966
FZUS63 KMQT 170801
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 AM EDT Sat May 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...A 29.3 inch low over us this morning leaves for the St.
Lawrence Seaway today and tonight before heading towards the
Canadian Maritimes and Maine on Sunday. Behind the departing low, a
30.4 inch high pressure moves over northern Manitoba, extending a
30.1 inch ridge over the lake by Sunday. By early Monday, this high
strengthens to 30.6 inches over far-northern Ontario and southern
Hudson Bay, with the ridge over the lake building to 30.3 inches by
Monday and remaining over Lake Superior into Tuesday. A 29.5 inch
low over the Ohio Valley Tuesday evening brings troughing of 30.0
inches back over Lake Superior by Wednesday as it splits towards the
Lower Great Lakes and Delmarva peninsula. The low then phases with
itself just off the New England coast at 29.4 inches on Thursday as
ridging of 30.1 inches moves back over Lake Superior.


LSZ162-172000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
401 AM EDT Sat May 17 2025 /301 AM CDT Sat May 17 2025/

.EARLY THIS MORNING...West winds 10 to 20 knots. A chance of rain
showers. Waves calm to 2 feet.
.TODAY...West winds 10 to 20 knots becoming northwest 15 to
25 knots in the afternoon, then diminishing to 10 to 20 knots
late. A chance of rain showers. Waves building to 1 to 3 feet,
then subsiding to calm to 2 feet.
.TONIGHT...North winds 10 to 20 knots veering northeast late. A
slight chance of rain showers. Waves calm to 2 feet.
.SUNDAY...Northeast winds 10 to 20 knots veering east in the
afternoon, then diminishing to 5 to 15 knots late. A slight
chance of rain showers through early afternoon. Waves building to
1 to 3 feet.
.SUNDAY NIGHT...Northeast winds 5 to 15 knots increasing to 10 to
20 knots after midnight. Waves subsiding to calm to 2 feet, then
building to 1 to 3 feet.
.MONDAY...Northeast winds 15 to 25 knots becoming east 20 to
30 knots by mid afternoon. Waves building to 5 to 8 feet
occasionally to 10 feet.
.MONDAY NIGHT...Northeast winds 15 to 25 knots veering east after
midnight. Waves subsiding to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...Northeast winds 20 to 30 knots diminishing to 15 to
25 knots. Waves building to 5 to 8 feet occasionally to 10 feet,
then subsiding to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots backing north. Waves
subsiding to calm to 2 feet.

$$

LSZ263-172000-
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 Sat May 17 2025

.EARLY THIS MORNING...West winds 5 to 15 knots. Patchy fog. A
chance of rain showers. Waves calm to 2 feet.
.TODAY...Northwest winds 10 to 20 knots becoming north 20 to
30 knots in the afternoon, then increasing to 30 knots with a few
gale force gusts to 35 knots possible late. Patchy fog. A chance
of rain showers. Waves building to 3 to 6 feet occasionally to
8 feet.
.TONIGHT...North winds 20 to 30 knots diminishing to 10 to
20 knots after midnight. A slight chance of rain showers. Waves
subsiding to 2 to 4 feet.
.SUNDAY...Northeast winds 10 to 20 knots diminishing to 5 to
15 knots late. A slight chance of rain and snow showers through
early afternoon. Waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to 1 to 3 feet.
.SUNDAY NIGHT...Northeast winds 5 to 15 knots increasing to 10 to
20 knots after midnight. Waves subsiding to calm to 2 feet, then
building to 1 to 3 feet.
.MONDAY...Northeast winds 15 to 25 knots. Waves building to 4 to
7 feet occasionally to 9 feet.
.MONDAY NIGHT...Northeast winds 15 to 25 knots veering east after
midnight. Waves subsiding to 2 to 4 feet, then building to 3 to
5 feet occasionally to 7 feet.
.TUESDAY...Northeast winds 20 to 30 knots diminishing to 15 to
25 knots. Waves building to 5 to 8 feet occasionally to 10 feet,
then subsiding to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots becoming north 5 to
15 knots. Waves subsiding to calm to 2 feet, then building to
1 to 3 feet.

$$

LSZ264-172000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
401 AM EDT Sat May 17 2025

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

.EARLY THIS MORNING...North winds 5 to 15 knots. Patchy fog. A
chance of rain showers. Waves 1 to 3 feet.
.TODAY...North winds 10 to 20 knots increasing to gales to
35 knots in the afternoon. Patchy fog. A chance of rain showers.
Waves building to 6 to 9 feet occasionally to 11 feet.
.TONIGHT...North winds 20 to 30 knots diminishing to 15 to
25 knots after midnight. A chance of rain showers. Waves
subsiding to 3 to 6 feet occasionally to 8 feet.
.SUNDAY...North winds 15 to 25 knots becoming northeast 10 to
20 knots in the afternoon, then backing north late. A chance of
rain showers, possibly mixed with snow. Waves subsiding to 1 to
3 feet.
.SUNDAY NIGHT...North winds 5 to 15 knots becoming northeast
10 to 20 knots after midnight. Waves subsiding to calm to 2 feet,
then building to 2 to 4 feet.
.MONDAY...Northeast winds 10 to 20 knots. Waves building to 3 to
5 feet occasionally to 7 feet, then subsiding to 1 to 3 feet.
.MONDAY NIGHT...Northeast winds 10 to 20 knots becoming east
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.TUESDAY...Northeast winds 15 to 25 knots. Waves building to 3 to
5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots becoming north 5 to
15 knots. Waves subsiding to 1 to 3 feet.

$$

LSZ265-172000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
401 AM EDT Sat May 17 2025

