474
FZUS63 KMQT 170201
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1001 PM EDT Thu Oct 16 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 centered over the Lower Great Lakes shifts
east tonight while a 29.6 inch low over North Dakota deepens to 29.5
inches, lifting toward Manitoba. This low deepens to 29.2 inches on
Friday as it crosses northeast over Lake Winnipeg, continuing
northeast to Hudson Bay through Saturday afternoon. As a result, a
29.6 inch trough is sent over Lake Superior Friday afternoon through
Saturday. A secondary low develops over the Mid Mississippi Valley
late in the day Saturday, deepening to at least 29.2 inches on
Sunday as it crosses Lower Michigan. This low reaches Quebec by
Monday morning while a weak 29.7 inch ridge briefly extends over
Lake Superior. Meanwhile, another low pressure at 29.5 inches is
developing upstream over the Northern Plains, tracking east over the
region Monday night through Tuesday.


LSZ162-170800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 PM EDT Thu Oct 16 2025 /901 PM CDT Thu Oct 16 2025/

.REST OF TONIGHT...Southeast winds 10 to 20 knots becoming south
5 to 15 knots after midnight, then becoming southeast 10 to
20 knots late. A chance of showers. Waves 1 to 3 feet subsiding
to calm to 2 feet.
.FRIDAY...South winds 10 to 20 knots becoming southwest 15 to
25 knots late. A chance of showers. Waves building to 1 to
3 feet.
.FRIDAY NIGHT...Southwest winds 20 to 30 knots diminishing to
10 to 20 knots. Waves building to 2 to 4 feet, then subsiding to
1 to 3 feet.
.SATURDAY...West winds 10 to 20 knots. 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 backing west by mid
afternoon. Waves subsiding to calm to 2 feet.
.SUNDAY NIGHT...West winds 10 to 20 knots backing southwest after
midnight. Waves calm to 2 feet.
.MONDAY...South winds 15 to 25 knots veering west. A chance of
showers. Waves building to 2 to 4 feet, then subsiding to 1 to
3 feet.
.TUESDAY...Northwest winds 20 to 30 knots diminishing to 15 to
25 knots. A chance of rain showers. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 1 to 3 feet.

$$

LSZ263-170800-
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 Thu Oct 16 2025

.REST OF TONIGHT...South winds 10 to 20 knots diminishing to 5 to
15 knots after midnight, then increasing to 10 to 20 knots late.
A chance of showers. Waves 1 to 3 feet.
.FRIDAY...South winds 10 to 20 knots veering southwest late. A
chance of showers. Waves 1 to 3 feet.
.FRIDAY NIGHT...Southwest winds 15 to 25 knots. A slight chance
of showers through midnight. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 2 to 4 feet.
.SATURDAY...West winds 10 to 20 knots. Waves subsiding to 1 to
3 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 3 to 5 feet occasionally to 7 feet.
.SUNDAY...Northwest winds 20 to 30 knots backing west by mid
afternoon. Waves building to 3 to 6 feet occasionally to 8 feet.
.SUNDAY NIGHT...West winds 10 to 20 knots backing southwest after
midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...South winds 15 to 25 knots veering west. A chance of
showers. Waves building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...Northwest winds 20 to 30 knots. A chance of rain
showers. Waves building to 4 to 7 feet occasionally to 9 feet,
then subsiding to 3 to 5 feet occasionally to 7 feet.

$$

LSZ264-170800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 PM EDT Thu Oct 16 2025

.REST OF TONIGHT...Southeast winds 15 to 25 knots veering south
after midnight, then diminishing to 10 to 20 knots late. A chance
of showers by midnight, then showers likely after midnight. Waves
3 to 6 feet occasionally to 8 feet.
.FRIDAY...South winds 10 to 20 knots. A chance of showers. Waves
subsiding to 3 to 5 feet occasionally to 7 feet.
.FRIDAY NIGHT...Southwest winds 15 to 25 knots diminishing to
10 to 20 knots late. A chance of showers through midnight. Waves
3 to 5 feet occasionally to 7 feet.
.SATURDAY...West winds 10 to 20 knots. Waves subsiding to 1 to
3 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 3 to 5 feet occasionally to 7 feet.
.SUNDAY...Northwest winds 20 to 30 knots. 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 1 to 3 feet.
.MONDAY...South winds 15 to 25 knots. A chance of showers. Waves
building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...Northwest winds 20 to 30 knots veering north. A chance
of rain showers. Waves building to 4 to 7 feet occasionally to
9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet.

$$

LSZ265-170800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 PM EDT Thu Oct 16 2025

