711
FZUS63 KMQT 180201
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1001 PM EDT Fri Oct 17 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...

29.2 inch low pressure is moving towards Hudson Bay tonight, and
should be deepening to 29.1 inches into Saturday. As a result, a
29.5 inch trough is moving over Lake Superior tonight, and will be
followed by a second 29.5 inch trough Saturday. A secondary low
develops over the Mid Mississippi Valley at the base of this
secondary trough late in the day Saturday, then deepens to at least
29.3 inches on Sunday as it crosses Lower Michigan. This low reaches
James Bay Sunday night while a weak 29.7 inch ridge briefly extends
over Lake Superior. Another low pressure at 29.5 inches develops
upstream over the Northern Plains, tracking east over the region
Monday night before coalescing into a compact 29.4 inch low over the
Upper Great Lakes Tuesday morning.


LSZ162-180800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 PM EDT Fri Oct 17 2025 /901 PM CDT Fri Oct 17 2025/

.REST OF TONIGHT...Southwest winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves 2 to 4 feet subsiding to
1 to 3 feet.
.SATURDAY...Southwest winds 5 to 15 knots becoming west 10 to
20 knots in the afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...Northwest winds 10 to 20 knots increasing to
15 to 25 knots after midnight. A slight chance of showers. Waves
building to 1 to 3 feet.
.SUNDAY...Northwest winds 15 to 25 knots. Waves building to 2 to
4 feet, then subsiding to 1 to 3 feet.
.SUNDAY NIGHT...West winds 10 to 20 knots becoming southwest 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...South winds 10 to 20 knots increasing to 15 to 25 knots
by mid afternoon. A chance of showers through early afternoon,
then showers likely by mid afternoon. Waves building to 2 to
4 feet, then subsiding to 1 to 3 feet.
.MONDAY NIGHT...West winds 15 to 25 knots becoming northwest
20 to 30 knots after midnight. Showers likely. Waves building to
2 to 4 feet.
.TUESDAY...Northwest gales to 35 knots diminishing to 15 to
25 knots. A chance of rain showers. Waves building to 3 to 6 feet
occasionally to 8 feet, then subsiding to calm to 2 feet.
.WEDNESDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots. Waves calm to 2 feet.

$$

LSZ263-180800-
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 Fri Oct 17 2025

.REST OF TONIGHT...Southwest winds 15 to 25 knots diminishing to
10 to 20 knots late. Waves 2 to 4 feet building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 2 to 4 feet.
.SATURDAY...Southwest winds 5 to 15 knots veering west in the
afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...Northwest winds 5 to 15 knots increasing to
15 to 25 knots. A slight chance of showers. Waves building to
3 to 5 feet occasionally to 7 feet.
.SUNDAY...Northwest winds 20 to 30 knots. A slight chance of
showers through early afternoon. Waves building to 3 to 6 feet
occasionally to 8 feet.
.SUNDAY NIGHT...Northwest winds 15 to 25 knots becoming west 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...South winds 15 to 25 knots backing southeast by mid
afternoon. A chance of showers through early afternoon, then
showers likely by mid afternoon. Waves building to 2 to 4 feet,
then subsiding to 1 to 3 feet.
.MONDAY NIGHT...West winds 15 to 25 knots becoming northwest
gales to 35 knots after midnight. Showers likely. Waves building
to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...Northwest gales to 35 knots veering north. Rain
showers likely. Waves building to 6 to 9 feet occasionally to
11 feet, then subsiding to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...West winds 15 to 25 knots becoming southwest 10 to
20 knots. Waves subsiding to calm to 2 feet, then building to
1 to 3 feet.

$$

LSZ264-180800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 PM EDT Fri Oct 17 2025

.REST OF TONIGHT...Southwest winds 15 to 25 knots diminishing to
10 to 20 knots late. Scattered showers by midnight. Waves 3 to
5 feet occasionally to 7 feet subsiding to 2 to 4 feet.
.SATURDAY...West winds 5 to 15 knots. Waves subsiding to calm to
2 feet.
.SATURDAY NIGHT...West winds 5 to 15 knots becoming northwest
10 to 20 knots after midnight, then increasing to 15 to 25 knots
late. A chance of showers. Waves building to 2 to 4 feet.
.SUNDAY...Northwest winds 20 to 30 knots. A slight chance of
showers through early afternoon. Waves building to 4 to 7 feet
occasionally to 9 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.
.SUNDAY NIGHT...Northwest winds 15 to 25 knots becoming west 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...South winds 10 to 20 knots becoming southeast 15 to
25 knots by mid afternoon. A chance of showers. Waves building to
2 to 4 feet.
.MONDAY NIGHT...South winds 15 to 25 knots becoming northwest
gales to 35 knots after midnight. Showers likely. Waves building
to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...North gales to 35 knots. Rain showers likely, then a
chance of rain showers. Waves building to 6 to 9 feet
occasionally to 11 feet, then subsiding to 4 to 7 feet
occasionally to 9 feet.
.WEDNESDAY...Northwest winds 15 to 25 knots becoming west 10 to
20 knots. Waves subsiding to calm to 2 feet, then building to
1 to 3 feet.

$$

LSZ265-180800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 PM EDT Fri Oct 17 2025

