717
FZUS63 KMQT 240201
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1001 PM EDT Tue Sep 23 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...

High pressure over Lake Superior will build to 30.1 inches tonight
and persist through Wednesday. 29.8 inch troughing will move over
the lake on Thursday as a 29.3 inch low crosses Hudson Bay. 30.0
inch ridging briefly returns on Friday before another 29.3 inch low
crossing northern Ontario into Hudson Bay sends 29.7 inch troughing
back over the lake Friday night into Saturday.


LSZ162-240800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 PM EDT Tue Sep 23 2025 /901 PM CDT Tue Sep 23 2025/

.REST OF TONIGHT...North winds 5 to 15 knots backing northwest
late. Patchy dense fog. Waves calm to 2 feet.
.WEDNESDAY...North winds 5 to 15 knots veering south in the
afternoon. Patchy dense fog through early afternoon. Waves calm
to 2 feet.
.WEDNESDAY NIGHT...Southwest winds 5 to 15 knots. Waves calm to
2 feet.
.THURSDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Northwest winds 10 to 20 knots veering
northeast after midnight. Waves calm to 2 feet.
.FRIDAY...Northeast winds 10 to 20 knots veering east by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...East winds 5 to 15 knots veering west after
midnight. Waves calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots. Waves calm to 2 feet.
.SUNDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots. Waves calm to 2 feet.

$$

LSZ263-240800-
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 Tue Sep 23 2025

.REST OF TONIGHT...North winds less than 10 knots. Patchy dense
fog after midnight. Waves calm to 2 feet.
.WEDNESDAY...Northeast winds less than 10 knots increasing to
5 to 15 knots in the afternoon, then becoming north less than
10 knots late. Patchy fog through early afternoon. Waves calm to
2 feet.
.WEDNESDAY NIGHT...Southwest winds less than 10 knots increasing
to 5 to 15 knots late. Waves calm to 2 feet.
.THURSDAY...Southwest winds 10 to 20 knots. Waves building to
1 to 3 feet, then subsiding to calm to 2 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots veering northeast
after midnight. Waves building to 1 to 3 feet.
.FRIDAY...Northeast winds 10 to 20 knots becoming east 5 to
15 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 5 to 15 knots becoming southwest
10 to 20 knots after midnight. Waves calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots diminishing to 5 to
15 knots. Waves building to 1 to 3 feet, then subsiding to calm
to 2 feet.
.SUNDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.

$$

LSZ264-240800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 PM EDT Tue Sep 23 2025

.REST OF TONIGHT...North winds 5 to 15 knots veering northeast
late. Patchy fog after midnight. Waves calm to 2 feet.
.WEDNESDAY...Northeast winds 5 to 15 knots becoming north less
than 10 knots late. Patchy fog through early afternoon. Waves
calm to 2 feet.
.WEDNESDAY NIGHT...West winds less than 10 knots becoming
southwest 5 to 15 knots late. Waves calm to 2 feet.
.THURSDAY...Southwest winds 10 to 20 knots. Waves calm to 2 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots veering northeast
after midnight. Waves building to 1 to 3 feet.
.FRIDAY...Northeast winds 10 to 20 knots becoming east 5 to
15 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots increasing to 10 to
20 knots after midnight. Waves calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots. Waves building to 1 to
3 feet.
.SUNDAY...Southwest winds 5 to 15 knots. Waves subsiding to calm
to 2 feet.

$$

LSZ265-240800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 PM EDT Tue Sep 23 2025

.REST OF TONIGHT...North winds 10 to 20 knots. Patchy fog. Waves
calm to 2 feet.
.WEDNESDAY...North winds 10 to 20 knots diminishing to 5 to
15 knots late. Patchy fog through early afternoon. Waves calm to
2 feet.
.WEDNESDAY NIGHT...North winds 5 to 15 knots backing west late.
Waves calm to 2 feet.
.THURSDAY...West winds 5 to 15 knots backing southwest by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southwest winds 5 to 15 knots becoming north
10 to 20 knots after midnight. Waves calm to 2 feet.
.FRIDAY...North winds 10 to 20 knots becoming northeast 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 5 to 15 knots becoming south
10 to 20 knots after midnight. Waves calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots. Waves calm to 2 feet.
.SUNDAY...West winds 10 to 20 knots backing southwest. Waves calm
to 2 feet.

$$

LSZ266-240800-
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 Tue Sep 23 2025

.REST OF TONIGHT...North winds 10 to 20 knots veering northeast
after midnight. Patchy fog by midnight. Waves 1 to 3 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots backing north in the
afternoon, then diminishing to 5 to 15 knots late. Waves
subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...North winds 5 to 15 knots backing northwest
after midnight. Waves calm to 2 feet.
.THURSDAY...West winds 5 to 15 knots backing southwest by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southwest winds 5 to 15 knots becoming
northeast 10 to 20 knots after midnight. Waves calm to 2 feet.
.FRIDAY...Northeast winds 10 to 20 knots becoming north 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots increasing to 10 to
20 knots after midnight. Waves calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots. Waves building to 1 to
3 feet.
.SUNDAY...Southwest winds 10 to 20 knots. Waves subsiding to calm
to 2 feet.

$$

LSZ267-240800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 PM EDT Tue Sep 23 2025

.REST OF TONIGHT...North winds 10 to 20 knots veering northeast
late. Waves 1 to 3 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots becoming north 5 to
15 knots in the afternoon, then increasing to 10 to 20 knots
late. Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...North winds 5 to 15 knots backing northwest
late. Waves calm to 2 feet.
.THURSDAY...Northwest winds 5 to 15 knots backing west by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southwest winds 5 to 15 knots becoming east
10 to 20 knots after midnight. Waves calm to 2 feet.
.FRIDAY...Northeast winds 10 to 20 knots backing north by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots increasing to 10 to
20 knots after midnight. Waves calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.
.SUNDAY...West winds 10 to 20 knots backing southwest. Waves calm
to 2 feet.

$$

LSZ261-240800-
MAFOR 2403/
Superior West 11800 11700 19704 12800 19804 11800 11100 12400.
Waves 1 foot or less.

Superior North Central 11110 14100 11800 11700 11600. Waves 2
feet or less.

Superior South Central 15810 12800. Waves 1 to 2 feet.

Superior East 12120 13110 11810 12800. Waves 1 to 3 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