to 6 feet occasionally to 8 feet.

WEDNESDAY NIGHT
West winds 15 to 25 knots diminishing to 10 to 20 knots after midnight, then backing southwest late. Waves subsiding to 2 to 4 feet.

THURSDAY
Southwest winds 15 to 25 knots increasing to 20 to 30 knots by mid afternoon with a few gale force gusts to 35 knots possible late. A chance of showers through early afternoon, then showers likely by mid afternoon. Waves building to 4 to 7 feet occasionally to 9 feet.

THURSDAY NIGHT
West winds 20 to 30 knots with a few gale force gusts to 35 knots possible. A chance of showers. Waves building to 5 to 8 feet occasionally to 10 feet.

FRIDAY
Northwest winds 15 to 25 knots becoming north 20 to 30 knots by mid afternoon with a few gale force gusts to 35 knots possible. Rain showers likely. Waves subsiding to 3 to 6 feet occasionally to 8 feet.

FRIDAY NIGHT
North winds 20 to 30 knots diminishing to 15 to 25 knots after midnight. A chance of rain showers. Waves subsiding to 3 to 5 feet occasionally to 7 feet.

SATURDAY
North winds 10 to 20 knots diminishing to 5 to 15 knots. A chance of rain showers. Waves subsiding to calm to 2 feet.

SUNDAY
North winds 10 to 20 knots. Waves building to 2 to 4 feet.

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LSZ264-041000
Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border
955 PM EDT Tue Oct 3 2023

REST OF TONIGHT
South winds 15 to 25 knots increasing to 20 to 30 knots late. A slight chance of showers after midnight. Waves 2 to 4 feet building to 3 to 6 feet occasionally to 8 feet.

WEDNESDAY
South winds 20 to 30 knots veering southwest in the afternoon, then diminishing to 15 to 25 knots late. A chance of showers. Waves subsiding to 3 to 5 feet occasionally to 7 feet.

WEDNESDAY NIGHT
West winds 15 to 25 knots diminishing to 10 to 20 knots after midnight. A slight chance of showers through midnight. Waves building to 3 to 6 feet occasionally to 8 feet, then subsiding to 2 to 4 feet.

THURSDAY
Southwest winds 15 to 25 knots. A chance of showers through early afternoon, then showers likely by mid afternoon. Waves building to 4 to 7 feet occasionally to 9 feet.

THURSDAY NIGHT
West winds 15 to 25 knots. A chance of showers. Waves 4 to 7 feet occasionally to 9 feet.

FRIDAY
Northwest winds 20 to 30 knots veering north by mid afternoon. Rain showers likely. Waves subsiding to 3 to 6 feet occasionally to 8 feet, then building to 5 to 8 feet occasionally to 10 feet.

FRIDAY NIGHT
North winds 20 to 30 knots diminishing to 15 to 25 knots after midnight. A chance of rain showers. Waves building to 5 to 9 feet occasionally to 11 feet.

SATURDAY
North winds 15 to 25 knots diminishing to 10 to 20 knots. A chance of rain showers. Waves subsiding to 1 to 3 feet.

SUNDAY
North winds 10 to 20 knots increasing to 15 to 25 knots. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet.

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LSZ265-041000
Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore
955 PM EDT Tue Oct 3 2023

REST OF TONIGHT
South winds 10 to 20 knots increasing to 15 to 25 knots late. A slight chance of showers after midnight. Waves 1 to 3 feet building to 2 to 4 feet, then subsiding to 1 to 3 feet.

WEDNESDAY
South winds 15 to 25 knots diminishing to 10 to 20 knots in the afternoon, then veering southwest late. A chance of showers. A slight chance of thunderstorms by mid afternoon. Waves subsiding to 1 to 3 feet.

WEDNESDAY NIGHT
West winds 5 to 15 knots increasing to 10 to 20 knots after midnight, then diminishing to 5 to 15 knots late. A chance of showers and a slight chance of thunderstorms through midnight. Waves subsiding to calm to 2 feet, then building to 1 to 3 feet.

THURSDAY
Southwest winds 5 to 15 knots. A slight chance of showers through early afternoon, then showers likely by mid afternoon. Waves calm to 2 feet.

THURSDAY NIGHT
West winds 10 to 20 knots. A chance of showers. Waves building to 1 to 3 feet.

FRIDAY
West winds 10 to 20 knots becoming northwest 20 to 30 knots by mid afternoon. Showers. Waves building to 4 to 7 feet occasionally to 9 feet.

