609
FZUS63 KMQT 051401
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1001 AM EDT Wed Aug 5 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...

High pressure over the Plains is extending 30.0 inch ridging over
the lake this morning, which remains through Thursday. For the late
week and into the weekend, pressure over Lake Superior will remain
around 29.9 inches between a 30.3 inch Bermuda High and 29.5 inch
low pressure near the western shores of Hudson Bay. On Monday,
pressure over Lake Superior rises slightly to 30.0 inches as the
Hudson Bay low shifts east and ridging builds in from the western
provinces of Canada.



LSZ162-052000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1001 AM EDT Wed Aug 5 2026 /901 AM CDT Wed Aug 5 2026/

.REST OF TODAY...Southwest winds 5 to 15 knots backing south
late. Waves calm to 2 feet.
.TONIGHT...South winds 5 to 15 knots veering southwest late.
Waves calm to 2 feet.
.THURSDAY...Southwest winds 15 to 25 knots. Waves building to
2 to 4 feet, then subsiding to 1 to 3 feet.
.THURSDAY NIGHT...Southwest winds 15 to 25 knots. A slight chance
of showers and thunderstorms after midnight. Waves building to
2 to 4 feet.
.FRIDAY...Southwest winds 15 to 25 knots diminishing to 10 to
20 knots by mid afternoon. A chance of showers and a slight
chance of thunderstorms. Waves subsiding to calm to 2 feet.
.FRIDAY NIGHT...West winds 10 to 20 knots diminishing to 5 to
15 knots after midnight. Waves calm to 2 feet.
.SATURDAY...Southwest winds 10 to 20 knots becoming west 5 to
15 knots. Waves building to 1 to 3 feet, then subsiding to calm
to 2 feet.
.SUNDAY...Southwest winds 5 to 15 knots veering northwest. Waves
calm to 2 feet.

$$

LSZ263-052000-
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 Wed Aug 5 2026

.REST OF TODAY...Southwest winds 5 to 15 knots increasing to
10 to 20 knots in the afternoon, then backing south late. Waves
calm to 2 feet building to 1 to 3 feet.
.TONIGHT...South winds 5 to 15 knots increasing to 10 to 20 knots
after midnight, then veering southwest late. Waves subsiding to
calm to 2 feet, then building to 1 to 3 feet.
.THURSDAY...Southwest winds 15 to 25 knots increasing to 20 to
30 knots in the afternoon, then diminishing to 15 to 25 knots
late. Waves building to 3 to 5 feet occasionally to 7 feet, then
subsiding to 2 to 4 feet.
.THURSDAY NIGHT...South winds 15 to 25 knots becoming southwest
20 to 30 knots after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.FRIDAY...Southwest winds 15 to 25 knots. A slight chance of
showers through early afternoon. A slight chance of
thunderstorms. Showers likely by mid afternoon. Waves subsiding
to 1 to 3 feet.
.FRIDAY NIGHT...West winds 5 to 15 knots. Waves subsiding to calm
to 2 feet.
.SATURDAY...Southwest winds 15 to 25 knots becoming west 5 to
15 knots. Waves building to 1 to 3 feet, then subsiding to calm
to 2 feet.
.SUNDAY...Southwest winds 10 to 20 knots becoming west 5 to
15 knots. Waves calm to 2 feet.

$$

LSZ264-052000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1001 AM EDT Wed Aug 5 2026

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

$$

LSZ265-052000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1001 AM EDT Wed Aug 5 2026

.REST OF TODAY...West winds 5 to 15 knots backing east in the
afternoon. Waves calm to 2 feet.
.TONIGHT...Southeast winds 10 to 20 knots veering southwest late.
Waves calm to 2 feet.
.THURSDAY...Southwest winds 10 to 20 knots backing south in the
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 15 to 25 knots increasing to 20 to
30 knots after midnight. Waves building to 2 to 4 feet, then
subsiding to 1 to 3 feet.
.FRIDAY...South winds 10 to 20 knots. Showers likely and a slight
chance of thunderstorms by mid afternoon. Waves subsiding to calm
to 2 feet.
.FRIDAY NIGHT...West winds 10 to 20 knots. Showers likely through
midnight. Waves calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots backing southwest. Waves
calm to 2 feet.
.SUNDAY...Northwest winds 10 to 20 knots backing west. Waves calm
to 2 feet.

$$

LSZ266-052000-
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 Wed Aug 5 2026

.REST OF TODAY...West winds 5 to 15 knots backing east late.
Waves calm to 2 feet.
.TONIGHT...South winds 5 to 15 knots increasing to 10 to 20 knots
after midnight. Waves calm to 2 feet.
.THURSDAY...South winds 10 to 20 knots. Waves building to 1 to
3 feet.
.THURSDAY NIGHT...South winds 20 to 30 knots. Waves building to
3 to 5 feet occasionally to 7 feet, then subsiding to 2 to
4 feet.
.FRIDAY...South winds 10 to 20 knots. A chance of showers and a
slight chance of thunderstorms by mid afternoon. Waves subsiding
to 1 to 3 feet.
.FRIDAY NIGHT...Southwest winds 10 to 20 knots veering west after
midnight. Showers likely through midnight. Waves subsiding to
calm to 2 feet.
.SATURDAY...West winds 10 to 20 knots becoming southwest 5 to
15 knots. Waves calm to 2 feet.
.SUNDAY...West winds 5 to 15 knots. Waves calm to 2 feet.

$$

LSZ267-052000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1001 AM EDT Wed Aug 5 2026

.REST OF TODAY...Southwest winds 5 to 15 knots veering northwest
late. Waves calm to 2 feet.
.TONIGHT...South winds 5 to 15 knots. Waves calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots backing southeast late.
Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 10 to 20 knots increasing to 15 to
25 knots after midnight. Waves building to 2 to 4 feet.
.FRIDAY...South winds 10 to 20 knots. Waves subsiding to calm to
2 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots becoming west 5 to
15 knots after midnight. Showers through midnight. A chance of
thunderstorms. A chance of showers after midnight. Waves building
to 1 to 3 feet, then subsiding to calm to 2 feet.
.SATURDAY...West winds 5 to 15 knots backing southwest. Waves
calm to 2 feet.
.SUNDAY...West winds 5 to 15 knots. Waves calm to 2 feet.

$$

LSZ261-052000-
MAFOR 0515/
Superior West 11500 14410 13520. Waves 2 feet or less this
afternoon and tonight. Waves 1 to 3 feet Thursday morning.

Superior North Central 11500 11510 14410 12520. Waves 2 feet or
less this afternoon and tonight. Waves 1 to 3 feet Thursday
morning.

Superior South Central 11600 11100 11200 11310 13420 11520. Waves
2 feet or less.

Superior East 12600 11100 12400 13410. 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