984
FZUS63 KMQT 300801
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 AM EDT Wed Sep 30 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...

A 29.2 inch low over northern Manitoba this morning deepens to 29.0
inches over Hudson Bay this afternoon, sending a 29.7 inch trough
over Lake Superior today. 29.8 inch troughing lingers over the lake
through Thursday morning between the Canadian low and another 29.7
low over the South Plains. High pressure builds to 30.3 inches over
the northern Plains Thursday night into Friday before shifting east
to the Great Lakes Friday night and Saturday. A weak 29.9 inch
trough crosses Lake Superior Saturday night and Sunday, with 30.3
inch high pressure quickly returning Sunday night into Monday.



LSZ162-302000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
401 AM EDT Wed Sep 30 2026 /301 AM CDT Wed Sep 30 2026/

.EARLY THIS MORNING...Southwest winds 10 to 20 knots. Waves 1 to
3 feet subsiding to calm to 2 feet.
.TODAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots late. Waves building to 1 to 3 feet, then subsiding to
calm to 2 feet.
.TONIGHT...West winds 5 to 15 knots becoming northwest 10 to
20 knots late. Waves calm to 2 feet.
.THURSDAY...Northwest winds 10 to 20 knots becoming west 15 to
25 knots in the afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Northwest winds 10 to 20 knots. Waves calm to
2 feet.
.FRIDAY...Northwest winds 10 to 20 knots becoming west 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...West winds 5 to 15 knots becoming southwest less
than 10 knots after midnight. Waves calm to 2 feet.
.SATURDAY...Southwest winds 5 to 15 knots becoming west 10 to
20 knots. A chance of showers. Waves calm to 2 feet.
.SUNDAY...Northwest winds 15 to 25 knots diminishing to 5 to
15 knots. Waves calm to 2 feet.

$$

LSZ263-302000-
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 Wed Sep 30 2026

.EARLY THIS MORNING...Southwest winds 10 to 20 knots. Waves 2 to
4 feet subsiding to 1 to 3 feet.
.TODAY...Southwest winds 10 to 20 knots increasing to 15 to
25 knots in the afternoon, then becoming west 10 to 20 knots
late. Waves building to 2 to 4 feet, then subsiding to 1 to
3 feet.
.TONIGHT...Southwest winds 5 to 15 knots veering northwest late.
Waves subsiding to calm to 2 feet, then building to 1 to 3 feet.
.THURSDAY...Northwest winds 5 to 15 knots becoming west 10 to
20 knots in the afternoon, then increasing to 15 to 25 knots
late. Waves subsiding to calm to 2 feet, then building to 1 to
3 feet.
.THURSDAY NIGHT...Northwest winds 10 to 20 knots increasing to
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.FRIDAY...Northwest winds 15 to 25 knots becoming west 10 to
20 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...West winds 5 to 15 knots backing southwest after
midnight. Waves calm to 2 feet.
.SATURDAY...Southwest winds 10 to 20 knots becoming west 15 to
25 knots. A chance of showers. Waves building to 2 to 4 feet.
.SUNDAY...Northwest winds 20 to 30 knots diminishing to 10 to
20 knots. Waves subsiding to 1 to 3 feet.

$$

LSZ264-302000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
401 AM EDT Wed Sep 30 2026

.EARLY THIS MORNING...Southwest winds 10 to 20 knots. Waves 2 to
4 feet.
.TODAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots late. Waves subsiding to 1 to 3 feet, then building to
2 to 4 feet.
.TONIGHT...Southwest winds 5 to 15 knots veering northwest late.
Waves subsiding to calm to 2 feet.
.THURSDAY...Northwest winds 10 to 20 knots becoming west 15 to
25 knots in the afternoon. Waves building to 2 to 4 feet.
.THURSDAY NIGHT...Northwest winds 10 to 20 knots increasing to
15 to 25 knots after midnight. Waves subsiding to 1 to 3 feet,
then building to 2 to 4 feet.
.FRIDAY...Northwest winds 15 to 25 knots backing west by mid
afternoon. Waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to 1 to 3 feet.
.FRIDAY NIGHT...West winds 5 to 15 knots. Waves subsiding to calm
to 2 feet.
.SATURDAY...Southwest winds 5 to 15 knots becoming west 15 to
25 knots. A chance of showers. Waves building to 2 to 4 feet.
.SUNDAY...Northwest gales to 35 knots diminishing to 15 to
25 knots. Waves building to 3 to 6 feet occasionally to 8 feet,
then subsiding to 1 to 3 feet.

$$

LSZ265-302000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
401 AM EDT Wed Sep 30 2026

