984
FZUS63 KMQT 140201
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1001 PM EDT Wed Aug 13 2025

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 over Ontario will continue to build
southeast to Lake Superior tonight into early Thursday. A transition
to weak troughing of 29.9 inches is expected Thursday night into
Friday as high pressure pushes east from Ontario into Quebec and a
low pressure moves from northern Manitoba and Ontario to the Hudson
Bay. Another high pressure digging across the Canadian Prairies into
northern Ontario on Saturday brings 30.1 inch ridging over Lake
Superior for the weekend.


LSZ162-140800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 PM EDT Wed Aug 13 2025 /901 PM CDT Wed Aug 13 2025/

.REST OF TONIGHT...East winds 10 to 20 knots. Waves calm to
2 feet.
.THURSDAY...East winds 10 to 20 knots. A slight chance of showers
by mid afternoon. Waves building to 1 to 3 feet.
.THURSDAY NIGHT...East winds 10 to 20 knots veering south after
midnight. A chance of showers and thunderstorms. Waves 1 to
3 feet.
.FRIDAY...Southwest winds 10 to 20 knots. A slight chance of
showers. A slight chance of thunderstorms by mid afternoon. Waves
subsiding to calm to 2 feet.
.FRIDAY NIGHT...Southwest winds 5 to 15 knots veering north after
midnight. A chance of showers and thunderstorms. Waves calm to
2 feet.
.SATURDAY...Northeast winds 10 to 20 knots veering east by mid
afternoon. A chance of showers through early afternoon. Waves
calm to 2 feet.
.SATURDAY NIGHT...Northeast winds 10 to 20 knots increasing to
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.SUNDAY...East winds 15 to 25 knots. A chance of showers. Waves
building to 3 to 6 feet occasionally to 8 feet, then subsiding to
2 to 4 feet.
.MONDAY...East winds 10 to 20 knots backing northeast. A chance
of showers. Waves subsiding to 1 to 3 feet.

$$

LSZ263-140800-
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-
1001 PM EDT Wed Aug 13 2025

.REST OF TONIGHT...East winds 5 to 15 knots. Waves calm to
2 feet.
.THURSDAY...Southeast winds 5 to 15 knots backing east in the
afternoon, then increasing to 10 to 20 knots late. Waves building
to 1 to 3 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. A slight chance of showers and thunderstorms
after midnight. Waves building to 2 to 4 feet.
.FRIDAY...Southwest winds 10 to 20 knots. A slight chance of
showers. A slight chance of thunderstorms by mid afternoon. Waves
subsiding to 1 to 3 feet.
.FRIDAY NIGHT...Southwest winds 5 to 15 knots veering west after
midnight. A chance of showers and thunderstorms. Waves subsiding
to calm to 2 feet.
.SATURDAY...North winds 5 to 15 knots veering northeast by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.SATURDAY NIGHT...Northeast winds 5 to 15 knots increasing to
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.SUNDAY...East winds 15 to 25 knots. Waves building to 3 to
6 feet occasionally to 8 feet, then subsiding to 1 to 3 feet.
.MONDAY...East winds 10 to 20 knots. Waves 1 to 3 feet.

$$

LSZ264-140800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 PM EDT Wed Aug 13 2025

.REST OF TONIGHT...North winds 5 to 15 knots veering east late.
Waves calm to 2 feet.
.THURSDAY...East winds 5 to 15 knots veering southeast in the
afternoon, then increasing to 10 to 20 knots late. Waves building
to 1 to 3 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. Waves building to 2 to 4 feet.
.FRIDAY...South winds 10 to 20 knots becoming southwest 5 to
15 knots by mid afternoon. A slight chance of showers. A slight
chance of thunderstorms by mid afternoon. Waves subsiding to 1 to
3 feet.
.FRIDAY NIGHT...Southwest winds 5 to 15 knots veering west after
midnight. A chance of showers and a slight chance of
thunderstorms. Waves subsiding to calm to 2 feet.
.SATURDAY...North winds 5 to 15 knots. A chance of showers. Waves
calm to 2 feet.
.SATURDAY NIGHT...North winds 5 to 15 knots becoming northeast
10 to 20 knots after midnight. Waves building to 1 to 3 feet.
.SUNDAY...East winds 15 to 25 knots diminishing to 10 to
20 knots. Waves building to 2 to 4 feet, then subsiding to calm
to 2 feet.
.MONDAY...East winds 10 to 20 knots. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.

