593
FZUS63 KMQT 231401
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1001 AM EDT Thu Jul 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...

Weak ridging of around 30.0 inches over Lake Superior this morning
will be replaced by weak 29.9 inch troughing over the northwest half
of the lake this evening into Friday. Expect troughing to deepen to
29.8 inches through Saturday as a 29.3 inch low tracks across Hudson
Bay Friday night. Weak ridging of 29.8 to 29.9 inches develops over
the lake Saturday night. A 29.5 inch Clipper low moves into the
Upper Great Lakes or Upper Midwest by Monday.



LSZ162-232000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 AM EDT Thu Jul 23 2026 /901 AM CDT Thu Jul 23 2026/

.REST OF TODAY...Southwest 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.
.TONIGHT...Southwest winds 10 to 20 knots increasing to 15 to
25 knots after midnight, then diminishing to 10 to 20 knots late.
Waves subsiding to 1 to 3 feet.
.FRIDAY...Southwest winds 10 to 20 knots backing south late.
Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...Southwest winds 15 to 25 knots. A slight chance
of showers through midnight. A chance of thunderstorms. Showers
after midnight. Waves building to 3 to 5 feet occasionally to
7 feet.
.SATURDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots by mid afternoon. A slight chance of showers and
thunderstorms through early afternoon. Waves subsiding to calm to
2 feet.
.SATURDAY NIGHT...Northeast winds 5 to 15 knots. Waves 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.

$$

LSZ263-232000-
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 AM EDT Thu Jul 23 2026

.REST OF TODAY...Southwest winds 15 to 25 knots. Waves 3 to
6 feet occasionally to 8 feet, then subsiding to 3 to 5 feet
occasionally to 7 feet.
.TONIGHT...Southwest winds 15 to 25 knots diminishing to 10 to
20 knots late. Waves subsiding to 1 to 3 feet, then building to
2 to 4 feet.
.FRIDAY...Southwest winds 15 to 25 knots backing south late.
Waves subsiding to 1 to 3 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots veering southwest
after midnight. A slight chance of showers through midnight, then
showers and a chance of thunderstorms 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. A slight chance of showers and
thunderstorms through early afternoon. Waves subsiding to calm to
2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots becoming northeast
less than 10 knots after midnight. Waves calm to 2 feet.
.SUNDAY...East winds 5 to 15 knots. A chance of showers. Waves
calm to 2 feet.
.MONDAY...Northeast winds 5 to 15 knots backing north. Waves calm
to 2 feet.

$$

LSZ264-232000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 AM EDT Thu Jul 23 2026

.REST OF TODAY...Southwest winds 15 to 25 knots. Waves 3 to
6 feet occasionally to 8 feet.
.TONIGHT...Southwest winds 10 to 20 knots. Waves subsiding to
2 to 4 feet.
.FRIDAY...Southwest winds 10 to 20 knots backing south late.
Waves subsiding to 1 to 3 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots veering southwest
after midnight. A slight chance of showers through midnight, then
showers and a chance of thunderstorms after midnight. Waves
building to 3 to 6 feet occasionally to 8 feet.
.SATURDAY...Southwest winds 10 to 20 knots becoming west 5 to
15 knots by mid afternoon. A chance of showers and a slight
chance of thunderstorms through early afternoon. Waves subsiding
to 1 to 3 feet.
.SATURDAY NIGHT...East winds less than 10 knots. Waves subsiding
to calm to 2 feet.
.SUNDAY...Southeast winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.MONDAY...Northeast winds 5 to 15 knots backing north. Waves calm
to 2 feet.

$$

LSZ265-232000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 AM EDT Thu Jul 23 2026

.REST OF TODAY...West winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. Waves 1 to 3 feet subsiding to calm to
2 feet.
.TONIGHT...Southwest winds 10 to 20 knots. Waves calm to 2 feet.
.FRIDAY...Southwest winds 10 to 20 knots backing south in the
afternoon. Waves building to 1 to 3 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots veering southwest
after midnight. Showers likely and a slight chance of
thunderstorms after midnight. Waves building to 2 to 4 feet.
.SATURDAY...Southwest winds 10 to 20 knots becoming west 5 to
15 knots by mid afternoon. A chance of showers and a slight
chance of thunderstorms. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots. Waves calm to 2 feet.
.SUNDAY...Southeast winds 5 to 15 knots becoming southwest 10 to
20 knots. Showers likely. Waves calm to 2 feet.
.MONDAY...North winds 10 to 20 knots. Waves calm to 2 feet.

$$

LSZ266-232000-
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 AM EDT Thu Jul 23 2026

.REST OF TODAY...West winds 15 to 25 knots backing southwest
late. Waves 2 to 4 feet building to 3 to 6 feet occasionally to
8 feet, then subsiding to 3 to 5 feet occasionally to 7 feet.
.TONIGHT...Southwest winds 10 to 20 knots. Waves subsiding to
1 to 3 feet, then building to 2 to 4 feet.
.FRIDAY...Southwest winds 10 to 20 knots backing south in the
afternoon, then increasing to 15 to 25 knots late. Waves
subsiding to 1 to 3 feet, then building to 2 to 4 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots. A chance of showers
and a slight chance of thunderstorms after midnight. Waves
building to 3 to 6 feet occasionally to 8 feet.
.SATURDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots by mid afternoon. Showers through early afternoon. A
slight chance of thunderstorms. A chance of showers by mid
afternoon. Waves subsiding to 1 to 3 feet.
.SATURDAY NIGHT...Northeast winds 5 to 15 knots. Waves subsiding
to calm to 2 feet.
.SUNDAY...Southeast winds 5 to 15 knots becoming south 10 to
20 knots. A chance of showers. Waves calm to 2 feet.
.MONDAY...North winds 10 to 20 knots. Waves calm to 2 feet.

$$

LSZ267-232000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 AM EDT Thu Jul 23 2026

.REST OF TODAY...West winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then backing southwest late. Waves
2 to 4 feet subsiding to 1 to 3 feet.
.TONIGHT...Southwest winds 5 to 15 knots increasing to 10 to
20 knots after midnight. Waves 1 to 3 feet.
.FRIDAY...Southwest winds 5 to 15 knots backing south in the
afternoon. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...South winds 15 to 25 knots. A slight chance of
showers after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.SATURDAY...South winds 10 to 20 knots becoming southwest 5 to
15 knots by mid afternoon. Showers through early afternoon. A
slight chance of thunderstorms. A chance of showers by mid
afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...West winds 5 to 15 knots veering north after
midnight. Waves 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...North winds 10 to 20 knots. A chance of thunderstorms.
A chance of showers. Waves calm to 2 feet.

$$

LSZ261-232000-
MAFOR 2315/
Superior West 15530 11530 11520. Waves 2 to 4 feet building to 3
to 5 feet this afternoon. Waves 2 to 4 feet subsiding to 1 to 3
feet tonight. Waves 1 to 3 feet Friday morning.

Superior North Central 12540 12530 13520 11530. Waves 3 to 6 feet
this afternoon. Waves 3 to 6 feet subsiding to 2 to 4 feet
tonight. Waves 2 to 4 feet Friday morning.

Superior South Central 11630 11620 11520 12510 13520. Waves 2 to
4 feet subsiding to 1 to 3 feet this afternoon. Waves 1 to 2 feet
tonight and Friday morning.

Superior East 11620 14510 11520 12510. Waves 2 to 4 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