074
FZUS63 KMQT 240156
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
956 PM EDT Sun Aug 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...

This evening, a 29.6 inch low is along the Quebec/Ontario line while
30.0 inch high pressure extends from Hudson Bay to Missouri. Little
movement is expected with only a slight weakening of both pressure
centers through tonight. By Monday night, the low weakens to 29.8
inches as it fully moves into Quebec, allowing the high to also
weaken to 30.0 inches and settle over the Upper Great Lakes.
Meanwhile, 29.8 inch low pressure moves over Lake Winnipeg. These
systems all shift east slowly through Wednesday afternoon, when the
weak high moves over New England as the 29.7 inch low moves over
Lake Superior. By Thursday afternoon, the low will deepen to 29.6
inches over western Quebec as a 30.2 inch high moves over northern
Manitoba. This high will extend 30.1 inch ridging over Lake Superior
Friday into the weekend.



LSZ162-240800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
956 PM EDT Sun Aug 23 2026 /856 PM CDT Sun Aug 23 2026/

.REST OF TONIGHT...West winds 5 to 15 knots veering north after
midnight. Waves calm to 2 feet.
.MONDAY...North winds 5 to 15 knots veering south in the
afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...Southeast winds 5 to 15 knots diminishing to less
than 10 knots after midnight, then backing east late. A slight
chance of showers after midnight. Waves calm to 2 feet.
.TUESDAY...South winds 5 to 15 knots backing east by mid
afternoon. A slight chance of showers through early afternoon. A
chance of thunderstorms. Showers likely by mid afternoon. Waves
calm to 2 feet.
.TUESDAY NIGHT...East winds 5 to 15 knots veering west after
midnight. Showers through midnight. A chance of thunderstorms. A
chance of showers after midnight. Waves calm to 2 feet.
.WEDNESDAY...West winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Northwest winds 10 to 20 knots. Waves calm to
2 feet.
.THURSDAY...Northwest winds 5 to 15 knots veering north. Waves
calm to 2 feet.
.FRIDAY...Northeast winds 5 to 15 knots. 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-
956 PM EDT Sun Aug 23 2026

.REST OF TONIGHT...West winds 5 to 15 knots veering northwest
after midnight. Waves calm to 2 feet.
.MONDAY...North winds 5 to 15 knots backing southwest late. Waves
calm to 2 feet.
.MONDAY NIGHT...Southwest winds 5 to 15 knots backing south late.
Waves calm to 2 feet.
.TUESDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. Showers likely and a chance of thunderstorms by mid
afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...Southeast winds 5 to 15 knots veering southwest
after midnight. Showers and a chance of thunderstorms. Waves calm
to 2 feet.
.WEDNESDAY...West winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
.WEDNESDAY NIGHT...Northwest winds 10 to 20 knots. Waves calm to
2 feet.
.THURSDAY...Northwest winds 10 to 20 knots becoming north 5 to
15 knots. Waves calm to 2 feet.
.FRIDAY...North winds 5 to 15 knots veering south. Waves calm to
2 feet.

$$

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

.REST OF TONIGHT...Northwest winds 10 to 20 knots becoming north
5 to 15 knots late. Waves 1 to 3 feet subsiding to calm to
2 feet.
.MONDAY...North winds 5 to 15 knots backing west late. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.
.MONDAY NIGHT...West winds 5 to 15 knots diminishing to less than
10 knots after midnight, then backing southwest late. Waves calm
to 2 feet.
.TUESDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. A chance of showers and a slight chance of
thunderstorms by mid afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Showers and a chance of thunderstorms. Waves
building to 1 to 3 feet.
.WEDNESDAY...Southwest winds 10 to 20 knots veering west by mid
afternoon. A chance of showers. Waves subsiding to calm to
2 feet.
.WEDNESDAY NIGHT...Northwest winds 5 to 15 knots increasing to
10 to 20 knots after midnight. Waves calm to 2 feet.
.THURSDAY...Northwest winds 10 to 20 knots becoming north 5 to
15 knots. Waves building to 1 to 3 feet, then subsiding to calm
to 2 feet.
.FRIDAY...North winds 5 to 15 knots backing southwest. Waves calm
to 2 feet.

$$

LSZ265-240800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
956 PM EDT Sun Aug 23 2026

