fzus63 kmqt 152001
glfls 
expires:202509160800;;040361

open lake forecast for lake superior
national weather service marquette mi
401 pm edt mon sep 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 30.3 inch high over quebec this afternoon will maintain a 30.1 
inch ridge over lake superior through tonight. on tuesday the high 
will begin to weaken as it moves to and over new england. a 29.7 
inch low moving through far northern ontario into the hudson bay 
area tuesday night brings troughing of 30.0 inches back to lake 
superior tuesday night through wednesday, before a 30.3 inch high 
stretching from the canadian prairies to northern ontario brings 
30.1 inch ridging back over lake superior wednesday night into 
thursday morning. ridging is expected to strengthen to 30.3 inches 
on friday as the high digs through northern ontario towards the st. 
lawrence seaway. the ridge will weaken to 30.1 inches on saturday as 
the high pressure pushes away from the area, into the northeastern 
u.s.



lsz162-160800-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
401 pm edt mon sep 15 2025 /301 pm cdt mon sep 15 2025/

.late this afternoon...northeast winds 10 to 20 knots. a slight
chance of showers and thunderstorms. waves 1 to 3 feet. 
.tonight...northeast winds 5 to 15 knots veering east after
midnight, then veering south late. a slight chance of showers and
thunderstorms. waves subsiding to calm to 2 feet. 
.tuesday...south winds 5 to 15 knots. a slight chance of showers
through early afternoon. waves calm to 2 feet. 
.tuesday night...southwest winds 5 to 15 knots veering west late.
a slight chance of showers and thunderstorms after midnight.
waves calm to 2 feet. 
.wednesday...west winds 5 to 15 knots backing southwest by mid
afternoon. a slight chance of showers and thunderstorms. waves
calm to 2 feet. 
.wednesday night...north winds 5 to 15 knots veering northeast
after midnight. waves calm to 2 feet. 
.thursday...northeast winds 10 to 20 knots. waves building to
2 to 4 feet. 
.thursday night...northeast winds 10 to 20 knots increasing to
15 to 25 knots after midnight. waves subsiding to 1 to 3 feet,
then building to 2 to 4 feet. 
.friday...east winds 15 to 25 knots diminishing to 10 to
20 knots. waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to 1 to 3 feet. 
.saturday...east winds 10 to 20 knots diminishing to 5 to
15 knots. a chance of showers. waves subsiding to calm to 2 feet.

$$

fzus63 kmqt 152001
glfls 
expires:202509160800;;040362

open lake forecast for lake superior
national weather service marquette mi
401 pm edt mon sep 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 30.3 inch high over quebec this afternoon will maintain a 30.1 
inch ridge over lake superior through tonight. on tuesday the high 
will begin to weaken as it moves to and over new england. a 29.7 
inch low moving through far northern ontario into the hudson bay 
area tuesday night brings troughing of 30.0 inches back to lake 
superior tuesday night through wednesday, before a 30.3 inch high 
stretching from the canadian prairies to northern ontario brings 
30.1 inch ridging back over lake superior wednesday night into 
thursday morning. ridging is expected to strengthen to 30.3 inches 
on friday as the high digs through northern ontario towards the st. 
lawrence seaway. the ridge will weaken to 30.1 inches on saturday as 
the high pressure pushes away from the area, into the northeastern 
u.s.



lsz263-160800-
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-
401 pm edt mon sep 15 2025

.late this afternoon...east winds 5 to 15 knots. a slight chance
of showers. waves calm to 2 feet. 
.tonight...southeast winds 5 to 15 knots veering south after
midnight. patchy dense fog through midnight. a slight chance of
showers and thunderstorms. waves calm to 2 feet. 
.tuesday...south winds 5 to 15 knots veering southwest in the
afternoon, then backing south late. a slight chance of showers
through early afternoon. waves calm to 2 feet. 
.tuesday night...south winds 5 to 15 knots veering west late. a
slight chance of showers and thunderstorms after midnight. waves
calm to 2 feet. 
.wednesday...west winds 5 to 15 knots. a slight chance of showers
and thunderstorms. waves calm to 2 feet. 
.wednesday night...northeast winds 5 to 15 knots increasing to
10 to 20 knots after midnight. waves calm to 2 feet. 
.thursday...northeast winds 10 to 20 knots. waves building to
2 to 4 feet. 
.thursday night...northeast winds 10 to 20 knots veering east
after midnight. waves subsiding to 1 to 3 feet, then building to
2 to 4 feet. 
.friday...east winds 15 to 25 knots diminishing to 10 to
20 knots. waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to calm to 2 feet. 
.saturday...east winds 5 to 15 knots veering southeast. a chance
of showers. waves building to 1 to 3 feet, then subsiding to calm
to 2 feet. 

$$