fzus63 kmqt 152101
glfls 
expires:202512160900;;643165

open lake forecast for lake superior
national weather service marquette mi
400 pm est mon dec 15 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 over the east half of the lake this afternoon 
will exit into northeastern ontario this evening. this trough is 
then followed by a weak 30.0 inch ridge tonight. tuesday, a 29.2 
inch trough crosses the lake as the 29.0 inch parent low tracks 
across northern ontario. weak ridging of 29.9 inches then returns on 
wednesday. wednesday evening through thursday morning, a 29.0 inch 
alberta clipper tracks from the canadian prairie to western lake 
superior, weakening to 29.2 inches as it progresses. the low crosses 
the lake thursday, followed by 30.1 inch ridging on friday 
associated with a 30.2 minch high over the lower mississippi valley. 
another low pressure of around 29.5 inches tracks near the upper 
great lakes saturday with ridging to follow late in the weekend.



lsz162-160900-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
400 pm est mon dec 15 2025 /300 pm cst mon dec 15 2025/

...gale warning in effect from tuesday morning through late
tuesday night...

.late this afternoon...northwest winds 5 to 15 knots. waves calm
to 2 feet. 
.tonight...northwest winds 5 to 15 knots backing southwest by
midnight, then increasing to 15 to 25 knots late. waves building
to 3 to 5 feet occasionally to 7 feet. 
.tuesday...southwest gales to 40 knots. a slight chance of
freezing rain, snow showers and sleet in the morning. waves
building to 9 to 12 feet occasionally to 15 feet. 
.tuesday night...west gales to 40 knots becoming northwest 20 to
30 knots late. waves subsiding to 2 to 4 feet. 
.wednesday...west winds 10 to 20 knots becoming southwest 15 to
25 knots in the afternoon. a slight chance of snow showers in the
afternoon. waves subsiding to calm to 2 feet, then building to
2 to 4 feet. 
.wednesday night...south gales to 35 knots veering southwest
after midnight. a chance of rain showers, possibly mixed with
freezing rain in the evening. a chance of snow showers. rain
showers likely after midnight. waves building to 5 to 8 feet
occasionally to 10 feet. 
.thursday...north gales to 45 knots. rain showers likely in the
morning. snow showers likely. freezing spray in the afternoon.
waves building to 8 to 12 feet occasionally to 15 feet. 
.thursday night...north gales to 45 knots diminishing to 20 to
30 knots after midnight. heavy freezing spray in the evening.
waves subsiding to 1 to 3 feet. 
.friday...south winds 15 to 25 knots increasing to 20 to
30 knots. a chance of snow showers, then snow showers likely.
waves subsiding to calm to 2 feet, then building to 5 to 8 feet
occasionally to 10 feet. 
.saturday...west winds 20 to 30 knots becoming northwest 15 to
25 knots. waves subsiding to calm to 2 feet. 

note, wave height forecasts are for ice free areas.

$$

fzus63 kmqt 152101
glfls 
expires:202512160900;;643166

open lake forecast for lake superior
national weather service marquette mi
400 pm est mon dec 15 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 over the east half of the lake this afternoon 
will exit into northeastern ontario this evening. this trough is 
then followed by a weak 30.0 inch ridge tonight. tuesday, a 29.2 
inch trough crosses the lake as the 29.0 inch parent low tracks 
across northern ontario. weak ridging of 29.9 inches then returns on 
wednesday. wednesday evening through thursday morning, a 29.0 inch 
alberta clipper tracks from the canadian prairie to western lake 
superior, weakening to 29.2 inches as it progresses. the low crosses 
the lake thursday, followed by 30.1 inch ridging on friday 
associated with a 30.2 minch high over the lower mississippi valley. 
another low pressure of around 29.5 inches tracks near the upper 
great lakes saturday with ridging to follow late in the weekend.



lsz263-160900-
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 mon dec 15 2025

...gale warning in effect from tuesday morning through late
tuesday night...

.late this afternoon...northwest winds 5 to 15 knots. waves 1 to
3 feet. 
.tonight...northwest winds 5 to 15 knots becoming southwest 10 to
20 knots by midnight, then increasing to 20 to 30 knots late.
waves subsiding to calm to 2 feet, then building to 3 to 5 feet
occasionally to 7 feet. 
.tuesday...southwest gales to 40 knots. a slight chance of
freezing rain and sleet in the morning. waves building to 10 to
14 feet occasionally to 18 feet. 
.tuesday night...west gales to 40 knots becoming northwest gales
to 35 knots late. waves subsiding to 5 to 8 feet occasionally to
10 feet. 
.wednesday...west winds 15 to 25 knots backing southwest in the
afternoon. waves subsiding to 1 to 3 feet, then building to 3 to
5 feet occasionally to 7 feet. 
.wednesday night...south gales to 35 knots veering southwest
after midnight. a chance of rain showers in the evening. a chance
of snow showers. rain showers likely after midnight. waves
building to 7 to 10 feet occasionally to 13 feet. 
.thursday...north gales to 40 knots increasing to storm force
winds to 55 knots in the afternoon. rain showers likely in the
morning. snow showers likely. freezing spray in the afternoon.
waves building to 12 to 17 feet occasionally to 21 feet. 
.thursday night...north storm force winds to 55 knots diminishing
to gales to 40 knots after midnight. a chance of snow showers in
the evening. heavy freezing spray. waves subsiding to 3 to 6 feet
occasionally to 8 feet. 
.friday...north winds 15 to 25 knots becoming south gales to
35 knots. a chance of snow showers, then snow showers likely.
freezing spray. waves subsiding to 1 to 3 feet, then building to
6 to 9 feet occasionally to 11 feet. 
.saturday...west gales to 35 knots becoming northwest 20 to
30 knots. waves subsiding to 2 to 4 feet. 

note, wave height forecasts are for ice free areas.

$$