611
FZUS63 KMQT 050801
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 AM EDT Sun Oct 5 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 29.5 inch low over eastern South Dakota will track northeast into
northern Minnesota through the morning and will reach northern
Ontario at 29.4 inches by this evening. This low will continue to
track northeast, reaching far northern Quebec as it deepens to 29.2
inches by Monday morning. This results in 29.7 inch troughing over
Lake Superior through tonight. In its wake, 30.3 inch high pressure
moving across the Northern Plains builds 30.1 inch ridging back over
Lake Superior Monday through Tuesday. The ridge strengthens to 30.4
inches over the lake on Wednesday as reinforcing high pressure moves
overhead from the Canadian Prairies. The high shifts east to New
England by Thursday night, allowing 29.8 inch troughing to return to
the lake as a 29.2 inch low moves over Hudson Bay Friday morning.


LSZ162-052000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
401 AM EDT Sun Oct 5 2025 /301 AM CDT Sun Oct 5 2025/

...GALE WARNING IN EFFECT FROM 2 PM EDT /1 PM CDT/ THIS AFTERNOON
THROUGH LATE TONIGHT...

.EARLY THIS MORNING...South winds 15 to 25 knots. Waves 3 to
5 feet occasionally to 7 feet.
.TODAY...South winds 20 to 30 knots increasing to gales to
35 knots in the afternoon, then becoming southwest gales to
40 knots late. A slight chance of showers by mid afternoon. Waves
building to 5 to 8 feet occasionally to 10 feet.
.TONIGHT...West gales to 40 knots becoming northwest 15 to
25 knots late. Waves subsiding to 1 to 3 feet.
.MONDAY...Northwest winds 10 to 20 knots backing southwest late.
Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...West winds 10 to 20 knots increasing to 15 to
25 knots after midnight. Waves building to 2 to 4 feet.
.TUESDAY...West winds 10 to 20 knots veering northwest by mid
afternoon. Waves subsiding to calm to 2 feet.
.TUESDAY NIGHT...North winds 5 to 15 knots veering northeast
after midnight. Waves calm to 2 feet.
.WEDNESDAY...Southeast winds 5 to 15 knots becoming south 10 to
20 knots. Waves building to 2 to 4 feet.
.THURSDAY...South winds 15 to 25 knots becoming southwest 10 to
20 knots. A chance of showers. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 1 to 3 feet.

$$

LSZ263-052000-
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 5 2025

...GALE WARNING IN EFFECT FROM 2 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT...

.EARLY THIS MORNING...South winds 20 to 30 knots. Waves 3 to
6 feet occasionally to 8 feet.
.TODAY...South winds 20 to 30 knots increasing to gales to
40 knots in the afternoon. A slight chance of showers and
thunderstorms by mid afternoon. Waves building to 5 to 8 feet
occasionally to 10 feet.
.TONIGHT...Southwest gales to 40 knots veering west after
midnight, then becoming northwest 20 to 30 knots late. A slight
chance of showers and thunderstorms through midnight. Waves
building to 6 to 9 feet occasionally to 11 feet, then subsiding
to 3 to 6 feet occasionally to 8 feet.
.MONDAY...Northwest winds 10 to 20 knots backing west in the
afternoon. Waves subsiding to calm to 2 feet, then building to
1 to 3 feet.
.MONDAY NIGHT...West winds 15 to 25 knots. Waves building to 3 to
6 feet occasionally to 8 feet.
.TUESDAY...West winds 15 to 25 knots veering northwest 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...Southeast winds 5 to 15 knots becoming south 15 to
25 knots. Waves building to 3 to 5 feet occasionally to 7 feet.
.THURSDAY...South winds 20 to 30 knots becoming southwest 15 to
25 knots. A chance of showers. Waves subsiding to 2 to 4 feet.

$$

LSZ264-052000-
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 5 2025

...GALE WARNING IN EFFECT FROM 2 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT...

.EARLY THIS MORNING...South winds 15 to 25 knots. Waves 3 to
6 feet occasionally to 8 feet.
.TODAY...South winds 20 to 30 knots increasing to gales to
35 knots in the afternoon. A slight chance of showers by mid
afternoon. Waves building to 5 to 8 feet occasionally to 10 feet.
.TONIGHT...Southwest gales to 35 knots veering west after
midnight, then becoming northwest 20 to 30 knots late. A slight
chance of showers and thunderstorms through midnight. Waves
building to 7 to 10 feet occasionally to 13 feet, then subsiding
to 5 to 8 feet occasionally to 10 feet.
.MONDAY...Northwest winds 15 to 25 knots becoming west 10 to
20 knots in the afternoon. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...West winds 10 to 20 knots increasing to 15 to
25 knots after midnight. Waves building to 3 to 6 feet
occasionally to 8 feet.
.TUESDAY...West winds 15 to 25 knots veering northwest by mid
afternoon. Waves subsiding to 2 to 4 feet.
.TUESDAY NIGHT...North winds 5 to 15 knots. Waves subsiding to
calm to 2 feet.
.WEDNESDAY...South winds 5 to 15 knots increasing to 15 to
25 knots. Waves building to 2 to 4 feet.
.THURSDAY...South winds 15 to 25 knots veering southwest. A
chance of showers. Waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to 2 to 4 feet.

$$

LSZ265-052000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
401 AM EDT Sun Oct 5 2025

...GALE WARNING IN EFFECT FROM 2 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT...