$$

LSZ265-140800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 PM EDT Wed Aug 13 2025

.REST OF TONIGHT...North winds 10 to 20 knots becoming northeast
5 to 15 knots late. Waves calm to 2 feet.
.THURSDAY...East winds 5 to 15 knots increasing to 15 to
25 knots. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots becoming south
15 to 25 knots after midnight. Waves calm to 2 feet.
.FRIDAY...South winds 10 to 20 knots. Waves calm to 2 feet.
.FRIDAY NIGHT...Southwest winds 10 to 20 knots veering west after
midnight. A chance of showers and a slight chance of
thunderstorms. Waves calm to 2 feet.
.SATURDAY...North winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
.SATURDAY NIGHT...North winds 10 to 20 knots veering northeast
after midnight. Waves building to 1 to 3 feet.
.SUNDAY...Northeast winds 15 to 25 knots becoming east 10 to
20 knots. Waves subsiding to calm to 2 feet.
.MONDAY...East winds 10 to 20 knots. A chance of showers. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.

$$

LSZ266-140800-
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-
1001 PM EDT Wed Aug 13 2025

.REST OF TONIGHT...North winds 10 to 20 knots becoming northeast
5 to 15 knots late. Waves calm to 2 feet.
.THURSDAY...East winds 5 to 15 knots increasing to 10 to 20 knots
late. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots becoming south
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.FRIDAY...South winds 15 to 25 knots diminishing to 10 to
20 knots by mid afternoon. A slight chance of showers and
thunderstorms by mid afternoon. Waves subsiding to 1 to 3 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots veering southwest
after midnight. A chance of showers and a slight chance of
thunderstorms. Waves subsiding to calm to 2 feet.
.SATURDAY...Northwest winds 10 to 20 knots veering north by mid
afternoon. A chance of showers. Waves calm to 2 feet.
.SATURDAY NIGHT...North winds 10 to 20 knots veering northeast
after midnight. Waves building to 2 to 4 feet.
.SUNDAY...Northeast winds 10 to 20 knots veering east. Waves
subsiding to calm to 2 feet, then building to 1 to 3 feet.
.MONDAY...East winds 10 to 20 knots. Waves subsiding to calm to
2 feet.

$$

LSZ267-140800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 PM EDT Wed Aug 13 2025

.REST OF TONIGHT...Northwest winds 10 to 20 knots veering
northeast late. Waves calm to 2 feet.
.THURSDAY...East winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 5 to 15 knots becoming south
10 to 20 knots after midnight. Waves building to 1 to 3 feet.
.FRIDAY...South winds 10 to 20 knots. Waves 1 to 3 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots becoming southwest
10 to 20 knots after midnight. A chance of showers and
thunderstorms. Waves subsiding to calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots veering northwest by mid
afternoon. A chance of showers and thunderstorms. Waves calm to
2 feet.
.SATURDAY NIGHT...Northwest winds 10 to 20 knots becoming
northeast 15 to 25 knots after midnight. Waves building to 2 to
4 feet.
.SUNDAY...Northeast winds 10 to 20 knots veering east. Waves
subsiding to calm to 2 feet, then building to 1 to 3 feet.
.MONDAY...Southeast winds 10 to 20 knots backing east. A chance
of showers. Waves subsiding to calm to 2 feet.

$$

LSZ261-140800-
MAFOR 1403/
Superior West 12210 13310 11210 12220. Waves 2 feet or less
overnight and Thursday. Waves 2 to 3 feet Thursday evening.

Superior North Central 11810 11100 12200 11310 13320. Waves 1 to
3 feet.

Superior South Central 11810 12100 11200 11210 11220 11230 11320.
Waves 1 to 2 feet.

Superior East 11810 12110 12210 12200 11310. Waves 1 to 2 feet.

$$

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