400
FZUS63 KMQT 222001
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
400 PM EDT Wed Jul 22 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 30.1 inch high pressure will continue to move through the midwest
through early Friday morning. While ridging of around 30.0 inches
looks to remain over Lake Superior on Thursday, a weak 29.9 to 30.0
inch low could move over the northwestern half of the lake by
Thursday night into Friday morning. As a low around 29.3 inches
lifts from far northern Ontario into Hudson Bay Friday night into
Saturday morning, expect troughing of around 29.8 inches to move
into Lake Superior in response by Saturday morning. Troughing of at
least 29.8 inches looks to remain over the lake for the rest of the
day. While weak ridging of 29.8 to 29.9 inches develops over Lake
Superior Sunday morning, a 29.6 inch low moving in from the west
moves over the Upper Great Lakes by Monday morning.



LSZ162-230800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
400 PM EDT Wed Jul 22 2026 /300 PM CDT Wed Jul 22 2026/

.LATE THIS AFTERNOON...Southwest winds 15 to 25 knots. Waves 1 to
3 feet building to 2 to 4 feet.
.TONIGHT...Southwest winds 10 to 20 knots veering west after
midnight, then backing southwest late. Waves subsiding to calm to
2 feet.
.THURSDAY...Southwest winds 10 to 20 knots increasing to 15 to
25 knots in the afternoon. Waves building to 2 to 4 feet, then
subsiding to 1 to 3 feet.
.THURSDAY NIGHT...Southwest winds 10 to 20 knots increasing to
15 to 25 knots late. Waves subsiding to calm to 2 feet, then
building to 1 to 3 feet.
.FRIDAY...Southwest winds 15 to 25 knots. Waves building to 3 to
5 feet occasionally to 7 feet, then subsiding to 1 to 3 feet.
.FRIDAY NIGHT...Southwest winds 20 to 30 knots. A chance of
thunderstorms. Showers after midnight. Waves building to 3 to
6 feet occasionally to 8 feet.
.SATURDAY...Southwest winds 15 to 25 knots diminishing to 10 to
20 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...North winds 5 to 15 knots veering northeast
after midnight. Waves calm to 2 feet.
.SUNDAY...Northeast winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.MONDAY...North winds 5 to 15 knots veering northeast. Waves calm
to 2 feet.

$$

LSZ263-230800-
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-
400 PM EDT Wed Jul 22 2026

.LATE THIS AFTERNOON...Southwest winds 15 to 25 knots. Waves 1 to
3 feet building to 2 to 4 feet.
.TONIGHT...Southwest winds 15 to 25 knots becoming west 10 to
20 knots after midnight, then increasing to 15 to 25 knots late.
Waves subsiding to 1 to 3 feet, then building to 2 to 4 feet.
.THURSDAY...Southwest winds 15 to 25 knots. A slight chance of
showers and thunderstorms by mid afternoon. Waves building to
3 to 5 feet occasionally to 7 feet, then subsiding to 2 to
4 feet.
.THURSDAY NIGHT...Southwest winds 10 to 20 knots increasing to
15 to 25 knots after midnight. A slight chance of showers through
midnight. Waves subsiding to 1 to 3 feet, then building to 2 to
4 feet.
.FRIDAY...Southwest winds 20 to 30 knots. Waves building to 3 to
6 feet occasionally to 8 feet.
.FRIDAY NIGHT...Southwest winds 20 to 30 knots. Showers after
midnight. Waves subsiding to 2 to 4 feet, then building to 4 to
7 feet occasionally to 9 feet.
.SATURDAY...Southwest winds 20 to 30 knots becoming west 10 to
20 knots by mid afternoon. A chance of showers through early
afternoon. Waves subsiding to 1 to 3 feet.
.SATURDAY NIGHT...Northeast winds 5 to 15 knots. Waves subsiding
to calm to 2 feet.
.SUNDAY...East winds 5 to 15 knots backing northeast. A chance of
showers. Waves calm to 2 feet.
.MONDAY...Northeast winds 5 to 15 knots. Waves calm to 2 feet.

$$

LSZ264-230800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
400 PM EDT Wed Jul 22 2026

.LATE THIS AFTERNOON...West winds 10 to 20 knots. Waves calm to
2 feet building to 1 to 3 feet.
.TONIGHT...West winds 10 to 20 knots increasing to 15 to 25 knots
late. Waves building to 2 to 4 feet.
.THURSDAY...Southwest winds 15 to 25 knots. A slight chance of
showers by mid afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 2 to 4 feet.
.THURSDAY NIGHT...Southwest winds 10 to 20 knots increasing to
15 to 25 knots late. A chance of showers and a slight chance of
thunderstorms through midnight. Waves subsiding to 1 to 3 feet,
then building to 2 to 4 feet.
.FRIDAY...Southwest winds 15 to 25 knots. Waves building to 3 to
6 feet occasionally to 8 feet, then subsiding to 2 to 4 feet.
.FRIDAY NIGHT...South winds 20 to 30 knots veering southwest
after midnight. Showers after midnight. Waves building to 4 to
7 feet occasionally to 9 feet.
.SATURDAY...Southwest winds 20 to 30 knots becoming west 10 to
20 knots by mid afternoon. A chance of showers through early
afternoon. Waves subsiding to 1 to 3 feet.
.SATURDAY NIGHT...North winds 5 to 15 knots becoming northeast
less than 10 knots after midnight. Waves subsiding to calm to
2 feet.
.SUNDAY...Southeast winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.MONDAY...Northwest winds 5 to 15 knots veering north. Waves calm
to 2 feet.

