592
FZUS63 KMQT 121351
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
951 AM EDT Wed Mar 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...High pressure ridging of 30.0 inches over Lake
Superior, extending from a 30.2 inch surface high over Quebec,
weakens to 29.9 inches by this afternoon as a weak low lifts from
the Northern Plains into northern Ontario today into this evening.
The ridging over the lake remains through Thursday before a
deepening low pressure system drops down to 28.8 inches over
eastern Nebraska Friday evening and moves over western Lake
Superior at 29.0 inches Saturday. The low is expected to exit
across far northern Ontario through Sunday morning while troughing
averaging 29.5 inches remains over Lake Superior through much of
Sunday.


LSZ162-122200-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
951 AM EDT Wed Mar 12 2025 /851 AM CDT Wed Mar 12 2025/

.REST OF TODAY...East winds 5 to 15 knots backing northeast late.
Sprinkles and a chance of snow showers by late morning. Waves
calm to 2 feet.
.TONIGHT...East winds 5 to 15 knots veering west after midnight.
Waves calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots backing east in the
afternoon, then increasing to 10 to 20 knots late. Waves calm to
2 feet.
.THURSDAY NIGHT...East winds 10 to 20 knots. Waves building to
1 to 3 feet.
.FRIDAY...East winds 10 to 20 knots. A chance of rain showers.
Waves subsiding to calm to 2 feet, then building to 1 to 3 feet.
.FRIDAY NIGHT...East winds 10 to 20 knots increasing to 15 to
25 knots after midnight. A chance of rain showers through
midnight, then rain showers likely after midnight. Waves building
to 2 to 4 feet.
.SATURDAY...East winds 15 to 25 knots becoming northwest gales to
35 knots. Rain showers, then a chance of rain and snow showers.
Waves building to 3 to 5 feet occasionally to 7 feet, then
subsiding to 2 to 4 feet.
.SUNDAY...Northwest gales to 35 knots becoming west 15 to
25 knots. Waves building to 4 to 7 feet occasionally to 9 feet,
then subsiding to 1 to 3 feet.

$$

LSZ263-122200-
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-
951 AM EDT Wed Mar 12 2025

.REST OF TODAY...Southeast winds 5 to 15 knots backing east late.
A chance of snow showers and sprinkles by late morning. Waves
calm to 2 feet.
.TONIGHT...East winds less than 10 knots becoming southwest 5 to
15 knots after midnight, then veering west late. Waves calm to
2 feet.
.THURSDAY...Southwest winds 5 to 15 knots backing east in the
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots. Waves building
to 2 to 4 feet.
.FRIDAY...Southeast winds 10 to 20 knots becoming east 15 to
25 knots by mid afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet.
.FRIDAY NIGHT...East winds 10 to 20 knots increasing to 15 to
25 knots after midnight. A chance of rain showers. Waves building
to 4 to 7 feet occasionally to 9 feet.
.SATURDAY...East winds 15 to 25 knots becoming west gales to
35 knots. Rain showers, then a chance of rain showers, possibly
mixed with snow. Waves subsiding to 3 to 5 feet occasionally to
7 feet, then building to 5 to 8 feet occasionally to 10 feet.
.SUNDAY...Northwest gales to 40 knots becoming west gales to
35 knots. Waves building to 6 to 9 feet occasionally to 11 feet,
then subsiding to 3 to 5 feet occasionally to 7 feet.

$$

LSZ264-122200-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
951 AM EDT Wed Mar 12 2025

.REST OF TODAY...South winds 5 to 15 knots backing southeast
late. A chance of snow showers. Sprinkles by mid afternoon. Waves
calm to 2 feet building to 1 to 3 feet.
.TONIGHT...South winds 5 to 15 knots veering west late. Waves
calm to 2 feet.
.THURSDAY...West winds 5 to 15 knots backing southwest in the
afternoon, then backing southeast late. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots. Waves building
to 3 to 5 feet occasionally to 7 feet.
.FRIDAY...Southeast winds 10 to 20 knots. Waves building to 3 to
6 feet occasionally to 8 feet.
.FRIDAY NIGHT...Southeast winds 15 to 25 knots. A chance of rain
showers. Waves building to 5 to 8 feet occasionally to 10 feet.
.SATURDAY...Southeast winds 15 to 25 knots becoming west gales to
35 knots. Rain showers likely, then a chance of rain showers,
possibly mixed with snow. Waves subsiding to 3 to 6 feet
occasionally to 8 feet, then building to 5 to 8 feet occasionally
to 10 feet.
.SUNDAY...Northwest gales to 35 knots. Waves building to 7 to
10 feet occasionally to 13 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ265-122200-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
951 AM EDT Wed Mar 12 2025