FRIDAY NIGHT
North winds 20 to 30 knots. Showers. Waves building to 6 to 10 feet occasionally to 13 feet.

SATURDAY
North winds 15 to 25 knots diminishing to 10 to 20 knots. Showers likely, then a chance of showers. Waves subsiding to 2 to 4 feet.

SUNDAY
North winds 15 to 25 knots. A chance of showers. Waves building to 3 to 5 feet occasionally to 7 feet.

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LSZ266-041000
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
955 PM EDT Tue Oct 3 2023

REST OF TONIGHT
South winds 15 to 25 knots increasing to 20 to 30 knots late. Waves 3 to 6 feet occasionally to 8 feet.

WEDNESDAY
South winds 20 to 30 knots diminishing to 15 to 25 knots late. A chance of showers through early afternoon. A slight chance of thunderstorms. Showers likely by mid afternoon. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 5 feet occasionally to 7 feet.

WEDNESDAY NIGHT
West winds 15 to 25 knots diminishing to 10 to 20 knots after midnight. A chance of showers and thunderstorms. Waves building to 3 to 6 feet occasionally to 8 feet.

THURSDAY
Southwest winds 10 to 20 knots backing south by mid afternoon. A slight chance of showers through early afternoon, then showers likely by mid afternoon. Waves subsiding to 2 to 4 feet, then building to 3 to 5 feet occasionally to 7 feet.

THURSDAY NIGHT
Southwest winds 15 to 25 knots veering west after midnight. A chance of showers. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet.

FRIDAY
West winds 15 to 25 knots becoming northwest 20 to 30 knots by mid afternoon. Showers. Waves building to 5 to 8 feet occasionally to 10 feet.

FRIDAY NIGHT
North winds 20 to 30 knots. Showers. Waves building to 8 to 11 feet occasionally to 14 feet.

SATURDAY
North winds 15 to 25 knots. Rain showers likely, then a chance of rain showers. Waves subsiding to 3 to 5 feet occasionally to 7 feet.

SUNDAY
North winds 15 to 25 knots increasing to 20 to 30 knots. A chance of showers. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet.

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LSZ267-041000
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border
955 PM EDT Tue Oct 3 2023

REST OF TONIGHT
South winds 10 to 20 knots. Waves 1 to 3 feet building to 2 to 4 feet.

WEDNESDAY
South winds 15 to 25 knots. A chance of showers and a slight chance of thunderstorms. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet.

WEDNESDAY NIGHT
South winds 15 to 25 knots becoming west 5 to 15 knots after midnight. Showers likely through midnight. A chance of thunderstorms. A chance of showers after midnight. Waves subsiding to 1 to 3 feet, then building to 2 to 4 feet.

THURSDAY
Southwest winds 5 to 15 knots backing south by mid afternoon. A chance of showers through early afternoon, then showers likely by mid afternoon. Waves subsiding to calm to 2 feet.

THURSDAY NIGHT
Southwest winds 5 to 15 knots becoming west 10 to 20 knots after midnight. Showers likely through midnight, then a chance of showers after midnight. Waves building to 3 to 5 feet occasionally to 7 feet.

FRIDAY
West winds 10 to 20 knots increasing to 15 to 25 knots by mid afternoon. Showers. Waves building to 4 to 7 feet occasionally to 9 feet.

FRIDAY NIGHT
North winds 20 to 30 knots. Showers. Waves building to 6 to 10 feet occasionally to 13 feet.

SATURDAY
North winds 15 to 25 knots. Rain showers likely. Waves subsiding to 3 to 5 feet occasionally to 7 feet.

SUNDAY
North winds 15 to 25 knots increasing to 20 to 30 knots. A chance of rain showers. Waves building to 3 to 6 feet occasionally to 8 feet.

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LSZ261-041000
MAFOR 0403/ Superior West 13430 13540 12630. A chance of showers overnight and Wednesday morning. Waves 2 to 4 feet overnight. Waves 3 to 6 feet Wednesday and Wednesday evening.

Superior North Central 11430 14440 11540 12530. A chance of showers Wednesday. Waves 2 to 4 feet building to 3 to 6 feet Wednesday and Wednesday evening.

Superior South Central 15430 11520 11610. A chance of showers Wednesday and Wednesday evening. Waves 2 to 4 feet overnight and Wednesday subsiding to 1 to 3 feet Wednesday evening.

Superior East 13430 12440 12436 11536. A chance of thunderstorms Wednesday evening. Waves 2 to 4 feet building to 3 to 6 feet Wednesday and Wednesday evening.

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GS

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

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