.EARLY THIS MORNING...South winds 10 to 20 knots. Waves 1 to
3 feet.
.TODAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon. Waves subsiding to calm to 2 feet.
.TONIGHT...Southwest winds 5 to 15 knots increasing to 10 to
20 knots after midnight, then veering west late. Waves building
to 1 to 3 feet.
.THURSDAY...Northwest winds 20 to 30 knots backing west late.
Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet.
.THURSDAY NIGHT...Northwest winds 20 to 30 knots. Waves building
to 2 to 4 feet.
.FRIDAY...Northwest gales to 35 knots diminishing to 20 to
30 knots by mid afternoon. Waves building to 4 to 7 feet
occasionally to 9 feet, then subsiding to 2 to 4 feet.
.FRIDAY NIGHT...West winds 10 to 20 knots backing southwest after
midnight. Waves subsiding to calm to 2 feet.
.SATURDAY...Southwest winds 10 to 20 knots increasing to 20 to
30 knots. A chance of showers. Waves building to 1 to 3 feet.
.SUNDAY...Northwest gales to 45 knots diminishing to 20 to
30 knots. A chance of showers. Waves building to 4 to 7 feet
occasionally to 9 feet, then subsiding to 2 to 4 feet.

$$

LSZ266-302000-
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 Wed Sep 30 2026

.EARLY THIS MORNING...South winds 15 to 25 knots. A chance of
showers. Waves 3 to 5 feet occasionally to 7 feet.
.TODAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then backing south late. Waves
subsiding to 1 to 3 feet.
.TONIGHT...South winds 5 to 15 knots becoming southwest 10 to
20 knots after midnight, then veering west late. Waves subsiding
to calm to 2 feet, then building to 1 to 3 feet.
.THURSDAY...Northwest winds 15 to 25 knots increasing to 20 to
30 knots in the afternoon. Waves building to 2 to 4 feet.
.THURSDAY NIGHT...Northwest winds 15 to 25 knots. Waves subsiding
to 1 to 3 feet, then building to 2 to 4 feet.
.FRIDAY...Northwest 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.
.FRIDAY NIGHT...Northwest winds 10 to 20 knots becoming west 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.SATURDAY...Southwest winds 10 to 20 knots increasing to 20 to
30 knots. Showers likely. Waves building to 2 to 4 feet.
.SUNDAY...Northwest gales to 45 knots. A chance of showers. Waves
building to 5 to 8 feet occasionally to 10 feet, then subsiding
to 3 to 5 feet occasionally to 7 feet.

$$

LSZ267-302000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 AM EDT Wed Sep 30 2026

.EARLY THIS MORNING...South winds 15 to 25 knots. A chance of
showers. Waves 2 to 4 feet.
.TODAY...South winds 15 to 25 knots becoming southwest 10 to
20 knots in the afternoon, then backing south late. A slight
chance of showers. Waves subsiding to calm to 2 feet.
.TONIGHT...South winds 10 to 20 knots veering southwest after
midnight. Waves calm to 2 feet.
.THURSDAY...West winds 10 to 20 knots becoming northwest 15 to
25 knots in the afternoon, then increasing to 20 to 30 knots
late. Waves building to 3 to 5 feet occasionally to 7 feet, then
subsiding to 2 to 4 feet.
.THURSDAY NIGHT...Northwest winds 15 to 25 knots. Waves 2 to
4 feet.
.FRIDAY...Northwest winds 20 to 30 knots. Waves building to 5 to
9 feet occasionally to 11 feet.
.FRIDAY NIGHT...Northwest winds 10 to 20 knots becoming west 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.SATURDAY...Southwest winds 5 to 15 knots increasing to 15 to
25 knots. Showers likely. Waves building to 2 to 4 feet.
.SUNDAY...Northwest gales to 40 knots diminishing to 20 to
30 knots. A chance of showers. Waves building to 6 to 9 feet
occasionally to 11 feet, then subsiding to 3 to 5 feet
occasionally to 7 feet.

$$

LSZ261-301400-
MAFOR 3009/
Superior West 12510 11520 12510 11610 11500 11610. Waves 1 to 3
feet.

Superior North Central 12520 11530 12520 12510 11610. Waves 2 to
4 feet subsiding to 1 to 3 feet, then building to 2 to 4 feet
today. Waves 1 to 3 feet tonight.

Superior South Central 11420 11520 12510 12400 12510. Waves 2 to
4 feet subsiding to 1 foot or less today. Waves 2 feet or less
tonight.

Superior East 11430 11420 11520 11510 13410 11510. A chance of
showers early this morning. Waves 3 to 5 feet subsiding to 1 to 3
feet today. Waves 1 to 2 feet tonight.

$$

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