.REST OF TODAY...South winds 5 to 15 knots backing southeast in
the afternoon, then increasing to 10 to 20 knots late. A chance
of snow showers by late morning. Waves calm to 2 feet.
.TONIGHT...South winds 5 to 15 knots veering west late. Waves
calm to 2 feet.
.THURSDAY...Southwest winds 5 to 15 knots backing south in the
afternoon, then becoming southeast 10 to 20 knots late. Waves
calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots. Waves building
to 2 to 4 feet.
.FRIDAY...Southeast winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet.
.FRIDAY NIGHT...Southeast winds 15 to 25 knots. A chance of rain
showers. Waves building to 3 to 6 feet occasionally to 8 feet.
.SATURDAY...Southeast winds 15 to 25 knots veering west. Rain
showers likely, then a chance of rain showers. Waves subsiding to
1 to 3 feet, then building to 3 to 6 feet occasionally to 8 feet.
.SUNDAY...Northwest gales to 35 knots becoming west 20 to
30 knots. Waves building to 5 to 8 feet occasionally to 10 feet,
then subsiding to 1 to 3 feet.

$$

LSZ266-122200-
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-
951 AM EDT Wed Mar 12 2025

.REST OF TODAY...South winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. A chance of snow showers. Waves 1 to
3 feet building to 2 to 4 feet, then subsiding to 1 to 3 feet.
.TONIGHT...South winds 10 to 20 knots becoming southwest 5 to
15 knots late. Waves 1 to 3 feet.
.THURSDAY...Southwest winds 5 to 15 knots backing south in the
afternoon, then becoming southeast 10 to 20 knots late. Waves
subsiding to calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots increasing to
15 to 25 knots after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.FRIDAY...Southeast winds 15 to 25 knots. Waves building to 3 to
6 feet occasionally to 8 feet.
.FRIDAY NIGHT...Southeast winds 20 to 30 knots. A chance of rain
showers. Waves building to 5 to 8 feet occasionally to 10 feet.
.SATURDAY...Southeast winds 15 to 25 knots becoming west 20 to
30 knots. Rain showers likely, then a chance of rain showers.
Waves subsiding to 3 to 6 feet occasionally to 8 feet, then
building to 6 to 9 feet occasionally to 11 feet.
.SUNDAY...Northwest gales to 35 knots. Waves building to 10 to
14 feet occasionally to 18 feet, then subsiding to 5 to 8 feet
occasionally to 10 feet.

$$

LSZ267-122200-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
951 AM EDT Wed Mar 12 2025

.REST OF TODAY...South winds 15 to 25 knots becoming southeast
10 to 20 knots late. Flurries by late morning. Waves 1 to 3 feet.
.TONIGHT...South winds 10 to 20 knots. Waves subsiding to calm to
2 feet.
.THURSDAY...South winds 10 to 20 knots backing southeast late.
Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots increasing to
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.FRIDAY...Southeast winds 15 to 25 knots. Waves building to 3 to
5 feet occasionally to 7 feet.
.FRIDAY NIGHT...Southeast winds 15 to 25 knots increasing to
20 to 30 knots after midnight. Waves building to 4 to 7 feet
occasionally to 9 feet.
.SATURDAY...Southeast winds 20 to 30 knots becoming south 15 to
25 knots. Rain showers, then a chance of rain showers, possibly
mixed with snow. Waves subsiding to 3 to 6 feet occasionally to
8 feet.
.SUNDAY...Northwest gales to 35 knots. A chance of rain showers.
A chance of snow showers. Waves building to 10 to 14 feet
occasionally to 18 feet, then subsiding to 5 to 8 feet
occasionally to 10 feet.

$$
LSZ261-122200-
MAFOR 1215/
Superior West 11310 11200 11100 11200 11300 12600 11400. Waves 1
foot or less.

Superior North Central 12410 11310 12410 11500 12600. Waves 2
feet or less.

Superior South Central 11420 11320 11310 11410 11420 11510 12500.
Waves 1 to 3 feet this afternoon and tonight. Waves 2 feet or
less Thursday morning.

Superior East 14420 11420 11410 11510 11500. Waves 2 to 4 feet
this afternoon. Waves 1 to 3 feet tonight and Thursday morning.

$$

LC

Experimental modernized open lake forecast is available online at
weather.gov/mqt/glftable

Graphical marine forecasts are available online at:
weather.gov/greatlakes