556
FZUS63 KMQT 182001
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 PM EDT Fri Sep 18 2026

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...

30.4 inch high pressure continues to track eastward, weakening to
30.2 inches as it moves into western Quebec Saturday morning.
Meanwhile, 29.9 inch low pressure develops over the Central Plains,
reaching western Iowa by Saturday morning as another 29.8 inch low
tracks across Hudson Bay. Saturday into Sunday, a 30.2 inch high
over the Canadian Prairie builds to 30.4 inches as it moves into
northwestern Ontario, creating a 30.2 inch ridging pattern over Lake
Superior. This high pressure center slowly builds to 30.5 inches as
it shifts into Quebec by midday Tuesday, trailing a 30.4 inch ridge
over Lake Superior. The high builds further to 30.6 inches Wednesday
as it progresses eastward.



LSZ162-190800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
401 PM EDT Fri Sep 18 2026 /301 PM CDT Fri Sep 18 2026/

.LATE THIS AFTERNOON...East winds 10 to 20 knots. A slight chance
of rain. Waves 1 to 3 feet building to 2 to 4 feet.
.TONIGHT...East winds 10 to 20 knots diminishing to 5 to 15 knots
after midnight. A slight chance of rain through midnight. Waves
subsiding to calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots becoming northeast 10 to
20 knots in the afternoon, then becoming east 5 to 15 knots late.
Waves calm to 2 feet.
.SATURDAY NIGHT...Northeast winds 5 to 15 knots backing north
after midnight, then becoming northeast 15 to 25 knots late.
Waves building to 1 to 3 feet.
.SUNDAY...Northeast winds 20 to 30 knots veering east 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.
.SUNDAY NIGHT...East winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...East winds 15 to 25 knots increasing to 20 to 30 knots
by mid afternoon. Waves building to 2 to 4 feet.
.MONDAY NIGHT...East winds 15 to 25 knots diminishing to 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.TUESDAY...East winds 15 to 25 knots diminishing to 10 to
20 knots. Waves calm to 2 feet.
.WEDNESDAY...East winds 10 to 20 knots diminishing to 5 to
15 knots. Waves calm to 2 feet.

$$

LSZ263-190800-
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 PM EDT Fri Sep 18 2026

.LATE THIS AFTERNOON...East winds 10 to 20 knots. Waves 1 to
3 feet.
.TONIGHT...East winds 10 to 20 knots veering southeast after
midnight, then diminishing to 5 to 15 knots late. Waves subsiding
to calm to 2 feet.
.SATURDAY...Southeast winds 5 to 15 knots backing northeast in
the afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...Northeast winds 5 to 15 knots becoming north
10 to 20 knots after midnight, then becoming northeast 15 to
25 knots late. Waves building to 1 to 3 feet.
.SUNDAY...Northeast winds 20 to 30 knots. Waves building to 4 to
7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.
.SUNDAY NIGHT...East winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...East winds 5 to 15 knots increasing to 15 to 25 knots
by mid afternoon. Waves 1 to 3 feet.
.MONDAY NIGHT...East winds 15 to 25 knots diminishing to 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.TUESDAY...East winds 10 to 20 knots veering southeast. Waves
calm to 2 feet.
.WEDNESDAY...Southeast winds 5 to 15 knots veering south. Waves
calm to 2 feet.

$$

LSZ264-190800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
401 PM EDT Fri Sep 18 2026

.LATE THIS AFTERNOON...East winds 10 to 20 knots. Waves 1 to
3 feet subsiding to calm to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. Waves calm to 2 feet.
.SATURDAY...South winds 5 to 15 knots backing southeast in the
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...East winds less than 10 knots becoming north
5 to 15 knots after midnight, then increasing to 15 to 25 knots
late. Waves calm to 2 feet.
.SUNDAY...Northeast winds 20 to 30 knots diminishing to 15 to
25 knots by mid afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 1 to 3 feet.
.SUNDAY NIGHT...Northeast winds 10 to 20 knots veering east after
midnight. Waves subsiding to calm to 2 feet, then building to
1 to 3 feet.
.MONDAY...East winds 5 to 15 knots. Waves subsiding to calm to
2 feet.
.MONDAY NIGHT...East winds 5 to 15 knots. Waves calm to 2 feet.
.TUESDAY...East winds 5 to 15 knots veering southeast. Waves calm
to 2 feet.
.WEDNESDAY...Southeast winds 5 to 15 knots veering south. Waves
calm to 2 feet.