.REST OF TONIGHT...Northwest winds 15 to 25 knots. Waves 2 to
4 feet building to 3 to 5 feet occasionally to 7 feet, then
subsiding to 2 to 4 feet.
.MONDAY...North winds 15 to 25 knots diminishing to 5 to
15 knots. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...Northwest winds 5 to 15 knots backing southwest
late. Waves calm to 2 feet.
.TUESDAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots by mid afternoon. A chance of showers and a slight
chance of thunderstorms by mid afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...South winds 15 to 25 knots. Showers and a chance
of thunderstorms. Waves building to 2 to 4 feet, then subsiding
to calm to 2 feet.
.WEDNESDAY...Southwest winds 15 to 25 knots becoming west 10 to
20 knots by mid afternoon. Showers likely through early
afternoon. A chance of showers by mid afternoon. Waves calm to
2 feet.
.WEDNESDAY NIGHT...Northwest winds 15 to 25 knots increasing to
20 to 30 knots after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.THURSDAY...Northwest winds 20 to 30 knots becoming north 10 to
20 knots. Waves building to 4 to 7 feet occasionally to 9 feet,
then subsiding to calm to 2 feet.
.FRIDAY...North winds 10 to 20 knots backing southwest. 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-
956 PM EDT Sun Aug 23 2026

.REST OF TONIGHT...Northwest winds 20 to 30 knots becoming north
15 to 25 knots after midnight. Waves 3 to 6 feet occasionally to
8 feet.
.MONDAY...North winds 15 to 25 knots backing northwest in the
afternoon, then diminishing to 10 to 20 knots late. Waves
subsiding to 1 to 3 feet.
.MONDAY NIGHT...Northwest winds 5 to 15 knots backing west late.
Waves subsiding to calm to 2 feet.
.TUESDAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots by mid afternoon. A slight chance of showers by mid
afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...Southeast winds 15 to 25 knots veering south
after midnight. A chance of showers through midnight. A chance of
thunderstorms. Showers after midnight. Waves building to 2 to
4 feet.
.WEDNESDAY...South winds 10 to 20 knots veering west by mid
afternoon. Showers through early afternoon. A chance of showers
by mid afternoon. Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...Northwest winds 15 to 25 knots increasing to
20 to 30 knots after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.THURSDAY...Northwest winds 20 to 30 knots becoming north 15 to
25 knots. Waves building to 4 to 7 feet occasionally to 9 feet,
then subsiding to calm to 2 feet.
.FRIDAY...North winds 5 to 15 knots backing west. Waves calm to
2 feet.

$$

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

.REST OF TONIGHT...Northwest winds 20 to 30 knots increasing to
30 knots with a few gale force gusts to 35 knots possible after
midnight, then becoming north 20 to 30 knots late. A slight
chance of showers by late evening. Waves 4 to 7 feet occasionally
to 9 feet subsiding to 3 to 6 feet occasionally to 8 feet.
.MONDAY...North winds 20 to 30 knots becoming northwest 15 to
25 knots in the afternoon. Waves subsiding to 2 to 4 feet.
.MONDAY NIGHT...Northwest winds 10 to 20 knots diminishing to
5 to 15 knots after midnight. Waves subsiding to calm to 2 feet.
.TUESDAY...Southwest winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...South winds 10 to 20 knots increasing to 15 to
25 knots after midnight. A chance of showers through midnight. A
slight chance of thunderstorms. Showers after midnight. Waves
building to 2 to 4 feet.
.WEDNESDAY...South winds 15 to 25 knots diminishing to 10 to
20 knots by mid afternoon. Showers and a chance of thunderstorms.
Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...West winds 10 to 20 knots veering northwest
after midnight. A chance of showers. Waves building to 1 to
3 feet.
.THURSDAY...Northwest winds 15 to 25 knots becoming north 10 to
20 knots. Waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to calm to 2 feet.
.FRIDAY...Northwest winds 10 to 20 knots diminishing to 5 to
15 knots. Waves calm to 2 feet.

$$

LSZ261-240800-
MAFOR 2403/
Superior West 11600 11700 12800 11100 13400. Waves 1 foot or
less.

Superior North Central 11720 11820 12810 12710 11610 11600. Waves
1 to 3 feet.

Superior South Central 11740 11730 11720 12830 12720 11710. Waves
3 to 5 feet overnight. Waves 2 to 4 feet Monday. Waves 1 to 3
feet Monday evening.

Superior East 11730 13830 11730 13720. Waves 3 to 6 feet
overnight and Monday. Waves 2 to 3 feet Monday 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