fzus63 kmqt 230301
glfls 
expires:202512230900;;058135

open lake forecast for lake superior
national weather service marquette mi
1001 pm est mon dec 22 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 29.8 inch low will press east near thunder bay late tonight into 
thursday. afterwards, a 30.4 inch high pressure moves over lake 
superior from the canadian prairies tuesday night with weak 
troughing of 30.0 inches moving over the lake late wednesday as the 
high shifts east. 30.3 inch ridging builds back in for thursday as a 
30.5 inch high transits ontario. low pressure of at least 29.6 
inches moves through the lower midwest friday. a deepening low will 
then lift into the upper great lakes saturday night into sunday.



lsz162-230900-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
1001 pm est mon dec 22 2025 /901 pm cst mon dec 22 2025/

.rest of tonight...southeast winds 5 to 15 knots veering south by
midnight, then becoming southwest 10 to 20 knots late. a slight
chance of rain and snow after midnight. waves calm to 2 feet
building to 1 to 3 feet. 
.tuesday...west winds 15 to 25 knots increasing to 20 to 30 knots
by late morning, then becoming northwest 15 to 25 knots by mid
afternoon. waves building to 3 to 6 feet occasionally to 8 feet,
then subsiding to 2 to 4 feet. 
.tuesday night...north winds 5 to 15 knots veering northeast by
midnight, then veering southeast late. a slight chance of snow
showers after midnight. waves subsiding to calm to 2 feet. 
.wednesday...south winds 5 to 15 knots veering southwest in the
afternoon. a slight chance of snow showers in the morning. waves
calm to 2 feet. 
.wednesday night...north winds 5 to 15 knots becoming northeast
10 to 20 knots after midnight. waves building to 1 to 3 feet. 
.thursday...east winds 15 to 25 knots. a chance of snow showers
in the afternoon. waves building to 3 to 6 feet occasionally to
8 feet. 
.thursday night...east winds 15 to 25 knots. snow showers likely.
rain showers likely after midnight. waves 3 to 6 feet
occasionally to 8 feet. 
.friday...east winds 10 to 20 knots becoming south 5 to 15 knots.
a chance of snow showers, possibly mixed with rain. waves
subsiding to 1 to 3 feet. 
.saturday...southwest winds 10 to 20 knots becoming northwest
gales to 35 knots. a chance of rain and snow showers. waves
building to 3 to 6 feet occasionally to 8 feet. 

note, wave height forecasts are for ice free areas.

$$

fzus63 kmqt 230301
glfls 
expires:202512230900;;058136

open lake forecast for lake superior
national weather service marquette mi
1001 pm est mon dec 22 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 29.8 inch low will press east near thunder bay late tonight into 
thursday. afterwards, a 30.4 inch high pressure moves over lake 
superior from the canadian prairies tuesday night with weak 
troughing of 30.0 inches moving over the lake late wednesday as the 
high shifts east. 30.3 inch ridging builds back in for thursday as a 
30.5 inch high transits ontario. low pressure of at least 29.6 
inches moves through the lower midwest friday. a deepening low will 
then lift into the upper great lakes saturday night into sunday.



lsz263-230900-
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-
1001 pm est mon dec 22 2025

.rest of tonight...southeast winds 5 to 15 knots veering south by
midnight, then becoming southwest 10 to 20 knots late. a slight
chance of rain and snow after midnight. waves calm to 2 feet
building to 1 to 3 feet. 
.tuesday...west winds 20 to 30 knots veering northwest by mid
afternoon. waves building to 5 to 8 feet occasionally to 10 feet,
then subsiding to 3 to 6 feet occasionally to 8 feet. 
.tuesday night...north winds 10 to 20 knots diminishing to 5 to
15 knots by midnight, then veering southeast late. waves
subsiding to calm to 2 feet. 
.wednesday...south winds 5 to 15 knots veering southwest in the
afternoon. a slight chance of snow showers in the morning. waves
calm to 2 feet. 
.wednesday night...northwest winds 5 to 15 knots becoming north
10 to 20 knots after midnight. waves building to 2 to 4 feet. 
.thursday...northeast winds 10 to 20 knots becoming east 20 to
30 knots in the afternoon. waves building to 3 to 6 feet
occasionally to 8 feet. 
.thursday night...east winds 20 to 30 knots veering southeast
after midnight. snow showers likely. waves building to 6 to
9 feet occasionally to 11 feet. 
.friday...southeast winds 15 to 25 knots becoming south 10 to
20 knots. a chance of snow showers. waves subsiding to 2 to
4 feet. 
.saturday...south winds 15 to 25 knots becoming northwest gales
to 40 knots. a chance of rain and snow showers. freezing spray.
waves building to 8 to 11 feet occasionally to 14 feet. 

note, wave height forecasts are for ice free areas.

$$