fzus63 kmqt 092101
glfls 
expires:202512100900;;295819

open lake forecast for lake superior
national weather service marquette mi
400 pm est tue dec 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...

a 29.5 inch trough of low pressure will persist over lake superior 
through wednesday morning as a 29.2 inch low currently over north 
dakota crosses southern lake michigan tonight. 29.6 to 29.7 inch 
troughing lingers over lake superior through wednesday as the low 
moves into southern quebec at 29.1 inches by wednesday night. this 
will allow 30.3 inch high pressure to rebuild over the northern 
plains late wednesday through thursday while extending weak ridging 
over lake superior. ridging breaks down slightly early friday, but 
quickly rebuilds as 30.5 inch high pressure over the northern plains 
extends back into the great lakes this weekend.



lsz162-100900-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
400 pm est tue dec 9 2025 /300 pm cst tue dec 9 2025/

.late this afternoon...east winds 10 to 20 knots. a slight chance
of snow. waves calm to 2 feet. 
.tonight...east winds 10 to 20 knots becoming northeast 20 to
30 knots by midnight. a chance of snow. freezing spray after
midnight. waves building to 6 to 9 feet occasionally to 11 feet. 
.wednesday...north winds 20 to 30 knots diminishing to 15 to
25 knots by late morning, then backing northwest by mid
afternoon. freezing spray in the morning. waves subsiding to 2 to
4 feet. 
.wednesday night...northwest winds 10 to 20 knots. waves
subsiding to calm to 2 feet. 
.thursday...northwest winds 5 to 15 knots backing west in the
afternoon. waves calm to 2 feet. 
.thursday night...west winds 5 to 15 knots increasing to 10 to
20 knots after midnight. waves calm to 2 feet. 
.friday...west winds 10 to 20 knots becoming northwest 20 to
30 knots in the afternoon. snow showers likely. waves building to
3 to 5 feet occasionally to 7 feet. 
.friday night...northwest winds 20 to 30 knots. waves building to
3 to 6 feet occasionally to 8 feet, then subsiding to 2 to
4 feet. 
.saturday...northwest winds 20 to 30 knots diminishing to 15 to
25 knots. waves subsiding to calm to 2 feet. 
.sunday...northwest winds 10 to 20 knots backing southwest. a
chance of snow showers. waves building to 2 to 4 feet. 

note, wave height forecasts are for ice free areas.

$$

fzus63 kmqt 092101
glfls 
expires:202512100900;;295820

open lake forecast for lake superior
national weather service marquette mi
400 pm est tue dec 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...

a 29.5 inch trough of low pressure will persist over lake superior 
through wednesday morning as a 29.2 inch low currently over north 
dakota crosses southern lake michigan tonight. 29.6 to 29.7 inch 
troughing lingers over lake superior through wednesday as the low 
moves into southern quebec at 29.1 inches by wednesday night. this 
will allow 30.3 inch high pressure to rebuild over the northern 
plains late wednesday through thursday while extending weak ridging 
over lake superior. ridging breaks down slightly early friday, but 
quickly rebuilds as 30.5 inch high pressure over the northern plains 
extends back into the great lakes this weekend.



lsz263-100900-
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-
400 pm est tue dec 9 2025

...gale warning in effect from 4 am est wednesday through
wednesday morning...

.late this afternoon...north winds 5 to 15 knots. waves calm to
2 feet. 
.tonight...east winds 10 to 20 knots becoming northeast 20 to
30 knots by midnight, then increasing to gales to 35 knots late.
a chance of snow. freezing spray after midnight. waves building
to 7 to 10 feet occasionally to 13 feet. 
.wednesday...north gales to 35 knots diminishing to 20 to
30 knots by late morning, then becoming northwest 15 to 25 knots
by mid afternoon. freezing spray in the morning. a slight chance
of snow showers in the morning. waves building to 8 to 11 feet
occasionally to 14 feet, then subsiding to 3 to 5 feet
occasionally to 7 feet. 
.wednesday night...northwest winds 15 to 25 knots diminishing to
10 to 20 knots by midnight, then veering north late. waves
subsiding to 2 to 4 feet. 
.thursday...northwest winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon. waves subsiding to calm to 2 feet. 
.thursday night...northwest winds 5 to 15 knots backing west
after midnight. waves calm to 2 feet. 
.friday...west winds 10 to 20 knots increasing to 20 to 30 knots
in the afternoon. a chance of snow showers in the morning, then
snow showers likely in the afternoon. freezing spray in the
afternoon. waves building to 4 to 7 feet occasionally to 9 feet. 
.friday night...northwest gales to 35 knots diminishing to 20 to
30 knots after midnight. freezing spray. a chance of snow
showers. waves building to 5 to 9 feet occasionally to 11 feet. 
.saturday...northwest winds 20 to 30 knots. heavy freezing spray.
waves subsiding to 2 to 4 feet. 
.sunday...northwest winds 15 to 25 knots backing southwest. a
chance of snow showers. waves subsiding to 1 to 3 feet, then
building to 3 to 5 feet occasionally to 7 feet. 

note, wave height forecasts are for ice free areas.

$$