.REST OF TONIGHT...South winds 15 to 25 knots diminishing to
10 to 20 knots after midnight, then increasing to 15 to 25 knots
late. A chance of showers and a slight chance of thunderstorms.
Waves 3 to 5 feet occasionally to 7 feet subsiding to 2 to
4 feet.
.FRIDAY...South winds 15 to 25 knots. A chance of showers. A
slight chance of thunderstorms by mid afternoon. Waves building
to 3 to 5 feet occasionally to 7 feet, then subsiding to 2 to
4 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots veering southwest
after midnight, then diminishing to 10 to 20 knots late. A slight
chance of thunderstorms through midnight. A chance of showers.
Waves subsiding to calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots veering northwest by mid
afternoon. A slight chance of showers by mid afternoon. Waves
calm to 2 feet.
.SATURDAY NIGHT...Northwest winds 10 to 20 knots increasing to
15 to 25 knots after midnight. A chance of showers. Waves
building to 1 to 3 feet.
.SUNDAY...Northwest winds 20 to 30 knots. A chance of showers.
Waves building to 3 to 5 feet occasionally to 7 feet.
.SUNDAY NIGHT...West winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...South winds 15 to 25 knots. A chance of showers. Waves
building to 1 to 3 feet.
.TUESDAY...Northwest winds 20 to 30 knots. Showers likely, then a
chance of showers. Waves building to 3 to 6 feet occasionally to
8 feet.

$$

LSZ266-170800-
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 Thu Oct 16 2025

.REST OF TONIGHT...South winds 15 to 25 knots increasing to 20 to
30 knots after midnight. Showers and a slight chance of
thunderstorms. Waves 3 to 5 feet occasionally to 7 feet building
to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to
6 feet occasionally to 8 feet.
.FRIDAY...South winds 20 to 30 knots. A chance of showers. A
slight chance of thunderstorms by mid afternoon. Waves building
to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to
6 feet occasionally to 8 feet.
.FRIDAY NIGHT...South winds 20 to 30 knots becoming southwest
15 to 25 knots after midnight, then diminishing to 10 to 20 knots
late. Showers through midnight. A slight chance of thunderstorms.
A chance of showers after midnight. Waves building to 4 to 7 feet
occasionally to 9 feet, then subsiding to 3 to 5 feet
occasionally to 7 feet.
.SATURDAY...Southwest winds 10 to 20 knots veering west by mid
afternoon. A slight chance of showers. Waves subsiding to 1 to
3 feet.
.SATURDAY NIGHT...Northwest winds 10 to 20 knots becoming north
15 to 25 knots after midnight. A chance of showers. A slight
chance of thunderstorms after midnight. Waves building to 2 to
4 feet.
.SUNDAY...Northwest winds 20 to 30 knots. A chance of showers.
Waves building to 5 to 8 feet occasionally to 10 feet.
.SUNDAY NIGHT...Northwest winds 15 to 25 knots backing west after
midnight. Waves subsiding to 2 to 4 feet.
.MONDAY...South winds 15 to 25 knots. A chance of showers. Waves
building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...Northwest winds 20 to 30 knots. Showers likely, then a
chance of showers. Waves building to 5 to 8 feet occasionally to
10 feet.

$$

LSZ267-170800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 PM EDT Thu Oct 16 2025

.REST OF TONIGHT...South winds 10 to 20 knots increasing to 15 to
25 knots after midnight. Showers. Waves calm to 2 feet building
to 3 to 5 feet occasionally to 7 feet.
.FRIDAY...South winds 15 to 25 knots increasing to 30 knots with
a few gale force gusts to 35 knots possible. A slight chance of
showers. Waves subsiding to 2 to 4 feet, then building to 3 to
6 feet occasionally to 8 feet.
.FRIDAY NIGHT...South winds 20 to 30 knots becoming southwest
15 to 25 knots late. Showers and a slight chance of
thunderstorms. Waves subsiding to 1 to 3 feet.
.SATURDAY...Southwest winds 10 to 20 knots. A slight chance of
thunderstorms through early afternoon. A chance of showers. Waves
subsiding to calm to 2 feet.
.SATURDAY NIGHT...Southeast winds 10 to 20 knots backing north
after midnight. Showers likely. A slight chance of thunderstorms
after midnight. Waves building to 1 to 3 feet.
.SUNDAY...North winds 15 to 25 knots becoming northwest 20 to
30 knots by mid afternoon. Showers likely through early
afternoon, then a chance of showers by mid afternoon. Waves
building to 5 to 9 feet occasionally to 11 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 2 to 4 feet.
.MONDAY...South winds 15 to 25 knots. A chance of showers, then
showers likely. Waves building to 3 to 5 feet occasionally to
7 feet.
.TUESDAY...Northwest winds 20 to 30 knots. Showers. Waves
building to 5 to 8 feet occasionally to 10 feet.

$$

LSZ261-170800-
MAFOR 1703/
Superior West 11416 12410 13420 11520 11530. Waves 1 to 3 feet
overnight and Friday. Waves 2 to 4 feet Friday evening.

Superior North Central 11430 12426 14420 11430. Waves 3 to 6
feet.

Superior South Central 11436 15430 11430. Waves 2 to 4 feet
building to 3 to 5 feet overnight. Waves 3 to 6 feet Friday and
Friday evening.

Superior East 14436 11430 12440 11446. Waves 2 to 4 feet building
to 3 to 5 feet overnight. Waves 3 to 6 feet Friday. Waves 4 to 7
feet Friday evening.

$$

WFO MQT

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