fzus63 kmqt 200201
glfls 
expires:202608200800;;022387

open lake forecast for lake superior
national weather service marquette mi
1000 pm edt wed aug 19 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...

30.0 inch high pressure remains over the upper great lakes tonight 
before expanding into the rest of the great lakes at 30.1 inches on 
thursday. a weakening shortwave low of 29.8 inches moves towards 
western lake superior on thursday, eventually bringing 29.9 inch 
troughing back over the lake thursday night. friday into this 
weekend, a low pressure of around 29.8 inches transits across 
northern ontario, reinforcing 29.9 inch troughing over lake superior 
friday into saturday morning. this is quickly followed by 30.1 inch 
ridging for the latter part of the weekend into early next week via 
a 30.2 inch parent high from canada that drops down into the ohio 
river valley by late monday.




lsz162-200800-
lake superior west of a line from saxon harbor wi to grand
portage mn beyond 5nm-
1001 pm edt wed aug 19 2026 /901 pm cdt wed aug 19 2026/

.rest of tonight...south winds 5 to 15 knots becoming northeast
less than 10 knots after midnight, then veering east late. a
slight chance of showers after midnight. waves calm to 2 feet. 
.thursday...east winds less than 10 knots increasing to 5 to
15 knots in the afternoon. a chance of showers and thunderstorms.
waves calm to 2 feet. 
.thursday night...east winds 10 to 20 knots becoming northeast
5 to 15 knots after midnight, then backing north late. a chance
of showers and a slight chance of thunderstorms through midnight.
waves calm to 2 feet. 
.friday...north winds 5 to 15 knots backing southwest by mid
afternoon. waves calm to 2 feet. 
.friday night...west winds 5 to 15 knots increasing to 10 to
20 knots after midnight. a slight chance of showers after
midnight. waves calm to 2 feet. 
.saturday...northwest winds 10 to 20 knots becoming west 5 to
15 knots by mid afternoon. waves calm to 2 feet. 
.saturday night...northwest winds 10 to 20 knots becoming north
5 to 15 knots after midnight. waves calm to 2 feet. 
.sunday...north winds 5 to 15 knots veering northeast. waves calm
to 2 feet. 
.monday...east winds 5 to 15 knots. a chance of showers. waves
calm to 2 feet. 

$$