874
FZUS63 KMQT 130203
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
1002 PM EDT Sat Jul 12 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...

A 29.8 inch low deepens further to 29.4 inches tonight as it drifts
northeast towards Hudson Bay while 30.0 inch high pressure builds
just south of the Great Lakes basin. The high maintains strength and
position on Sunday while the low deepens to 29.2 inches over Hudson
Bay. On Monday, weak ridging near 30.0 inches builds over Lake
Superior as 29.7 inch low pressure forms over the High Plains. This
low will pass a 29.9 inch trough over Lake Superior Tuesday before
30.1 inch high pressure builds in its wake over northern Ontario
Wednesday into Thursday.


LSZ162-130800-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
1002 PM EDT Sat Jul 12 2025 /902 PM CDT Sat Jul 12 2025/

.REST OF TONIGHT...West winds 10 to 20 knots backing southwest
after midnight, then increasing to 15 to 25 knots late. Areas of
smoke. Waves calm to 2 feet.
.SUNDAY...Southwest winds 15 to 25 knots. Areas of smoke. Waves
building to 1 to 3 feet.
.SUNDAY NIGHT...Southwest winds 15 to 25 knots becoming west
10 to 20 knots after midnight. A slight chance of showers and
thunderstorms through midnight. Areas of smoke. Waves subsiding
to calm to 2 feet.
.MONDAY...West winds 10 to 20 knots backing southwest by mid
afternoon. Areas of smoke through early afternoon. Waves calm to
2 feet.
.MONDAY NIGHT...East winds 5 to 15 knots. A chance of showers and
a slight chance of thunderstorms. Waves calm to 2 feet.
.TUESDAY...Northeast winds 10 to 20 knots. A chance of showers
through early afternoon, then showers likely by mid afternoon.
Waves calm to 2 feet.
.TUESDAY NIGHT...Northeast winds 10 to 20 knots. Showers likely
through midnight. A chance of thunderstorms. A chance of showers
after midnight. Waves calm to 2 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
.THURSDAY...Northeast winds 10 to 20 knots becoming northwest
5 to 15 knots. Waves calm to 2 feet.

$$

LSZ263-130800-
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-
1002 PM EDT Sat Jul 12 2025

.REST OF TONIGHT...West winds 10 to 20 knots. Areas of smoke.
Waves 1 to 3 feet.
.SUNDAY...Southwest winds 10 to 20 knots increasing to 15 to
25 knots in the afternoon. Areas of smoke. Waves building to 2 to
4 feet.
.SUNDAY NIGHT...Southwest winds 10 to 20 knots becoming west 5 to
15 knots late. Areas of smoke through midnight. A slight chance
of showers and thunderstorms through midnight. Waves subsiding to
1 to 3 feet.
.MONDAY...West winds 5 to 15 knots backing southwest by mid
afternoon. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...Southeast winds 5 to 15 knots. A chance of
showers. A slight chance of thunderstorms after midnight. Waves
calm to 2 feet.
.TUESDAY...South winds 5 to 15 knots. A chance of showers. Waves
calm to 2 feet.
.TUESDAY NIGHT...North winds 5 to 15 knots veering northeast
after midnight. Showers likely through midnight. A chance of
thunderstorms. A chance of showers after midnight. Waves calm to
2 feet.
.WEDNESDAY...Northeast winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.THURSDAY...Northeast winds 5 to 15 knots backing west. Waves
calm to 2 feet.

$$

LSZ264-130800-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
1002 PM EDT Sat Jul 12 2025

.REST OF TONIGHT...West winds 10 to 20 knots. Areas of smoke.
Waves calm to 2 feet building to 2 to 4 feet.
.SUNDAY...Southwest winds 10 to 20 knots. Areas of smoke. Waves
2 to 4 feet.
.SUNDAY NIGHT...Southwest winds 10 to 20 knots becoming west 5 to
15 knots late. A slight chance of showers and thunderstorms
through midnight. Areas of smoke. Waves subsiding to 1 to 3 feet.
.MONDAY...West winds 5 to 15 knots backing southwest by mid
afternoon. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...South winds 5 to 15 knots backing southeast after
midnight. A chance of showers after midnight. Waves calm to
2 feet.
.TUESDAY...South winds 5 to 15 knots. A chance of showers. Waves
calm to 2 feet.
.TUESDAY NIGHT...North winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.WEDNESDAY...Northeast winds 5 to 15 knots backing north. A
chance of showers. Waves calm to 2 feet.
.THURSDAY...North winds 5 to 15 knots backing west. Waves calm to
2 feet.

$$

LSZ265-130800-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
1002 PM EDT Sat Jul 12 2025

.REST OF TONIGHT...West winds 10 to 20 knots. Areas of smoke.
Waves calm to 2 feet.
.SUNDAY...West winds 10 to 20 knots backing south late. Areas of
smoke. Waves calm to 2 feet.
.SUNDAY NIGHT...Southwest winds 10 to 20 knots veering west late.
A slight chance of showers and thunderstorms through midnight.
Areas of smoke. Waves 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...Southeast winds 5 to 15 knots. A slight chance of
showers after midnight. Waves calm to 2 feet.
.TUESDAY...South winds 10 to 20 knots. A chance of showers and
thunderstorms. Waves calm to 2 feet.
.TUESDAY NIGHT...Northwest winds 10 to 20 knots veering north
after midnight. A chance of showers and thunderstorms. Waves calm
to 2 feet.
.WEDNESDAY...North winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
.THURSDAY...North winds 10 to 20 knots backing northwest. Waves
calm to 2 feet.

$$

LSZ266-130800-
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-
1002 PM EDT Sat Jul 12 2025

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

$$

LSZ267-130800-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
1002 PM EDT Sat Jul 12 2025

.REST OF TONIGHT...Southwest winds 10 to 20 knots veering west
late. A slight chance of showers by midnight. Areas of smoke
after midnight. Waves calm to 2 feet.
.SUNDAY...Southwest winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then becoming south 10 to 20 knots
late. Areas of smoke. Waves calm to 2 feet.
.SUNDAY NIGHT...South winds 10 to 20 knots veering southwest
after midnight. Areas of smoke. A slight chance of showers. A
slight chance of thunderstorms after midnight. Waves building to
2 to 4 feet, then subsiding to 1 to 3 feet.
.MONDAY...West winds 10 to 20 knots diminishing to 5 to 15 knots
by mid afternoon. Areas of smoke through early afternoon. A
slight chance of showers and thunderstorms through early
afternoon. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to
2 feet.
.TUESDAY...South winds 10 to 20 knots. A chance of showers. Waves
calm to 2 feet.
.TUESDAY NIGHT...Southwest winds 10 to 20 knots. A chance of
showers and thunderstorms. Waves building to 1 to 3 feet.
.WEDNESDAY...North winds 10 to 20 knots. A chance of showers and
thunderstorms. Waves subsiding to calm to 2 feet.
.THURSDAY...North winds 10 to 20 knots. Waves calm to 2 feet.

$$

LSZ261-130800-
MAFOR 1303/
Superior West 11620 11520 11620 12520 11530 12520. Waves 1 to 3
feet.

Superior North Central 11620 11520 11620 12520 11530 12520. Waves
2 to 4 feet.

Superior South Central 14620 12510 12410. Waves 2 feet or less.

Superior East 11510 12620 13510 11410 11420. Waves 1 to 3 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