.EARLY THIS MORNING...West winds 10 to 20 knots. Patchy fog. A
chance of rain showers. Waves calm to 2 feet.
.TODAY...West winds 10 to 20 knots becoming northwest 15 to
25 knots in the afternoon, then increasing to 30 knots with a few
gale force gusts to 35 knots possible late. Patchy fog. A chance
of rain showers. Waves building to 4 to 7 feet occasionally to
9 feet.
.TONIGHT...Northwest winds to 30 knots with a few gale force
gusts to 35 knots possible becoming north 20 to 30 knots after
midnight, then diminishing to 15 to 25 knots late. A slight
chance of rain showers. Waves building to 5 to 8 feet
occasionally to 10 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.
.SUNDAY...North winds 15 to 25 knots. A chance of rain showers
through early afternoon. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.SUNDAY NIGHT...North winds 10 to 20 knots veering northeast
after midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...Northeast winds 15 to 25 knots diminishing to 10 to
20 knots by mid afternoon. Waves building to 2 to 4 feet, then
subsiding to 1 to 3 feet.
.MONDAY NIGHT...Northeast winds 10 to 20 knots becoming east
15 to 25 knots after midnight. Waves subsiding to calm to 2 feet,
then building to 2 to 4 feet.
.TUESDAY...Northeast winds 15 to 25 knots. Waves building to 3 to
5 feet occasionally to 7 feet, then subsiding to 1 to 3 feet.
.WEDNESDAY...North winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to 1 to 3 feet.

$$

LSZ266-172000-
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 Sat May 17 2025

...DENSE FOG ADVISORY IN EFFECT UNTIL 11 AM EDT THIS MORNING...

.EARLY THIS MORNING...Southeast winds 10 to 20 knots. Patchy fog.
A chance of rain showers. Waves 1 to 3 feet.
.TODAY...Northwest winds 10 to 20 knots increasing to 30 knots
with a few gale force gusts to 35 knots possible. Patchy fog. A
chance of rain showers. Waves subsiding to calm to 2 feet, then
building to 5 to 8 feet occasionally to 10 feet.
.TONIGHT...North winds to 30 knots with a few gale force gusts to
35 knots possible diminishing to 15 to 25 knots. A slight chance
of rain showers. Waves building to 7 to 10 feet occasionally to
13 feet, then subsiding to 3 to 6 feet occasionally to 8 feet.
.SUNDAY...North winds 15 to 25 knots. A slight chance of rain
showers. A slight chance of snow showers by mid afternoon. Waves
subsiding to 3 to 5 feet occasionally to 7 feet.
.SUNDAY NIGHT...North winds 15 to 25 knots veering northeast
after midnight. Waves subsiding to 2 to 4 feet.
.MONDAY...Northeast winds 10 to 20 knots backing north by mid
afternoon. Waves subsiding to 1 to 3 feet.
.MONDAY NIGHT...Northeast winds 10 to 20 knots. Waves building to
2 to 4 feet.
.TUESDAY...Northeast winds 10 to 20 knots increasing to 15 to
25 knots. Waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to 1 to 3 feet.
.WEDNESDAY...North winds 15 to 25 knots diminishing to 10 to
20 knots. A chance of rain showers. Waves subsiding to 2 to
4 feet.

$$

LSZ267-172000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 AM EDT Sat May 17 2025

...DENSE FOG ADVISORY IN EFFECT UNTIL 11 AM EDT THIS MORNING...

.EARLY THIS MORNING...Southeast winds 10 to 20 knots. Areas of
dense fog. A chance of rain showers. Waves calm to 2 feet.
.TODAY...Northwest winds 10 to 20 knots becoming west 15 to
25 knots late. Areas of fog. A chance of rain showers. Waves
building to 2 to 4 feet.
.TONIGHT...North winds 15 to 25 knots. Patchy fog through
midnight. A chance of rain showers through midnight. Waves
building to 3 to 6 feet occasionally to 8 feet.
.SUNDAY...North winds 15 to 25 knots. Waves subsiding to 2 to
4 feet.
.SUNDAY NIGHT...North winds 15 to 25 knots veering northeast
after midnight. Waves subsiding to 1 to 3 feet, then building to
2 to 4 feet.
.MONDAY...Northeast winds 15 to 25 knots becoming north 10 to
20 knots by mid afternoon. Waves subsiding to 1 to 3 feet.
.MONDAY NIGHT...Northeast winds 15 to 25 knots. Waves 1 to
3 feet.
.TUESDAY...Northeast winds 15 to 25 knots. Waves building to 2 to
4 feet, then subsiding to calm to 2 feet.
.WEDNESDAY...North winds 15 to 25 knots. A chance of rain
showers. Waves 2 to 4 feet.

$$

LSZ261-171400-
MAFOR 1709/
Superior West 12620 12720 11710 11810 11820 11120. A chance of
showers today. A chance of rain showers this evening. Waves 1 to
3 feet.

Superior North Central...GALE WARNING IN EFFECT...12810 11840
12850 11840 12830. A chance of rain showers today and overnight.
Waves 1 to 3 feet building to 6 to 9 feet today. Waves 5 to 9
feet subsiding to 3 to 6 feet tonight.

Superior South Central 12620 11720 11730 13740 11830. A chance of
showers today. A chance of rain showers this evening. Waves 1 to
3 feet building to 3 to 5 feet today. Waves 6 to 9 feet subsiding
to 4 to 7 feet tonight.

Superior East 11226 19224 11804 12710 11740 11840 12830. Waves 1
to 3 feet today. Waves 4 to 7 feet subsiding to 3 to 5 feet
tonight.

$$

WFO MQT

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weather.gov/mqt/glftable

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weather.gov/greatlakes