674
FZUS63 KMQT 100154
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
954 PM EDT Wed Apr 9 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...30.4 inch high pressure clipping the mid Atlantic
coast will continue to shift out into the Atlantic overnight. A
29.8 inch trough over the Northern Plains will weaken and phase
with a 29.9 inch low over central Iowa Thursday morning and then
reach the Ohio Valley Thursday evening. Ridging builds to 30.3
inches Thursday evening over the Upper Great Lakes where it
remains anchored through Saturday morning. The ridging then
weakens to 30.2 inches Saturday as 29.7 inch troughing settles in
from the west. As a 29.5 inch low organizes over the Plains this
weekend, expect troughing of 29.6 inches to track across the
western portion of Lake Superior Sunday as the low lifts into the
Northern Plains towards north Ontario. The low is expected to
reach western Lake Superior early Monday morning at 29.4 inches
and is forecast to deepen to 29.3 inches Monday evening over the
north half of Lake Superior.

LSZ162-101000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
954 PM EDT Wed Apr 9 2025 /854 PM CDT Wed Apr 9 2025/

.REST OF TONIGHT...East winds 10 to 20 knots. A chance of rain
showers, possibly mixed with snow. Waves 2 to 4 feet subsiding to
1 to 3 feet.
.THURSDAY...East winds 10 to 20 knots backing northeast in the
afternoon, then diminishing to 5 to 15 knots late. A slight
chance of rain and snow showers through early afternoon. Waves
subsiding to calm to 2 feet.
.THURSDAY NIGHT...Northeast winds 5 to 15 knots backing north
after midnight, then backing west late. Waves calm to 2 feet.
.FRIDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots. Waves calm to 2 feet.
.SATURDAY...South winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots veering southeast
after midnight. A chance of rain showers. Waves calm to 2 feet.
.SUNDAY...East winds 10 to 20 knots becoming northeast 15 to
25 knots. A chance of rain showers. Waves building to 2 to
4 feet.
.MONDAY...Northwest winds 20 to 30 knots. A chance of rain
showers. A chance of snow showers. Waves building to 3 to 6 feet
occasionally to 8 feet, then subsiding to 2 to 4 feet.

$$

LSZ263-101000-
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-
954 PM EDT Wed Apr 9 2025

.REST OF TONIGHT...East winds 5 to 15 knots. A slight chance of
rain showers. Waves 1 to 3 feet subsiding to calm to 2 feet.
.THURSDAY...East winds 5 to 15 knots backing northeast in the
afternoon. A slight chance of rain showers through early
afternoon. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...Northeast winds 5 to 15 knots becoming north
less than 10 knots after midnight, then backing west late. Waves
calm to 2 feet.
.FRIDAY...West winds 5 to 15 knots backing southwest by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots. Waves calm to 2 feet.
.SATURDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...South winds 5 to 15 knots. A chance of rain
showers after midnight. Waves building to 1 to 3 feet.
.SUNDAY...Southeast winds 10 to 20 knots increasing to 15 to
25 knots. A chance of rain showers. Waves building to 3 to 5 feet
occasionally to 7 feet.
.MONDAY...West winds 20 to 30 knots veering northwest. A chance
of rain showers. A chance of snow showers. Waves building to 4 to
8 feet occasionally to 10 feet.

$$

LSZ264-101000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
954 PM EDT Wed Apr 9 2025

.REST OF TONIGHT...Southeast winds 5 to 15 knots backing east
after midnight. Waves calm to 2 feet building to 1 to 3 feet.
.THURSDAY...Southeast winds 5 to 15 knots backing east in the
afternoon. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...East winds 5 to 15 knots becoming northwest
less than 10 knots after midnight, then backing west late. Waves
calm to 2 feet.
.FRIDAY...West winds 5 to 15 knots backing southwest by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...Southwest winds 5 to 15 knots backing south after
midnight. Waves calm to 2 feet.
.SATURDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...South winds 10 to 20 knots. Waves building to
2 to 4 feet.
.SUNDAY...Southeast winds 10 to 20 knots. A chance of rain
showers. Waves subsiding to 1 to 3 feet, then building to 3 to
6 feet occasionally to 8 feet.
.MONDAY...West winds 15 to 25 knots becoming northwest 20 to
30 knots. A chance of rain showers. A chance of snow showers.
Waves building to 4 to 7 feet occasionally to 9 feet, then
subsiding to 3 to 6 feet occasionally to 8 feet.