.EARLY THIS MORNING...South winds 15 to 25 knots. Waves 2 to
4 feet subsiding to 1 to 3 feet.
.TODAY...South winds 20 to 30 knots increasing to gales to
40 knots in the afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet.
.TONIGHT...South gales to 40 knots becoming west gales to
35 knots after midnight, then becoming northwest 20 to 30 knots
late. A slight chance of thunderstorms through midnight. A chance
of showers. Waves building to 3 to 6 feet occasionally to 8 feet,
then subsiding to 2 to 4 feet.
.MONDAY...Northwest winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then backing west late. Waves
subsiding to calm to 2 feet.
.MONDAY NIGHT...West winds 10 to 20 knots increasing to 15 to
25 knots after midnight. Waves building to 1 to 3 feet.
.TUESDAY...West winds 15 to 25 knots veering northwest by mid
afternoon. Waves building to 2 to 4 feet, then subsiding to 1 to
3 feet.
.TUESDAY NIGHT...North winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.WEDNESDAY...Southeast winds 5 to 15 knots becoming south 10 to
20 knots. Waves calm to 2 feet.
.THURSDAY...South winds 15 to 25 knots veering southwest. A
chance of showers. Waves calm to 2 feet.

$$

LSZ266-052000-
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 5 2025

...GALE WARNING IN EFFECT FROM 2 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT...

.EARLY THIS MORNING...South winds 20 to 30 knots. Waves 3 to
6 feet occasionally to 8 feet.
.TODAY...South winds 20 to 30 knots increasing to gales to
40 knots in the afternoon. Waves building to 6 to 9 feet
occasionally to 11 feet.
.TONIGHT...South gales to 40 knots becoming west gales to
35 knots after midnight, then becoming northwest 20 to 30 knots
late. A chance of showers and a slight chance of thunderstorms.
Waves building to 7 to 10 feet occasionally to 13 feet, then
subsiding to 5 to 8 feet occasionally to 10 feet.
.MONDAY...Northwest winds 15 to 25 knots diminishing to 5 to
15 knots. A slight chance of showers through early afternoon.
Waves subsiding to 2 to 4 feet.
.MONDAY NIGHT...West winds 10 to 20 knots increasing to 15 to
25 knots after midnight. A slight chance of showers through
midnight. Waves subsiding to 1 to 3 feet, then building to 3 to
5 feet occasionally to 7 feet.
.TUESDAY...West winds 15 to 25 knots veering northwest by mid
afternoon. Waves building to 3 to 6 feet occasionally to 8 feet.
.TUESDAY NIGHT...North winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. Waves subsiding to 1 to 3 feet.
.WEDNESDAY...Southeast winds 5 to 15 knots becoming south 15 to
25 knots. Waves subsiding to calm to 2 feet, then building to
2 to 4 feet.
.THURSDAY...South winds 15 to 25 knots veering southwest. A
chance of showers. Waves building to 3 to 5 feet occasionally to
7 feet.

$$

LSZ267-052000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 AM EDT Sun Oct 5 2025

.EARLY THIS MORNING...South winds 15 to 25 knots. Waves 2 to
4 feet.
.TODAY...South winds 15 to 25 knots increasing to 30 knots with a
few gale force gusts to 35 knots possible. Waves building to 5 to
8 feet occasionally to 10 feet.
.TONIGHT...South winds to 30 knots with a few gale force gusts to
35 knots possible becoming west 20 to 30 knots late. A chance of
showers through midnight. A slight chance of thunderstorms.
Showers after midnight. Waves subsiding to 4 to 8 feet
occasionally to 10 feet.
.MONDAY...Northwest winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. A slight chance of showers. Waves
subsiding to 2 to 4 feet.
.MONDAY NIGHT...West winds 10 to 20 knots. A slight chance of
showers through midnight. Waves subsiding to calm to 2 feet, then
building to 2 to 4 feet.
.TUESDAY...West winds 15 to 25 knots becoming northwest 20 to
30 knots by mid afternoon. Waves building to 4 to 7 feet
occasionally to 9 feet.
.TUESDAY NIGHT...Northwest winds 15 to 25 knots becoming north
10 to 20 knots after midnight. Waves subsiding to 1 to 3 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots veering south. Waves
subsiding to calm to 2 feet, then building to 1 to 3 feet.
.THURSDAY...South winds 15 to 25 knots. A chance of showers.
Waves building to 3 to 5 feet occasionally to 7 feet, then
subsiding to 2 to 4 feet.

$$

LSZ261-051400-
MAFOR 0509/
Superior West...GALE WARNING IN EFFECT...13440 11450 12550 11650
11640. A chance of showers this afternoon. Waves 3 to 6 feet
building to 4 to 7 feet, then subsiding to 3 to 6 feet today.
Waves 5 to 8 feet subsiding to 3 to 6 feet tonight.

Superior North Central...GALE WARNING IN EFFECT...11430 12440
13450 11550 11650. Waves 3 to 6 feet building to 4 to 7 feet
today. Waves 4 to 7 feet building to 6 to 10 feet tonight.

Superior South Central...GALE WARNING IN EFFECT...11420 11430
12440 12450 11550 11640. 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...11430 12440 13450 11456
11646. Waves 3 to 6 feet building to 5 to 7 feet today. Waves 6
to 10 feet tonight.

$$

WFO MQT

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weather.gov/mqt/glftable

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weather.gov/greatlakes