.REST OF TONIGHT...Southwest winds 10 to 20 knots. Isolated
showers by midnight. Waves 2 to 4 feet subsiding to calm to
2 feet.
.SATURDAY...Southwest winds 10 to 20 knots becoming west 5 to
15 knots in the afternoon, then veering northeast late. Waves
calm to 2 feet.
.SATURDAY NIGHT...Northwest winds 5 to 15 knots becoming north
10 to 20 knots after midnight, then becoming northwest 15 to
25 knots late. A chance of showers. Waves building to 2 to
4 feet.
.SUNDAY...Northwest gales to 35 knots. A chance of showers. Waves
building to 4 to 7 feet occasionally to 9 feet.
.SUNDAY NIGHT...Northwest winds 20 to 30 knots becoming west
10 to 20 knots after midnight. A slight chance of showers through
midnight. Waves subsiding to calm to 2 feet.
.MONDAY...South winds 10 to 20 knots increasing to 20 to 30 knots
by mid afternoon. Showers likely by mid afternoon. Waves calm to
2 feet.
.MONDAY NIGHT...South winds 20 to 30 knots becoming west gales to
35 knots after midnight. Showers. Waves building to 2 to 4 feet.
.TUESDAY...Northwest gales to 35 knots veering north. Showers,
then a chance of showers. Waves building to 6 to 9 feet
occasionally to 11 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.
.WEDNESDAY...Northwest winds 15 to 25 knots becoming west 10 to
20 knots. A chance of showers. Waves subsiding to calm to 2 feet.

$$

LSZ266-180800-
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 Fri Oct 17 2025

...GALE WATCH IN EFFECT FROM SUNDAY MORNING THROUGH SUNDAY
EVENING...

.REST OF TONIGHT...South winds 15 to 25 knots veering southwest
after midnight, then diminishing to 10 to 20 knots late.
Scattered showers. Waves 4 to 7 feet occasionally to 9 feet
subsiding to 2 to 4 feet.
.SATURDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then backing northeast late. A slight
chance of showers by mid afternoon. Waves subsiding to calm to
2 feet.
.SATURDAY NIGHT...Northeast winds 5 to 15 knots becoming north
10 to 20 knots after midnight, then increasing to 15 to 25 knots
late. A chance of showers through midnight, then showers likely
after midnight. Waves building to 2 to 4 feet.
.SUNDAY...North gales to 35 knots backing northwest by mid
afternoon. A chance of showers. Waves building to 8 to 11 feet
occasionally to 14 feet.
.SUNDAY NIGHT...Northwest winds 20 to 30 knots diminishing to
10 to 20 knots after midnight. A chance of showers through
midnight. Waves subsiding to 3 to 5 feet occasionally to 7 feet.
.MONDAY...South winds 10 to 20 knots increasing to 15 to 25 knots
by mid afternoon. A chance of showers. Waves subsiding to 1 to
3 feet, then building to 2 to 4 feet.
.MONDAY NIGHT...South winds 15 to 25 knots becoming west gales to
35 knots after midnight. Showers. Waves building to 4 to 7 feet
occasionally to 9 feet.
.TUESDAY...Northwest gales to 35 knots veering north. Showers,
then a chance of showers. Waves building to 8 to 11 feet
occasionally to 14 feet, then subsiding to 5 to 8 feet
occasionally to 10 feet.
.WEDNESDAY...Northwest winds 15 to 25 knots becoming west 10 to
20 knots. A chance of showers. Waves subsiding to 1 to 3 feet.

$$

LSZ267-180800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 PM EDT Fri Oct 17 2025

...GALE WATCH IN EFFECT FROM SUNDAY MORNING THROUGH SUNDAY
EVENING...

.REST OF TONIGHT...South winds 20 to 30 knots diminishing to
15 to 25 knots after midnight, then becoming southwest 10 to
20 knots late. Numerous showers by midnight, then a chance of
showers after midnight. Waves 3 to 6 feet occasionally to 8 feet
subsiding to 1 to 3 feet.
.SATURDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then veering north late. A slight
chance of showers. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots backing northeast
after midnight, then becoming north 10 to 20 knots late. A chance
of showers through midnight, then showers likely after midnight.
Waves building to 1 to 3 feet.
.SUNDAY...North winds 20 to 30 knots becoming northwest gales to
35 knots by mid afternoon. Showers likely through early
afternoon, then a chance of showers by mid afternoon. Waves
building to 8 to 12 feet occasionally to 15 feet.
.SUNDAY NIGHT...Northwest winds 20 to 30 knots diminishing to
15 to 25 knots after midnight. A chance of showers through
midnight. Waves subsiding to 3 to 5 feet occasionally to 7 feet.
.MONDAY...Southwest winds 10 to 20 knots becoming south 15 to
25 knots by mid afternoon. A chance of showers. Waves subsiding
to 1 to 3 feet, then building to 2 to 4 feet.
.MONDAY NIGHT...Southeast winds 20 to 30 knots. Showers. Waves
building to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...Northwest gales to 35 knots veering north. Showers.
Waves building to 7 to 10 feet occasionally to 13 feet, then
subsiding to 5 to 8 feet occasionally to 10 feet.
.WEDNESDAY...Northwest winds 15 to 25 knots diminishing to 10 to
20 knots. A chance of showers. Waves subsiding to 1 to 3 feet.

$$

LSZ261-180800-
MAFOR 1803/
Superior West 11530 11520 12510 13610 11720. Waves 3 to 5 feet
subsiding to 2 to 4 feet overnight. Waves 1 to 3 feet Saturday
and Saturday evening.

Superior North Central 11530 19536 12520 13610 11600 11610. Waves
3 to 5 feet overnight. Waves 3 to 5 feet subsiding to 2 to 3 feet
Saturday. Waves 1 to 2 feet Saturday evening.

Superior South Central 11530 13510 11500 11700 11100 11800. A
chance of showers Saturday evening. Waves 2 to 4 feet subsiding
to 1 to 3 feet overnight. Waves 2 feet or less Saturday and
Saturday evening.

Superior East 11440 19446 11520 11510 12500 11600 11800 11100.
Waves 3 to 6 feet overnight. Waves 1 to 3 feet Saturday and
Saturday evening.

$$

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