$$

LSZ265-101000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
954 PM EDT Wed Apr 9 2025

.REST OF TONIGHT...East winds 10 to 20 knots veering southeast
after midnight. Waves calm to 2 feet building to 1 to 3 feet,
then subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots backing east in the
afternoon, then diminishing to 5 to 15 knots late. Waves calm to
2 feet.
.THURSDAY NIGHT...East winds 5 to 15 knots backing north after
midnight, then backing northwest late. Waves 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. Waves calm to 2 feet.
.SATURDAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...South winds 10 to 20 knots. Waves calm to
2 feet.
.SUNDAY...Southeast winds 15 to 25 knots. A chance of rain
showers. Waves building to 2 to 4 feet.
.MONDAY...West winds 20 to 30 knots veering northwest. A chance
of rain showers. A chance of snow showers. Waves building to 4 to
7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ266-101000-
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-
954 PM EDT Wed Apr 9 2025

.REST OF TONIGHT...Southeast winds 10 to 20 knots. Waves calm to
2 feet building to 1 to 3 feet, then subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 5 to 15 knots becoming east 10 to
20 knots in the afternoon, then diminishing to 5 to 15 knots
late. Waves calm to 2 feet.
.THURSDAY NIGHT...Northeast winds 5 to 15 knots backing north
after midnight. Waves calm to 2 feet.
.FRIDAY...Northwest winds 5 to 15 knots. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots. Waves calm to 2 feet.
.SATURDAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...South winds 15 to 25 knots. Waves building to
2 to 4 feet.
.SUNDAY...South winds 15 to 25 knots backing southeast. A chance
of rain showers. Waves subsiding to 1 to 3 feet, then building to
3 to 6 feet occasionally to 8 feet.
.MONDAY...South winds 15 to 25 knots becoming northwest 20 to
30 knots. A chance of rain showers. A chance of snow showers.
Waves building to 5 to 8 feet occasionally to 10 feet.

$$

LSZ267-101000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
954 PM EDT Wed Apr 9 2025

.REST OF TONIGHT...Southeast winds 10 to 20 knots. Waves calm to
2 feet.
.THURSDAY...Southeast winds 10 to 20 knots becoming east 5 to
15 knots in the afternoon, then backing northeast late. Waves
calm to 2 feet.
.THURSDAY NIGHT...North winds 5 to 15 knots. Waves calm to
2 feet.
.FRIDAY...Northwest winds 5 to 15 knots. Waves calm to 2 feet.
.FRIDAY NIGHT...Northwest winds 5 to 15 knots backing southwest
after midnight. Waves calm to 2 feet.
.SATURDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.SATURDAY NIGHT...South winds 10 to 20 knots. Waves building to
1 to 3 feet.
.SUNDAY...Southeast winds 15 to 25 knots. A chance of rain
showers, then rain showers likely. Waves building to 3 to 5 feet
occasionally to 7 feet.
.MONDAY...South winds 15 to 25 knots becoming west 20 to
30 knots. A chance of rain showers. A chance of snow showers.
Waves building to 5 to 8 feet occasionally to 10 feet.

$$
LSZ261-101000-
MAFOR 1003/
Superior West 13220 11210 13110 11100. A chance of rain showers
late this evening. Waves 1 to 4 feet.

Superior North Central 14310 11310 12210 11100. Waves 1 to 3
feet.

Superior South Central 14310 11300 11210 11200 11100. Waves 1 to
3 feet.

Superior East 14310 11210 11200 11100 11800. Waves 2 feet or
less.

$$

JSS

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

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