fzus63 kmqt 121501
glfls 
expires:202512122100;;453773

open lake forecast for lake superior
national weather service marquette mi
1000 am est fri dec 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 29.9 inch trough will move through lake superior this afternoon 
and evening while a 30.7 inch high spreads across central canada and 
the northern plains. ridging will build to 30.7 inches over the 
western lake by sunday morning as the high moves into iowa. a 30.0 
inch trough will move through the lake monday as the high settles 
into the south at 30.3 inches. a 30.1 inch ridge will move through 
lake superior monday night followed by a trough of at least 29.3 
inches tuesday night into wednesday.



lsz162-122100-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
1000 am est fri dec 12 2025 /900 am cst fri dec 12 2025/

...heavy freezing spray warning in effect from 4 pm est /3 pm
cst/ this afternoon through late saturday night...

.rest of today...west winds 15 to 25 knots becoming northwest
20 to 30 knots by mid afternoon. snow showers likely late in the
morning, then a chance of snow showers in the afternoon. waves
1 to 3 feet building to 3 to 6 feet occasionally to 8 feet. 
.tonight...northwest winds to 30 knots with a few gale force
gusts to 35 knots possible diminishing to 20 to 30 knots by
midnight. heavy freezing spray. 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. 
.saturday...northwest winds 20 to 30 knots. heavy freezing spray
in the morning. isolated snow showers. waves subsiding to 3 to
6 feet occasionally to 8 feet. 
.saturday night...northwest winds 20 to 30 knots diminishing to
15 to 25 knots after midnight. isolated snow showers. waves
subsiding to 1 to 3 feet. 
.sunday...northwest winds 10 to 20 knots backing southwest in the
afternoon. isolated snow showers in the morning. waves subsiding
to calm to 2 feet. 
.sunday night...southwest winds 20 to 30 knots. freezing spray
after midnight. a chance of snow showers after midnight. waves
building to 4 to 7 feet occasionally to 9 feet, then subsiding to
3 to 6 feet occasionally to 8 feet. 
.monday...west winds 15 to 25 knots becoming southwest 10 to
20 knots. waves subsiding to calm to 2 feet. 
.tuesday...southwest winds 20 to 30 knots veering west. waves
building to 4 to 7 feet occasionally to 9 feet, then subsiding to
2 to 4 feet. 

note, wave height forecasts are for ice free areas.

$$

fzus63 kmqt 121501
glfls 
expires:202512122100;;453774

open lake forecast for lake superior
national weather service marquette mi
1000 am est fri dec 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 29.9 inch trough will move through lake superior this afternoon 
and evening while a 30.7 inch high spreads across central canada and 
the northern plains. ridging will build to 30.7 inches over the 
western lake by sunday morning as the high moves into iowa. a 30.0 
inch trough will move through the lake monday as the high settles 
into the south at 30.3 inches. a 30.1 inch ridge will move through 
lake superior monday night followed by a trough of at least 29.3 
inches tuesday night into wednesday.



lsz263-122100-
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-
1000 am est fri dec 12 2025

...gale warning in effect from 7 pm est this evening through late
tonight...
...heavy freezing spray warning in effect from 7 pm est this
evening through sunday morning...

.rest of today...southwest winds 10 to 20 knots becoming west
20 to 30 knots by late morning, then increasing to gales to
35 knots by mid afternoon. snow showers likely late in the
morning, then a chance of snow showers in the afternoon. freezing
spray in the afternoon. waves 2 to 4 feet building to 5 to 8 feet
occasionally to 10 feet. 
.tonight...northwest gales to 35 knots diminishing to 20 to
30 knots late. heavy freezing spray. scattered snow showers.
waves building to 6 to 10 feet occasionally to 13 feet. 
.saturday...northwest winds 20 to 30 knots. heavy freezing spray.
scattered snow showers. waves subsiding to 3 to 6 feet
occasionally to 8 feet, then building to 4 to 7 feet occasionally
to 9 feet. 
.saturday night...northwest winds 20 to 30 knots diminishing to
15 to 25 knots after midnight. heavy freezing spray. scattered
snow showers. waves subsiding to 3 to 5 feet occasionally to
7 feet. 
.sunday...northwest winds 10 to 20 knots backing west in the
afternoon. scattered snow showers. waves subsiding to calm to
2 feet, then building to 1 to 3 feet. 
.sunday night...southwest winds 20 to 30 knots increasing to
gales to 35 knots after midnight. freezing spray after midnight.
a chance of snow showers after midnight. waves building to 6 to
9 feet occasionally to 11 feet. 
.monday...west winds 20 to 30 knots becoming southwest 10 to
20 knots. freezing spray. waves subsiding to calm to 2 feet. 
.tuesday...southwest gales to 35 knots becoming west 20 to
30 knots. waves building to 6 to 9 feet occasionally to 11 feet,
then subsiding to 3 to 6 feet occasionally to 8 feet. 

note, wave height forecasts are for ice free areas.

$$