848
FZUS63 KMQT 120801
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 AM EDT Sun Oct 12 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...

30.0 inch ridging over Lake Superior weakens this morning as the
parent high moves into the St. Lawrence Seaway. The next system over
the Northern Plains at 29.2 inches lifts northeast from southern
Manitoba to Hudson Bay through Monday. This low extends a 29.8 inch
trough over western Lake Superior late in the day into Monday. A
30.5 inch high builds in over the Canadian Prairies Monday night
into Tuesday, shifting east to the Great Lakes and northern Ontario
by Wednesday at 30.3 inches. Ridging gradually weakens to 30.1
inches over Lake Superior through Thursday as troughing develops
over the Plains and the parent high shifts northeast.


LSZ162-122000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
401 AM EDT Sun Oct 12 2025 /301 AM CDT Sun Oct 12 2025/

.EARLY THIS MORNING...South winds 15 to 25 knots. Waves 3 to
5 feet occasionally to 7 feet.
.TODAY...South winds 15 to 25 knots backing southeast in the
afternoon. A slight chance of showers by mid afternoon. Waves
subsiding to 2 to 4 feet, then building to 3 to 5 feet
occasionally to 7 feet.
.TONIGHT...Southeast winds 15 to 25 knots becoming south 20 to
30 knots after midnight, then veering southwest late. Showers
likely through midnight, then a chance of showers after midnight.
Waves building to 4 to 7 feet occasionally to 9 feet, then
subsiding to 3 to 6 feet occasionally to 8 feet.
.MONDAY...West winds 20 to 30 knots diminishing to 15 to 25 knots
in the afternoon. Waves subsiding to 2 to 4 feet.
.MONDAY NIGHT...Northwest winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to calm to 2 feet.
.TUESDAY...Northwest winds 10 to 20 knots diminishing to 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...North winds 5 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...East winds 5 to 15 knots. Waves calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots increasing to 15 to
25 knots. A chance of showers, then showers likely. Waves
building to 3 to 5 feet occasionally to 7 feet.

$$

LSZ263-122000-
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-
401 AM EDT Sun Oct 12 2025

.EARLY THIS MORNING...South winds 15 to 25 knots. Waves 3 to
5 feet occasionally to 7 feet.
.TODAY...South winds 15 to 25 knots backing southeast late. Waves
building to 3 to 6 feet occasionally to 8 feet.
.TONIGHT...Southeast winds 20 to 30 knots veering south after
midnight. A chance of showers. Waves building to 4 to 7 feet
occasionally to 9 feet.
.MONDAY...West winds 20 to 30 knots. A slight chance of showers
through early afternoon. Waves subsiding to 3 to 6 feet
occasionally to 8 feet, then building to 4 to 7 feet occasionally
to 9 feet.
.MONDAY NIGHT...Northwest winds 15 to 25 knots. Waves subsiding
to 2 to 4 feet.
.TUESDAY...Northwest winds 10 to 20 knots diminishing to 5 to
15 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.TUESDAY NIGHT...North winds 5 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...North winds 5 to 15 knots veering southeast. Waves
calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots becoming south 20 to
30 knots. A chance of showers, then showers likely. Waves
building to 3 to 5 feet occasionally to 7 feet.

$$

LSZ264-122000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
401 AM EDT Sun Oct 12 2025

...GALE WARNING IN EFFECT FROM THIS AFTERNOON THROUGH MONDAY
MORNING...

.EARLY THIS MORNING...South winds 10 to 20 knots. Waves 3 to
5 feet occasionally to 7 feet.
.TODAY...South winds 15 to 25 knots increasing to 20 to 30 knots
in the afternoon, then becoming southeast gales to 35 knots late.
Waves building to 6 to 9 feet occasionally to 11 feet.
.TONIGHT...Southeast gales to 35 knots veering south after
midnight, then diminishing to 20 to 30 knots late. A chance of
showers through midnight, then showers likely after midnight.
Waves building to 8 to 11 feet occasionally to 14 feet, then
subsiding to 5 to 8 feet occasionally to 10 feet.
.MONDAY...Southwest winds 20 to 30 knots veering west in the
afternoon. A chance of showers through early afternoon. Waves
subsiding to 3 to 6 feet occasionally to 8 feet, then building to
4 to 7 feet occasionally to 9 feet.
.MONDAY NIGHT...Northwest winds 15 to 25 knots. Waves subsiding
to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...Northwest winds 15 to 25 knots diminishing to 10 to
20 knots by mid afternoon. Waves subsiding to 1 to 3 feet.
.TUESDAY NIGHT...North winds 5 to 15 knots. Waves subsiding to
calm to 2 feet.
.WEDNESDAY...Northwest winds 5 to 15 knots backing west. Waves
calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots becoming south 20 to
30 knots. A chance of showers, then showers likely. Waves
building to 4 to 7 feet occasionally to 9 feet.

$$

LSZ265-122000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
401 AM EDT Sun Oct 12 2025

...GALE WARNING IN EFFECT FROM THIS AFTERNOON THROUGH MONDAY
MORNING...

