fzus63 kmqt 240202
glfls 
expires:202604240800;;883814

open lake forecast for lake superior
national weather service marquette mi
1001 pm edt thu apr 23 2026

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...

ridging continues over james bay tonight while a 29.2 inch low sits 
over southern manitoba. between now and friday evening, the james 
bay high persists while the canadian low swings farther north into 
manitoba, sending troughing of around 29.6 inches across lake 
superior. late friday and into saturday, the parent low weakens 
considerably as remnant troughing moves south and 30.0 inch ridging 
builds over lake superior by late saturday. this ridge builds to 
30.1 inches by late sunday and persists into early monday. 
meanwhile, a 29.3 inch colorado low develops, moving towards the 
upper midwest by early monday, causing pressure over lake superior 
to fall rapidly toward 29.7 inches by mid-monday. lake superior 
pressure continues to fall as this 29.3 inch low reaches mn/wi by 
late monday and lake superior by early tuesday, causing pressure 
over the lake to remain low near 29.3 throughout tuesday. this low 
lifts north into ontario wednesday morning, and lake superior 
pressures increase to 29.8 inches by wednesday midday.



lsz162-240800-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
1001 pm edt thu apr 23 2026 /901 pm cdt thu apr 23 2026/

.rest of tonight...east winds 10 to 20 knots backing northeast
late. rain showers likely and a chance of thunderstorms. waves
3 to 6 feet occasionally to 8 feet. 
.friday...west winds 10 to 20 knots diminishing to 5 to 15 knots
late. a chance of rain showers. waves subsiding to 2 to 4 feet. 
.friday night...west winds 5 to 15 knots veering north after
midnight, then backing northwest late. waves subsiding to calm to
2 feet. 
.saturday...northwest winds 5 to 15 knots veering east by mid
afternoon. waves calm to 2 feet. 
.saturday night...east winds 5 to 15 knots backing northeast
after midnight. waves calm to 2 feet. 
.sunday...northeast winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. waves calm to 2 feet. 
.sunday night...east winds 10 to 20 knots becoming northeast
15 to 25 knots after midnight. waves building to 3 to 5 feet
occasionally to 7 feet. 
.monday...east winds 20 to 30 knots backing northeast. rain
showers likely. waves building to 7 to 10 feet occasionally to
13 feet, then subsiding to 5 to 8 feet occasionally to 10 feet. 
.tuesday...west winds 20 to 30 knots diminishing to 15 to
25 knots. a chance of rain showers. waves subsiding to 1 to
3 feet. 

$$

fzus63 kmqt 240202
glfls 
expires:202604240800;;883815

open lake forecast for lake superior
national weather service marquette mi
1001 pm edt thu apr 23 2026

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...

ridging continues over james bay tonight while a 29.2 inch low sits 
over southern manitoba. between now and friday evening, the james 
bay high persists while the canadian low swings farther north into 
manitoba, sending troughing of around 29.6 inches across lake 
superior. late friday and into saturday, the parent low weakens 
considerably as remnant troughing moves south and 30.0 inch ridging 
builds over lake superior by late saturday. this ridge builds to 
30.1 inches by late sunday and persists into early monday. 
meanwhile, a 29.3 inch colorado low develops, moving towards the 
upper midwest by early monday, causing pressure over lake superior 
to fall rapidly toward 29.7 inches by mid-monday. lake superior 
pressure continues to fall as this 29.3 inch low reaches mn/wi by 
late monday and lake superior by early tuesday, causing pressure 
over the lake to remain low near 29.3 throughout tuesday. this low 
lifts north into ontario wednesday morning, and lake superior 
pressures increase to 29.8 inches by wednesday midday.



lsz263-240800-
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 edt thu apr 23 2026

.rest of tonight...southeast winds 20 to 30 knots. rain showers
and a chance of thunderstorms. waves 6 to 9 feet occasionally to
11 feet building to 7 to 10 feet occasionally to 13 feet. 
.friday...west winds 20 to 30 knots diminishing to 10 to
20 knots. rain showers and a slight chance of thunderstorms
through early afternoon, then a chance of rain showers by mid
afternoon. waves subsiding to 3 to 6 feet occasionally to 8 feet.
.friday night...northwest winds 10 to 20 knots becoming north
5 to 15 knots after midnight, then backing northwest late. waves
subsiding to calm to 2 feet. 
.saturday...northwest winds 5 to 15 knots backing south by mid
afternoon. waves calm to 2 feet. 
.saturday night...east winds 5 to 15 knots diminishing to less
than 10 knots after midnight. waves calm to 2 feet. 
.sunday...east winds 5 to 15 knots backing northeast by mid
afternoon. waves calm to 2 feet. 
.sunday night...east winds 5 to 15 knots increasing to 10 to
20 knots after midnight. waves building to 1 to 3 feet. 
.monday...east winds 20 to 30 knots increasing to gales to
35 knots. a chance of rain showers, then rain showers likely.
waves building to 10 to 14 feet occasionally to 18 feet, then
subsiding to 8 to 11 feet occasionally to 14 feet. 
.tuesday...west gales to 35 knots diminishing to 15 to 25 knots.
a chance of rain showers. waves subsiding to 4 to 8 feet
occasionally to 10 feet. 

$$