990
FZUS63 KMQT 180201
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1000 PM EDT Thu Sep 17 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 ridging continues to move over Lake Superior tonight into
Friday as a high presure center moves eastward across southern
Ontario. Ridging weakens to 30.1 Saturday before restrenghtening
with the southward motion and strengthening of a high pressure
center over central Ontario Sunday, reaching 30.3 inches early
Monday morning. 30.3 inch ridging remains over the area through
Wednesday next week.



LSZ162-180800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 PM EDT Thu Sep 17 2026 /901 PM CDT Thu Sep 17 2026/

.REST OF TONIGHT...North winds 5 to 15 knots becoming northeast
10 to 20 knots after midnight, then veering east late. Waves calm
to 2 feet building to 1 to 3 feet.
.FRIDAY...East winds 10 to 20 knots. A slight chance of showers
by mid afternoon. Waves 1 to 3 feet.
.FRIDAY NIGHT...East winds 10 to 20 knots. Waves subsiding to
calm to 2 feet, then building to 1 to 3 feet.
.SATURDAY...East winds 15 to 25 knots backing northeast by mid
afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...Northeast winds 5 to 15 knots increasing to
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.SUNDAY...Northeast winds 20 to 30 knots becoming east gales to
35 knots 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 20 to 30 knots diminishing to 15 to
25 knots after midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...East winds 20 to 30 knots diminishing to 15 to
25 knots. Waves building to 2 to 4 feet, then subsiding to calm
to 2 feet.
.TUESDAY...East winds 15 to 25 knots diminishing to 10 to
20 knots. Waves calm to 2 feet.

$$

LSZ263-180800-
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 Thu Sep 17 2026

.REST OF TONIGHT...North winds 5 to 15 knots becoming northeast
10 to 20 knots after midnight, then veering east late. Waves calm
to 2 feet building to 1 to 3 feet.
.FRIDAY...East winds 5 to 15 knots. Waves 1 to 3 feet.
.FRIDAY NIGHT...East winds 5 to 15 knots veering southeast after
midnight. Waves subsiding to calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots backing northeast by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...Northeast winds 5 to 15 knots increasing to
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.SUNDAY...Northeast winds 20 to 30 knots increasing to gales to
35 knots 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 20 to 30 knots diminishing to 10 to
20 knots after midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...East winds 20 to 30 knots diminishing to 15 to
25 knots. Waves subsiding to calm to 2 feet.
.TUESDAY...East winds 10 to 20 knots veering southeast. Waves
calm to 2 feet.

$$

LSZ264-180800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 PM EDT Thu Sep 17 2026

.REST OF TONIGHT...North winds 5 to 15 knots veering northeast
after midnight. Waves calm to 2 feet.
.FRIDAY...East winds 5 to 15 knots. Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to
2 feet.
.SATURDAY...Southeast winds 5 to 15 knots. Waves calm to 2 feet.
.SATURDAY NIGHT...North winds 5 to 15 knots increasing to 15 to
25 knots after midnight. Waves building to 1 to 3 feet.
.SUNDAY...Northeast winds 15 to 25 knots. 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.
.TUESDAY...East winds 5 to 15 knots veering southeast. Waves calm
to 2 feet.

$$

LSZ265-180800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 PM EDT Thu Sep 17 2026

.REST OF TONIGHT...Northwest winds 10 to 20 knots veering
northeast after midnight, then increasing to 15 to 25 knots late.
Waves calm to 2 feet.
.FRIDAY...East winds 10 to 20 knots increasing to 15 to 25 knots
late. Waves building to 1 to 3 feet.
.FRIDAY NIGHT...Southeast winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to calm to 2 feet.
.SATURDAY...Southeast winds 10 to 20 knots backing east by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots becoming north 15 to
25 knots after midnight. Waves building to 1 to 3 feet.
.SUNDAY...Northeast winds 20 to 30 knots. 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 2 to 4 feet.
.MONDAY...East winds 15 to 25 knots diminishing to 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.

$$

LSZ266-180800-
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 Thu Sep 17 2026

.REST OF TONIGHT...Northwest winds 10 to 20 knots veering north
after midnight, then becoming northeast 15 to 25 knots late.
Waves calm to 2 feet building to 1 to 3 feet.
.FRIDAY...East winds 10 to 20 knots diminishing to 5 to 15 knots
in the afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...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 by mid afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots becoming north 15 to
25 knots after midnight. 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 2 to 4 feet.
.MONDAY...East winds 10 to 20 knots. Waves subsiding to calm to
2 feet.
.TUESDAY...East winds 10 to 20 knots veering southeast. Waves
calm to 2 feet.

$$

LSZ267-180800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 PM EDT Thu Sep 17 2026

.REST OF TONIGHT...Northwest winds 10 to 20 knots veering
northeast late. Waves calm to 2 feet building to 1 to 3 feet.
.FRIDAY...Northeast winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...Northeast winds 5 to 15 knots veering southeast
after midnight. Waves calm to 2 feet.
.SATURDAY...Southeast winds 10 to 20 knots becoming east 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots backing north after
midnight. Waves calm to 2 feet.
.SUNDAY...Northeast winds 10 to 20 knots becoming north 15 to
25 knots by mid afternoon. Waves building to 2 to 4 feet.
.SUNDAY NIGHT...Northeast winds 15 to 25 knots veering east after
midnight. Waves 2 to 4 feet.
.MONDAY...East winds 5 to 15 knots increasing to 10 to 20 knots.
Waves subsiding to calm to 2 feet.
.TUESDAY...East winds 5 to 15 knots veering southeast. Waves calm
to 2 feet.

$$

LSZ261-180800-
MAFOR 1803/
Superior West 11820 11120 15220. Waves 1 to 3 feet.

Superior North Central 11820 12120 13210 12310. Waves 1 to 3
feet.

Superior South Central 11820 12120 12210 13220. Waves 1 to 3
feet.

Superior East 11810 11820 12110 11210 13100. Waves 1 to 3 feet
overnight and Friday. Waves 1 foot or less Friday evening.

$$

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