.EARLY THIS MORNING...South winds 15 to 25 knots. Waves 2 to
4 feet.
.TODAY...South winds 20 to 30 knots backing southeast in the
afternoon, then increasing to gales to 35 knots late. Waves
building to 3 to 6 feet occasionally to 8 feet.
.TONIGHT...South gales to 35 knots diminishing to 20 to 30 knots
late. A slight chance of showers through midnight, then showers
likely after midnight. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.MONDAY...Southwest winds 15 to 25 knots veering west in the
afternoon. Showers likely through early afternoon, then a slight
chance of showers by mid afternoon. Waves subsiding to 1 to
3 feet.
.MONDAY NIGHT...West winds 15 to 25 knots becoming northwest
20 to 30 knots after midnight. Waves building to 2 to 4 feet.
.TUESDAY...Northwest winds 20 to 30 knots diminishing to 15 to
25 knots by mid afternoon. Waves subsiding to 1 to 3 feet.
.TUESDAY NIGHT...North winds 10 to 20 knots. Waves subsiding to
calm to 2 feet.
.WEDNESDAY...Northwest winds 5 to 15 knots. Waves calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots becoming south 20 to
30 knots. A chance of showers, then showers likely. Waves
building to 2 to 4 feet.

$$

LSZ266-122000-
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-
401 AM EDT Sun Oct 12 2025

...GALE WARNING IN EFFECT FROM THIS AFTERNOON THROUGH MONDAY
MORNING...

.EARLY THIS MORNING...South winds 15 to 25 knots. Waves 2 to
4 feet building to 3 to 5 feet occasionally to 7 feet.
.TODAY...South winds 15 to 25 knots increasing to 20 to 30 knots
in the afternoon, then backing southeast late. Waves building to
5 to 8 feet occasionally to 10 feet.
.TONIGHT...South gales to 35 knots diminishing to 20 to 30 knots
late. A chance of showers. Waves building to 7 to 10 feet
occasionally to 13 feet, then subsiding to 5 to 8 feet
occasionally to 10 feet.
.MONDAY...South winds 15 to 25 knots veering west late. Showers
likely through early afternoon, then a chance of showers by mid
afternoon. Waves subsiding to 3 to 6 feet occasionally to 8 feet.
.MONDAY NIGHT...Northwest winds 15 to 25 knots. Waves 3 to 6 feet
occasionally to 8 feet.
.TUESDAY...Northwest winds 20 to 30 knots diminishing to 15 to
25 knots by mid afternoon. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.TUESDAY NIGHT...North winds 10 to 20 knots. Waves subsiding to
1 to 3 feet.
.WEDNESDAY...Northwest winds 5 to 15 knots. Waves subsiding to
calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots becoming south 20 to
30 knots. Showers likely. Waves building to 4 to 7 feet
occasionally to 9 feet.

$$

LSZ267-122000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 AM EDT Sun Oct 12 2025

.EARLY THIS MORNING...Southeast winds 15 to 25 knots. Waves 1 to
3 feet.
.TODAY...Southeast winds 15 to 25 knots increasing to 20 to
30 knots late. Waves building to 3 to 5 feet occasionally to
7 feet.
.TONIGHT...Southeast winds 20 to 30 knots veering south late. A
chance of showers after midnight. Waves building to 3 to 6 feet
occasionally to 8 feet.
.MONDAY...South winds 20 to 30 knots diminishing to 15 to
25 knots in the afternoon, then becoming west 10 to 20 knots
late. Showers. Waves subsiding to 1 to 3 feet.
.MONDAY NIGHT...Northwest winds 10 to 20 knots increasing to
15 to 25 knots after midnight. A slight chance of showers through
midnight. Waves building to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...Northwest winds 20 to 30 knots diminishing to 15 to
25 knots by mid afternoon. Waves 3 to 6 feet occasionally to
8 feet.
.TUESDAY NIGHT...North winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Waves subsiding to 1 to 3 feet.
.WEDNESDAY...Northwest winds 10 to 20 knots veering north. Waves
subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 5 to 15 knots increasing to 15 to
25 knots. Showers likely. Waves building to 3 to 5 feet
occasionally to 7 feet.

$$

LSZ261-121400-
MAFOR 1209/
Superior West 12430 12320 12330 12446. Waves 2 to 4 feet today.
Waves 2 to 4 feet building to 3 to 6 feet tonight.

Superior North Central...GALE WARNING IN EFFECT...12430 11440
11340 12350 11450 11456. Waves 3 to 5 feet building to 5 to 8
feet today. Waves 7 to 11 feet tonight.

Superior South Central...GALE WARNING IN EFFECT...12430 11440
12340 13450. A chance of showers overnight. Waves 2 to 4 feet
building to 3 to 5 feet today. Waves 3 to 6 feet tonight.

Superior East...GALE WARNING IN EFFECT...11420 11320 13330 12340
11440. Waves 2 to 4 feet building to 3 to 5 feet today. Waves 3
to 6 feet building to 5 to 7 feet tonight.

$$

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