fzus63 kmqt 200900
glfls 
expires:202512202100;;905571

open lake forecast for lake superior
national weather service marquette mi
400 am est sat dec 20 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 low pressure of around 29.3 inches will track north of lake 
superior today. this is then followed by a 30.3 inch high over the 
canadian prairies sliding southeast into the ohio river valley late 
this weekend, building to 30.7 inches by monday morning as it 
continues towards the mid-atlantic. lake superior remains under the 
influence of this high until a weakening 29.9 inch low moves across 
the lake monday night through tuesday morning. afterwards, a 30.3 
inch high pressure moves over lake superior from the canadian 
prairies tuesday night with weak troughing of 30.0 inches moving over 
the lake on wednesday as the high shifts east.



lsz162-202100-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
400 am est sat dec 20 2025 /300 am cst sat dec 20 2025/

...gale warning in effect through late tonight...
...heavy freezing spray warning in effect from 1 pm est /noon
cst/ this afternoon through sunday morning...

.early this morning...southwest winds 20 to 30 knots. snow
showers. waves 5 to 8 feet occasionally to 10 feet. 
.today...west gales to 45 knots. heavy freezing spray. a slight
chance of snow showers. waves building to 9 to 12 feet
occasionally to 15 feet. 
.tonight...northwest gales to 40 knots diminishing to 15 to
25 knots late. a slight chance of snow showers in the evening.
heavy freezing spray. waves subsiding to 2 to 4 feet. 
.sunday...west winds 10 to 20 knots backing southwest by mid
afternoon. a slight chance of snow showers in the morning. waves
subsiding to calm to 2 feet. 
.sunday night...southwest winds 10 to 20 knots. a slight chance
of snow showers after midnight. waves calm to 2 feet. 
.monday...south winds 10 to 20 knots backing southeast in the
afternoon. a chance of snow showers. waves calm to 2 feet. 
.monday night...south winds 10 to 20 knots veering west after
midnight. a chance of snow showers. waves calm to 2 feet. 
.tuesday...west winds 10 to 20 knots becoming south 5 to
15 knots. waves building to 1 to 3 feet, then subsiding to calm
to 2 feet. 
.wednesday...south winds 5 to 15 knots. waves calm to 2 feet. 

note, wave height forecasts are for ice free areas.

$$

fzus63 kmqt 200900
glfls 
expires:202512202100;;905572

open lake forecast for lake superior
national weather service marquette mi
400 am est sat dec 20 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 low pressure of around 29.3 inches will track north of lake 
superior today. this is then followed by a 30.3 inch high over the 
canadian prairies sliding southeast into the ohio river valley late 
this weekend, building to 30.7 inches by monday morning as it 
continues towards the mid-atlantic. lake superior remains under the 
influence of this high until a weakening 29.9 inch low moves across 
the lake monday night through tuesday morning. afterwards, a 30.3 
inch high pressure moves over lake superior from the canadian 
prairies tuesday night with weak troughing of 30.0 inches moving over 
the lake on wednesday as the high shifts east.



lsz263-202100-
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 am est sat dec 20 2025

...gale warning in effect through late tonight...
...heavy freezing spray warning in effect from 1 pm est this
afternoon through sunday morning...

.early this morning...southwest winds 20 to 30 knots. snow
showers. waves 6 to 9 feet occasionally to 11 feet. 
.today...southwest gales to 40 knots becoming west gales to
45 knots. heavy freezing spray. snow showers likely in the
morning. a chance of snow showers in the afternoon. waves
building to 12 to 17 feet occasionally to 21 feet. 
.tonight...northwest gales to 45 knots diminishing to 15 to
25 knots late. heavy freezing spray. a chance of snow showers.
waves subsiding to 3 to 6 feet occasionally to 8 feet. 
.sunday...northwest winds 10 to 20 knots backing southwest by mid
afternoon. a slight chance of snow showers in the morning. waves
subsiding to 1 to 3 feet. 
.sunday night...southwest winds 10 to 20 knots. waves building to
2 to 4 feet. 
.monday...south winds 5 to 15 knots. waves subsiding to calm to
2 feet. 
.monday night...south winds 5 to 15 knots becoming west 15 to
25 knots after midnight. a chance of snow showers. waves building
to 2 to 4 feet. 
.tuesday...west winds 15 to 25 knots becoming northwest 5 to
15 knots. waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to calm to 2 feet. 
.wednesday...south winds 10 to 20 knots diminishing to 5 to
15 knots. waves calm to 2 feet. 

note, wave height forecasts are for ice free areas.

$$