424
FZUS63 KMQT 010201
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1001 PM EDT Sun Aug 31 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...

30.2 inch high pressure remains sprawled out over the Great Lakes
through Monday. A 29.8 inch low looks to move near or over Lake
Superior late Tuesday/Tuesday night; expect the low to progressively
deepen to around 29.5 inches Wednesday. On Wednesday and Thursday,
this low lifts north toward James Bay then retrogrades northwestward
over northern Ontario before lifting into Hudson Bay late Friday.


LSZ162-010800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 PM EDT Sun Aug 31 2025 /901 PM CDT Sun Aug 31 2025/

.REST OF TONIGHT...South winds 5 to 15 knots veering southwest
after midnight. Isolated showers and thunderstorms after
midnight. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots. Isolated showers and
thunderstorms through early afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...Southwest winds 5 to 15 knots. Waves calm to
2 feet.
.TUESDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. A chance of showers and thunderstorms
by mid afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...Southwest winds 10 to 20 knots becoming
northwest 15 to 25 knots after midnight. Showers and a chance of
thunderstorms. Waves building to 1 to 3 feet.
.WEDNESDAY...North winds 15 to 25 knots increasing to 20 to
30 knots by mid afternoon. A chance of showers. Waves building to
2 to 4 feet.
.WEDNESDAY NIGHT...North winds 15 to 25 knots backing northwest
after midnight. A chance of showers. Waves 2 to 4 feet.
.THURSDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots. A chance of showers. Waves subsiding to calm to 2 feet.
.FRIDAY...Northwest winds 15 to 25 knots diminishing to 10 to
20 knots. Waves building to 1 to 3 feet.

$$

LSZ263-010800-
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 Sun Aug 31 2025

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

$$

LSZ264-010800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 PM EDT Sun Aug 31 2025

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

$$

LSZ265-010800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 PM EDT Sun Aug 31 2025

.REST OF TONIGHT...Southeast winds 5 to 15 knots veering
southwest late. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south late.
Isolated showers and thunderstorms by mid afternoon. Waves calm
to 2 feet.
.MONDAY NIGHT...South winds 5 to 15 knots veering southwest after
midnight. Waves calm to 2 feet.
.TUESDAY...Southwest winds 5 to 15 knots becoming southeast 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...South winds 10 to 20 knots veering southwest
after midnight. A slight chance of showers through midnight. A
chance of thunderstorms. Showers likely after midnight. Waves
calm to 2 feet.
.WEDNESDAY...West winds 15 to 25 knots becoming northwest 20 to
30 knots by mid afternoon. Showers through early afternoon. A
chance of thunderstorms. A chance of showers by mid afternoon.
Waves building to 2 to 4 feet.
.WEDNESDAY NIGHT...Northwest winds 15 to 25 knots. A chance of
showers. Waves subsiding to 1 to 3 feet.
.THURSDAY...West winds 15 to 25 knots. A chance of showers. Waves
subsiding to calm to 2 feet.
.FRIDAY...West winds 15 to 25 knots veering northwest. A chance
of showers. Waves calm to 2 feet.

$$

LSZ266-010800-
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 Sun Aug 31 2025

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

$$

LSZ267-010800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 PM EDT Sun Aug 31 2025

.REST OF TONIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.MONDAY...South winds 10 to 20 knots diminishing to 5 to 15 knots
in the afternoon, then backing southeast late. Waves calm to
2 feet.
.MONDAY NIGHT...South winds 5 to 15 knots increasing to 10 to
20 knots after midnight. Waves calm to 2 feet.
.TUESDAY...South winds 10 to 20 knots becoming southeast 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...South winds 10 to 20 knots. A slight chance of
showers and thunderstorms after midnight. Waves building to 1 to
3 feet.
.WEDNESDAY...South winds 15 to 25 knots veering west by mid
afternoon. Showers and a chance of thunderstorms. Waves building
to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots. Showers likely
through midnight, then a chance of showers after midnight. Waves
building to 3 to 6 feet occasionally to 8 feet.
.THURSDAY...West winds 15 to 25 knots becoming southwest 10 to
20 knots. A chance of showers. Waves subsiding to 2 to 4 feet.
.FRIDAY...West winds 15 to 25 knots veering northwest. A chance
of showers. Waves building to 3 to 5 feet occasionally to 7 feet.

$$

LSZ261-010800-
MAFOR 0103/
Superior West 11400 15500 11400. Waves 1 foot or less.

Superior North Central 12400 13500 11510 12500. Waves 1 to 2
feet.

Superior South Central 11300 11400 12500 11400 12300 11400. Waves
1 foot or less.

Superior East 11300 14400 11400 11300 11400. Waves 2 feet or
less.

$$

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