$$

LSZ265-230800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
400 PM EDT Wed Jul 22 2026

.LATE THIS AFTERNOON...West winds 15 to 25 knots. Waves calm to
2 feet.
.TONIGHT...West winds 15 to 25 knots increasing to 20 to 30 knots
late. Waves building to 1 to 3 feet.
.THURSDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...Southwest winds 10 to 20 knots increasing to
15 to 25 knots after midnight. Waves building to 1 to 3 feet.
.FRIDAY...Southwest winds 15 to 25 knots becoming south 10 to
20 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots becoming southwest
gales to 35 knots after midnight. A chance of showers after
midnight. Waves building to 3 to 5 feet occasionally to 7 feet.
.SATURDAY...Southwest winds 20 to 30 knots becoming west 10 to
20 knots by mid afternoon. Showers likely through early
afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...North winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. Waves calm to 2 feet.
.SUNDAY...East winds 5 to 15 knots becoming south 10 to 20 knots.
A chance of showers and thunderstorms. Waves calm to 2 feet.
.MONDAY...North winds 10 to 20 knots. Waves calm to 2 feet.

$$

LSZ266-230800-
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-
400 PM EDT Wed Jul 22 2026

.LATE THIS AFTERNOON...West winds 10 to 20 knots. Waves 2 to
4 feet.
.TONIGHT...West winds 10 to 20 knots increasing to 15 to 25 knots
late. Waves 2 to 4 feet.
.THURSDAY...West winds 15 to 25 knots becoming southwest 10 to
20 knots late. Waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to 2 to 4 feet.
.THURSDAY NIGHT...South winds 10 to 20 knots veering southwest
after midnight, then increasing to 15 to 25 knots late. A slight
chance of showers through midnight. Waves subsiding to 1 to
3 feet, then building to 2 to 4 feet.
.FRIDAY...Southwest winds 10 to 20 knots becoming south 15 to
25 knots by mid afternoon. Waves subsiding to 1 to 3 feet, then
building to 2 to 4 feet.
.FRIDAY NIGHT...South winds 20 to 30 knots increasing to gales to
35 knots after midnight. A chance of showers after midnight.
Waves building to 3 to 6 feet occasionally to 8 feet.
.SATURDAY...Southwest winds 15 to 25 knots becoming west 10 to
20 knots by mid afternoon. Showers through early afternoon. A
chance of thunderstorms. A chance of showers by mid afternoon.
Waves subsiding to 2 to 4 feet.
.SATURDAY NIGHT...North winds 5 to 15 knots. Waves subsiding to
calm to 2 feet.
.SUNDAY...East winds 5 to 15 knots becoming south 10 to 20 knots.
A chance of showers. Waves calm to 2 feet.
.MONDAY...Northwest winds 10 to 20 knots veering north. Waves
calm to 2 feet.

$$

LSZ267-230800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
400 PM EDT Wed Jul 22 2026

.LATE THIS AFTERNOON...West winds 15 to 25 knots. Waves 3 to
6 feet occasionally to 8 feet.
.TONIGHT...West winds 10 to 20 knots diminishing to 5 to 15 knots
after midnight, then backing southwest late. Waves subsiding to
1 to 3 feet.
.THURSDAY...Southwest winds 10 to 20 knots veering west in the
afternoon, then becoming southwest 5 to 15 knots late. Waves 1 to
3 feet.
.THURSDAY NIGHT...South winds 5 to 15 knots becoming southwest
10 to 20 knots after midnight. Waves subsiding to calm to 2 feet,
then building to 1 to 3 feet.
.FRIDAY...Southwest winds 5 to 15 knots backing south by mid
afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots increasing to 20 to
30 knots after midnight. Waves building to 3 to 6 feet
occasionally to 8 feet.
.SATURDAY...Southwest winds 15 to 25 knots diminishing to 5 to
15 knots by mid afternoon. Showers and a chance of thunderstorms.
Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...Northwest winds 5 to 15 knots. Waves calm to
2 feet.
.SUNDAY...Northwest winds 5 to 15 knots becoming south 10 to
20 knots. A chance of showers. Waves calm to 2 feet.
.MONDAY...Northwest winds 10 to 20 knots. Waves calm to 2 feet.

$$

LSZ261-230200-
MAFOR 2221/
Superior West 12530 13520 13530. Waves 1 to 3 feet tonight. Waves
1 to 3 feet building to 2 to 4 feet Thursday.

Superior North Central 12630 12620 11520 13530. Waves 2 to 4 feet
tonight. Waves 2 to 4 feet building to 3 to 5 feet Thursday.

Superior South Central 13620 14630 11620. Waves 1 to 3 feet.

Superior East 13620 13520 12510. Waves 3 to 5 feet subsiding to 2
to 3 feet tonight. Waves 2 to 4 feet Thursday.

$$

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