$$

LSZ265-190800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
401 PM EDT Fri Sep 18 2026

.LATE THIS AFTERNOON...East winds 15 to 25 knots. Waves 1 to
3 feet.
.TONIGHT...East winds 15 to 25 knots becoming southeast 10 to
20 knots after midnight. Waves subsiding to calm to 2 feet.
.SATURDAY...Southeast winds 10 to 20 knots backing east late.
Waves calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots backing north after
midnight, then increasing to 15 to 25 knots late. Waves calm to
2 feet.
.SUNDAY...Northeast gales to 35 knots diminishing to 20 to
30 knots by mid afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 2 to 4 feet.
.SUNDAY NIGHT...Northeast winds 20 to 30 knots becoming east
15 to 25 knots after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.MONDAY...East winds 15 to 25 knots. Waves subsiding to 1 to
3 feet.
.MONDAY NIGHT...East winds 10 to 20 knots. Waves subsiding to
calm to 2 feet.
.TUESDAY...East winds 10 to 20 knots veering southeast. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.
.WEDNESDAY...East winds 10 to 20 knots becoming south 5 to
15 knots. Waves calm to 2 feet.

$$

LSZ266-190800-
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 PM EDT Fri Sep 18 2026

.LATE THIS AFTERNOON...East winds 5 to 15 knots. Waves 1 to
3 feet subsiding to calm to 2 feet.
.TONIGHT...East winds 5 to 15 knots veering southeast after
midnight, then increasing to 10 to 20 knots late. Waves calm to
2 feet.
.SATURDAY...Southeast winds 10 to 20 knots becoming east 5 to
15 knots late. Waves calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots backing north after
midnight, then increasing to 15 to 25 knots late. Waves calm to
2 feet.
.SUNDAY...Northeast winds 20 to 30 knots backing north by mid
afternoon. Waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to 2 to 4 feet.
.SUNDAY NIGHT...Northeast winds 15 to 25 knots veering east after
midnight. Waves building to 3 to 5 feet occasionally to 7 feet.
.MONDAY...East winds 10 to 20 knots. Waves subsiding to 1 to
3 feet.
.MONDAY NIGHT...East winds 5 to 15 knots. Waves subsiding to calm
to 2 feet, then building to 1 to 3 feet.
.TUESDAY...East winds 10 to 20 knots becoming southeast 5 to
15 knots. Waves calm to 2 feet.
.WEDNESDAY...East winds 5 to 15 knots veering southeast. Waves
calm to 2 feet.

$$

LSZ267-190800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 PM EDT Fri Sep 18 2026

.LATE THIS AFTERNOON...Northeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...East winds 5 to 15 knots veering southeast after
midnight, then increasing to 10 to 20 knots late. Waves calm to
2 feet.
.SATURDAY...Southeast winds 10 to 20 knots becoming east 5 to
15 knots late. Waves calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots backing north after
midnight. Waves calm to 2 feet.
.SUNDAY...North winds 15 to 25 knots. Waves building to 3 to
5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet.
.SUNDAY NIGHT...Northeast winds 15 to 25 knots veering east after
midnight. Waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to 2 to 4 feet.
.MONDAY...East winds 5 to 15 knots backing northeast by mid
afternoon. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...East winds 10 to 20 knots. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.
.TUESDAY...East winds 5 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...East winds 5 to 15 knots veering southeast. Waves
calm to 2 feet.

$$

LSZ261-190200-
MAFOR 1821/
Superior West 12220 12210 13200 11100. Waves 1 to 3 feet tonight.
Waves 2 feet or less Saturday.

Superior North Central 11220 14310 12410 11310. Waves 2 feet or
less.

Superior South Central 12220 11320 13310 11320 11210. Waves 1 to
3 feet.

Superior East 11100 12200 11300 13310 11300. 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