551
FZUS63 KMQT 272001
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
401 PM EDT Wed Aug 27 2025

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...

30.2 inch high pressure is centered south of the Great Lakes this
afternoon, with a weak 29.9 inch trough dropping over Lake Superior
through tonight. In its wake Thursday, a high pressure of 30.2
inches will move over the lake, residing over the lake through
Friday and at least early Saturday. Another weak 30.0 inch trough
will pass through at least northern Ontario late Saturday into
Sunday, but might stay too far north to affect the 30.2 inch high
over the Upper Great Lakes through Sunday.


LSZ162-280800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
401 PM EDT Wed Aug 27 2025 /301 PM CDT Wed Aug 27 2025/

.LATE THIS AFTERNOON...West winds 10 to 20 knots. A chance of
showers and thunderstorms. Waves 3 to 5 feet occasionally to
7 feet subsiding to 2 to 4 feet.
.TONIGHT...West winds 10 to 20 knots veering northeast after
midnight, then increasing to 15 to 25 knots late. A chance of
showers and a slight chance of thunderstorms through midnight.
Waves subsiding to calm to 2 feet, then building to 3 to 6 feet
occasionally to 8 feet.
.THURSDAY...Northeast winds 15 to 25 knots veering east in the
afternoon, then diminishing to 10 to 20 knots late. Waves
subsiding to 2 to 4 feet.
.THURSDAY NIGHT...East winds 5 to 15 knots veering southeast
late. Waves subsiding to calm to 2 feet.
.FRIDAY...South winds 5 to 15 knots. Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 5 to 15 knots veering west after
midnight. Waves calm to 2 feet.
.SATURDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.SATURDAY NIGHT...Southwest winds 5 to 15 knots veering west
after midnight. Waves calm to 2 feet.
.SUNDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.

$$

LSZ263-280800-
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 Aug 27 2025

.LATE THIS AFTERNOON...West winds 20 to 30 knots. A chance of
showers and thunderstorms. Waves 5 to 8 feet occasionally to
10 feet subsiding to 3 to 6 feet occasionally to 8 feet.
.TONIGHT...West winds 10 to 20 knots becoming northeast 15 to
25 knots after midnight. A chance of showers and a slight chance
of thunderstorms through midnight. Waves subsiding to 2 to
4 feet, then building to 3 to 6 feet occasionally to 8 feet.
.THURSDAY...Northeast winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. Waves subsiding to 2 to 4 feet.
.THURSDAY NIGHT...East winds 5 to 15 knots veering southeast
after midnight, then becoming south less than 10 knots late.
Waves subsiding to calm to 2 feet.
.FRIDAY...South winds 5 to 15 knots veering southwest by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots veering southwest after
midnight. Waves calm to 2 feet.
.SATURDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.SATURDAY NIGHT...Southwest winds 5 to 15 knots. Waves calm to
2 feet.
.SUNDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south. Waves calm
to 2 feet.

$$

LSZ264-280800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
401 PM EDT Wed Aug 27 2025

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

$$

LSZ265-280800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
401 PM EDT Wed Aug 27 2025

.LATE THIS AFTERNOON...West winds 15 to 25 knots. A chance of
showers and a slight chance of thunderstorms. Waves 3 to 5 feet
occasionally to 7 feet.
.TONIGHT...West winds 15 to 25 knots veering northeast after
midnight, then increasing to 20 to 30 knots late. A chance of
showers and a slight chance of thunderstorms through midnight.
Waves subsiding to 1 to 3 feet, then building to 5 to 8 feet
occasionally to 10 feet.
.THURSDAY...Northeast winds 20 to 30 knots diminishing to 15 to
25 knots in the afternoon, then becoming north 10 to 20 knots
late. Waves subsiding to 3 to 5 feet occasionally to 7 feet.
.THURSDAY NIGHT...North winds 5 to 15 knots veering northeast
after midnight, then backing north late. Waves subsiding to calm
to 2 feet.
.FRIDAY...West winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots veering southwest after
midnight. Waves calm to 2 feet.
.SATURDAY...West winds 5 to 15 knots backing southwest by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...Southwest winds 5 to 15 knots. Waves calm to
2 feet.
.SUNDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south. Waves calm
to 2 feet.

$$

LSZ266-280800-
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 Aug 27 2025

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

$$

LSZ267-280800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
401 PM EDT Wed Aug 27 2025

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

$$

LSZ261-280200-
MAFOR 2721/
Superior West 11626 11610 11820 13130 11120 11220. A chance of
thunderstorms this evening. Waves 3 to 5 feet subsiding to 1 to 3
feet, then building to 3 to 6 feet tonight. Waves 3 to 6 feet
Thursday.

Superior North Central 11640 11720 11830 14130 11120. A chance of
showers this evening. Waves 5 to 8 feet tonight. Waves 4 to 7
feet subsiding to 3 to 6 feet Thursday.

Superior South Central 12630 11720 14130 11830. A chance of
showers tonight. Waves 3 to 6 feet building to 5 to 7 feet
tonight. Waves 5 to 8 feet Thursday.

Superior East 12620 11820 13130 12830. A chance of showers this
evening. Waves 4 to 7 feet tonight. Waves 4 to 7 feet subsiding
to 3 to 5 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