309
FZUS63 KMQT 232001
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 PM EDT Wed Sep 23 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...

30.7 inch high pressure is centered over Quebec today, keeping a
30.5 inch ridge over Lake Superior along with mainly easterly winds.
The Quebec high begins to break down Thursday morning, weakening to
30.4 inches by Thursday night as winds veer southerly. By late
Friday, the high weakens to 30.2 inches over the eastern Great Lakes
basin as 29.5 inch low pressure develops over Montana. Southerly
flow persists through Saturday as the high deteriorates further and
the Montana low pressure deepens and moves north through the
Canadian Prairies. By Sunday morning, high pressure shifts
northeast, leaving pressure to 30.1 inches over Lake Superior, which
decreases to 30.0 inches by Monday morning as the high shifts toward
the Canadian Maritimes.



LSZ162-240800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
401 PM EDT Wed Sep 23 2026 /301 PM CDT Wed Sep 23 2026/

.LATE THIS AFTERNOON...Northeast winds 10 to 20 knots. Waves calm
to 2 feet building to 1 to 3 feet.
.TONIGHT...East winds 10 to 20 knots veering south after
midnight, then diminishing to 5 to 15 knots late. Waves subsiding
to calm to 2 feet, then building to 1 to 3 feet.
.THURSDAY...South winds 5 to 15 knots backing east late. A slight
chance of showers by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...East winds 5 to 15 knots becoming south less
than 10 knots after midnight. A slight chance of showers through
midnight. Waves calm to 2 feet.
.FRIDAY...South winds less than 10 knots becoming northeast 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...East winds 5 to 15 knots. Waves calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots. Waves calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots veering south after
midnight. A chance of showers. Waves calm to 2 feet.
.SUNDAY...Southwest winds 5 to 15 knots diminishing to less than
10 knots. Waves calm to 2 feet.
.MONDAY...South winds 5 to 15 knots increasing to 10 to 20 knots.
A chance of showers. Waves calm to 2 feet.

$$

LSZ263-240800-
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 Wed Sep 23 2026

.LATE THIS AFTERNOON...East winds 5 to 15 knots. Waves calm to
2 feet.
.TONIGHT...East winds 10 to 20 knots veering south after
midnight, then diminishing to 5 to 15 knots late. Waves building
to 1 to 3 feet.
.THURSDAY...South winds 5 to 15 knots backing east late. Waves
subsiding to calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.FRIDAY...Southwest winds 5 to 15 knots backing northeast by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...East winds 5 to 15 knots veering southeast after
midnight. Waves calm to 2 feet.
.SATURDAY...Southeast winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.SUNDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...South winds 5 to 15 knots increasing to 10 to 20 knots.
A chance of showers. Waves building to 1 to 3 feet.

$$

LSZ264-240800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
401 PM EDT Wed Sep 23 2026

.LATE THIS AFTERNOON...Southeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots becoming south 5 to
15 knots after midnight. Waves building to 1 to 3 feet.
.THURSDAY...South winds 5 to 15 knots backing southeast late.
Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 5 to 15 knots veering southwest
late. Waves calm to 2 feet.
.FRIDAY...Southwest winds 5 to 15 knots becoming south less than
10 knots by mid afternoon. 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...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.SUNDAY...South winds 5 to 15 knots becoming southwest less than
10 knots. Waves calm to 2 feet.
.MONDAY...South winds 5 to 15 knots increasing to 10 to 20 knots.
Waves calm to 2 feet.

$$

LSZ265-240800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
401 PM EDT Wed Sep 23 2026

.LATE THIS AFTERNOON...East winds 15 to 25 knots. Waves calm to
2 feet building to 1 to 3 feet.
.TONIGHT...Southeast winds 15 to 25 knots becoming south 10 to
20 knots after midnight. Waves subsiding to calm to 2 feet, then
building to 1 to 3 feet.
.THURSDAY...South winds 10 to 20 knots backing southeast in the
afternoon, then increasing to 15 to 25 knots late. Waves calm to
2 feet.
.THURSDAY NIGHT...Southeast winds 15 to 25 knots becoming south
10 to 20 knots after midnight, then becoming southwest 5 to
15 knots late. Waves calm to 2 feet.
.FRIDAY...Southwest winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 10 to 20 knots diminishing to
5 to 15 knots after midnight. Waves calm to 2 feet.
.SATURDAY...Southeast winds 5 to 15 knots becoming east 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. Waves calm to 2 feet.
.SUNDAY...South winds 5 to 15 knots veering west. Waves calm to
2 feet.
.MONDAY...Southeast winds 5 to 15 knots becoming south 10 to
20 knots. Waves calm to 2 feet.

$$

LSZ266-240800-
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 Wed Sep 23 2026

.LATE THIS AFTERNOON...East winds 10 to 20 knots. Waves calm to
2 feet.
.TONIGHT...Southeast winds 10 to 20 knots veering south late.
Waves building to 1 to 3 feet.
.THURSDAY...South winds 10 to 20 knots becoming southeast 5 to
15 knots in the afternoon, then becoming east 10 to 20 knots
late. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight, then diminishing to 5 to 15 knots late. Waves
calm to 2 feet.
.FRIDAY...South winds 5 to 15 knots backing east by mid
afternoon. 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 becoming east 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...Southeast winds 10 to 20 knots becoming south
5 to 15 knots after midnight. Waves calm to 2 feet.
.SUNDAY...South winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...South winds 5 to 15 knots increasing to 10 to 20 knots.
Waves building to 1 to 3 feet.

$$

LSZ267-240800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 PM EDT Wed Sep 23 2026

.LATE THIS AFTERNOON...East winds 10 to 20 knots. Waves calm to
2 feet.
.TONIGHT...Southeast winds 10 to 20 knots. Waves calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots backing east late.
Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. Waves calm to 2 feet.
.FRIDAY...South winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...East winds 5 to 15 knots veering southeast after
midnight. Waves calm to 2 feet.
.SATURDAY...Southeast winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.SUNDAY...South winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...South winds 5 to 15 knots. Waves calm to 2 feet.

$$

LSZ261-240200-
MAFOR 2321/
Superior West 11110 11220 11320 11420 12410 11400 11300. Waves 1
to 3 feet tonight. Waves 2 feet or less Thursday.

Superior North Central 12320 11310 14410 11310. Waves 1 to 3
feet.

Superior South Central 11220 12320 11420 13410 11320. Waves 1 to
3 feet.

Superior East 11210 11320 15310. Waves 1 to 2 feet.

$$

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