514
FZUS63 KMQT 151401
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1001 AM EDT Sat Aug 15 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...

30.2 inch high pressure just north and east of Lake Superior
eventually gives way to a 29.9 inch low by tonight as the
aforementioned high moves east towards New England. This low deepens
to 29.7 inches as it reaches Quebec Sunday night. Into Monday, a
30.1 inch high over the Plains weakens to 30.0 inches as it slides
generally south of the Great Lakes Tuesday. Meanwhile Tuesday, a
29.4 inch low over Hudson Bay extends a 29.8 inch trough over Lake
Superior. Wednesday into Thursday morning, ridging of 30.1 inches
moves over the Upper Great Lakes from the Plains.



LSZ162-152000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 AM EDT Sat Aug 15 2026 /901 AM CDT Sat Aug 15 2026/

.REST OF TODAY...East winds 5 to 15 knots becoming northeast
10 to 20 knots in the afternoon. A chance of showers and a slight
chance of thunderstorms. Waves calm to 2 feet building to 1 to
3 feet.
.TONIGHT...Northeast winds 5 to 15 knots backing west late. A
chance of thunderstorms through midnight. A chance of showers.
Waves subsiding to calm to 2 feet.
.SUNDAY...West winds 10 to 20 knots diminishing to 5 to 15 knots
late. Waves calm to 2 feet.
.SUNDAY NIGHT...West winds 5 to 15 knots veering northwest after
midnight. Waves calm to 2 feet.
.MONDAY...West winds 5 to 15 knots becoming southwest 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...Southwest winds 10 to 20 knots veering west after
midnight. A chance of showers. Waves calm to 2 feet.
.TUESDAY...West winds 5 to 15 knots veering north. A chance of
showers. Waves calm to 2 feet.
.WEDNESDAY...North winds 5 to 15 knots backing northwest. Waves
calm to 2 feet.

$$

LSZ263-152000-
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 Sat Aug 15 2026

.REST OF TODAY...East winds 5 to 15 knots increasing to 10 to
20 knots late. A chance of showers. Waves calm to 2 feet.
.TONIGHT...East winds 10 to 20 knots becoming west 5 to 15 knots
after midnight. A chance of showers and thunderstorms. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.
.SUNDAY...West winds 10 to 20 knots. Waves calm to 2 feet.
.SUNDAY NIGHT...West winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...West winds 5 to 15 knots becoming southwest 15 to
25 knots by mid afternoon. Waves building to 2 to 4 feet.
.MONDAY NIGHT...Southwest winds 10 to 20 knots veering west after
midnight. A chance of showers. Waves subsiding to calm to 2 feet.
.TUESDAY...West winds 5 to 15 knots becoming north 10 to
20 knots. A chance of showers. Waves calm to 2 feet.
.WEDNESDAY...North winds 10 to 20 knots becoming northwest 5 to
15 knots. Waves calm to 2 feet.

$$

LSZ264-152000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 AM EDT Sat Aug 15 2026

.REST OF TODAY...Southeast winds 5 to 15 knots backing east late.
A chance of showers. Waves calm to 2 feet.
.TONIGHT...East winds 10 to 20 knots veering southeast after
midnight, then becoming northwest 5 to 15 knots late. Showers
likely through midnight. A slight chance of thunderstorms. A
chance of showers after midnight. Waves building to 1 to 3 feet,
then subsiding to calm to 2 feet.
.SUNDAY...Northwest winds 10 to 20 knots backing west late. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.
.SUNDAY NIGHT...West winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...West winds 5 to 15 knots becoming southwest 10 to
20 knots by mid afternoon. Waves building to 1 to 3 feet.
.MONDAY NIGHT...Southwest winds 10 to 20 knots. A chance of
showers. Waves subsiding to calm to 2 feet.
.TUESDAY...West winds 5 to 15 knots veering north. Waves calm to
2 feet.
.WEDNESDAY...North winds 10 to 20 knots becoming northwest 5 to
15 knots. Waves calm to 2 feet.

$$

LSZ265-152000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 AM EDT Sat Aug 15 2026

.REST OF TODAY...Southeast winds 10 to 20 knots backing east in
the afternoon, then increasing to 15 to 25 knots late. A slight
chance of showers by mid afternoon. Waves calm to 2 feet.
.TONIGHT...Southeast winds 15 to 25 knots becoming south 10 to
20 knots after midnight, then veering west late. Showers likely
and a slight chance of thunderstorms. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.
.SUNDAY...Northwest winds 15 to 25 knots increasing to 20 to
30 knots in the afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 2 to 4 feet.
.SUNDAY NIGHT...West winds 10 to 20 knots. Waves subsiding to
calm to 2 feet.
.MONDAY...West winds 10 to 20 knots diminishing to 5 to 15 knots
by mid afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 10 to 20 knots becoming southwest
15 to 25 knots after midnight. Waves calm to 2 feet.
.TUESDAY...West winds 10 to 20 knots veering north. A chance of
showers. Waves calm to 2 feet.
.WEDNESDAY...North winds 15 to 25 knots becoming northwest 10 to
20 knots. Waves building to 2 to 4 feet, then subsiding to calm
to 2 feet.

$$

LSZ266-152000-
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 Sat Aug 15 2026

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

$$

LSZ267-152000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 AM EDT Sat Aug 15 2026

.REST OF TODAY...Southeast winds 5 to 15 knots backing east in
the afternoon. Waves calm to 2 feet.
.TONIGHT...East winds 10 to 20 knots veering south late. A chance
of showers through midnight, then showers and a chance of
thunderstorms after midnight. Waves calm to 2 feet.
.SUNDAY...West winds 10 to 20 knots becoming northwest 15 to
25 knots in the afternoon, then increasing to 20 to 30 knots
late. A chance of showers and a slight chance of thunderstorms
through early afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet.
.SUNDAY NIGHT...Northwest winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...West winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 5 to 15 knots increasing to 10 to
20 knots after midnight. Waves calm to 2 feet.
.TUESDAY...West winds 5 to 15 knots veering north. A chance of
showers. Waves calm to 2 feet.
.WEDNESDAY...North winds 15 to 25 knots diminishing to 10 to
20 knots. A chance of showers. Waves building to 1 to 3 feet,
then subsiding to calm to 2 feet.

$$

LSZ261-152000-
MAFOR 1515/
Superior West 11210 11110 11120 11210 11110 11800 12610. A chance
of showers this afternoon. A chance of showers and thunderstorms
this evening, then a chance of showers overnight. Waves 1 to 3
feet.

Superior North Central 12310 11220 11226 11326 11420 11610 11720.
Waves 1 foot or less this afternoon. Waves 1 to 3 feet tonight
and Sunday morning.

Superior South Central 11310 12220 11330 11336 11426 11520 11730.
Waves 2 feet or less this afternoon. Waves 1 to 3 feet tonight
and Sunday morning.

Superior East 12200 12210 11320 11326 11416 11610. A chance of
thunderstorms overnight and Sunday morning. Waves 2 feet or less.

$$

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