Great Lakes Forecast
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FZUS63 KMQT 120750
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
350 AM EDT Tue Mar 12 2024

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 29.7 inch trough will move over Lake Superior today,
exiting east across Ontario and into Quebec tonight into
Wednesday. Behind the trough, 30.2 inch ridging builds southeast
from northern Manitoba, reaching the Upper Great Lakes by
Wednesday night. Thursday, Lake Superior will be between 30.3 inch
ridging over northern Ontario and a 29.8 inch low approaching
southern Lake Michigan. The ridge will remain overhead Friday,
but weaken Friday night to 30.0 inches while the low approaches
the Lower Great Lakes at 29.7 inches. Overnight Friday into
Saturday, a 29.4 inch Alberta Clipper low will approach Lake
Superior.

LSZ162-121600-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
350 AM EDT Tue Mar 12 2024 /250 AM CDT Tue Mar 12 2024/

.EARLY THIS MORNING...East winds 5 to 15 knots. Waves calm to
2 feet.
.TODAY...Northeast winds 5 to 15 knots backing west in the
afternoon, then increasing to 10 to 20 knots late. Waves calm to
2 feet.
.TONIGHT...Northwest winds 5 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...North winds 5 to 15 knots veering east late. Waves
calm to 2 feet.
.WEDNESDAY NIGHT...Northeast winds 5 to 15 knots increasing to
10 to 20 knots after midnight. Waves building to 1 to 3 feet.
.THURSDAY...Northeast winds 15 to 25 knots. Waves building to
3 to 5 feet occasionally to 7 feet.
.THURSDAY NIGHT...Northeast winds 10 to 20 knots. Waves subsiding
to 1 to 3 feet.
.FRIDAY...Northeast winds 5 to 15 knots becoming southwest 15 to
25 knots. A chance of rain showers. Waves subsiding to calm to
2 feet, then building to 2 to 4 feet.
.SATURDAY...West winds 20 to 30 knots veering northwest. A chance
of rain and snow showers. Waves subsiding to 1 to 3 feet, then
building to 2 to 4 feet.

$$

LSZ263-121600-
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-
350 AM EDT Tue Mar 12 2024

.EARLY THIS MORNING...Southeast winds less than 10 knots. Waves
calm to 2 feet.
.TODAY...East winds 5 to 15 knots veering west in the afternoon.
Waves calm to 2 feet.
.TONIGHT...Northwest winds 5 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...North winds 5 to 15 knots backing southwest late.
Waves calm to 2 feet.
.WEDNESDAY NIGHT...East winds 5 to 15 knots becoming northeast
10 to 20 knots after midnight. Waves building to 1 to 3 feet.
.THURSDAY...Northeast winds 10 to 20 knots. Waves building to
2 to 4 feet.
.THURSDAY NIGHT...Northeast winds 10 to 20 knots. Waves subsiding
to 1 to 3 feet, then building to 2 to 4 feet.
.FRIDAY...Northeast winds 5 to 15 knots becoming southwest 15 to
25 knots. A chance of rain and snow showers. Waves subsiding to
calm to 2 feet, then building to 2 to 4 feet.
.SATURDAY...West winds 15 to 25 knots veering northwest. A chance
of rain and snow showers. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 2 to 4 feet.

$$

LSZ264-121600-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
350 AM EDT Tue Mar 12 2024

.EARLY THIS MORNING...South winds less than 10 knots. Waves calm
to 2 feet.
.TODAY...Southeast winds 5 to 15 knots veering west late. Waves
calm to 2 feet.
.TONIGHT...Northwest winds 5 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...Northwest winds 5 to 15 knots backing west late.
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 5 to 15 knots. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.
.THURSDAY NIGHT...Northeast winds 10 to 20 knots. Waves building
to 2 to 4 feet.
.FRIDAY...Northeast winds 5 to 15 knots becoming southwest 10 to
20 knots. A chance of rain and snow showers. Waves subsiding to
calm to 2 feet, then building to 2 to 4 feet.
.SATURDAY...Southwest winds 15 to 25 knots veering northwest. A
chance of rain and snow showers. Waves building to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ265-121600-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
350 AM EDT Tue Mar 12 2024

.EARLY THIS MORNING...Southeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TODAY...Southeast winds 5 to 15 knots veering west late. Waves
calm to 2 feet.
.TONIGHT...Northwest winds 10 to 20 knots diminishing to 5 to
15 knots late. Waves calm to 2 feet.
.WEDNESDAY...Northwest winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then veering north late. Waves calm to
2 feet.
.WEDNESDAY NIGHT...North winds 5 to 15 knots becoming northeast
10 to 20 knots after midnight. Waves calm to 2 feet.
.THURSDAY...Northeast winds 10 to 20 knots. Waves building to
1 to 3 feet, then subsiding to calm to 2 feet.
.THURSDAY NIGHT...Northeast winds 10 to 20 knots. Waves building
to 2 to 4 feet.
.FRIDAY...Northeast winds 10 to 20 knots veering southwest. A
chance of rain and snow showers. Waves subsiding to calm to
2 feet.
.SATURDAY...Southwest winds 15 to 25 knots veering west. A chance
of rain and snow showers. Waves building to 1 to 3 feet, then
subsiding to calm to 2 feet.

$$

LSZ266-121600-
Lake Superior East of a line from Manitou Island to Marquette MI
and West of a line from Grand Marais MI to the US/Canadian Border
Beyond 5NM from shore-
350 AM EDT Tue Mar 12 2024

.EARLY THIS MORNING...South winds 5 to 15 knots. Waves calm to
2 feet.
.TODAY...Southeast winds 10 to 20 knots diminishing to 5 to
15 knots late. Waves calm to 2 feet.
.TONIGHT...Northwest winds 10 to 20 knots. Waves calm to 2 feet.
.WEDNESDAY...Northwest winds 10 to 20 knots. Waves building to
1 to 3 feet.
.WEDNESDAY NIGHT...North winds 10 to 20 knots veering northeast
after midnight. Waves subsiding to calm to 2 feet.
.THURSDAY...Northeast winds 10 to 20 knots. Waves building to
1 to 3 feet, then subsiding to calm to 2 feet.
.THURSDAY NIGHT...Northeast winds 10 to 20 knots increasing to
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.FRIDAY...Northeast winds 10 to 20 knots veering south. A chance
of rain and snow showers. Waves subsiding to calm to 2 feet, then
building to 1 to 3 feet.
.SATURDAY...Southwest winds 15 to 25 knots veering northwest. A
chance of rain showers. Waves building to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ267-121600-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
350 AM EDT Tue Mar 12 2024

.EARLY THIS MORNING...Southeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TODAY...Southeast winds 10 to 20 knots. Waves calm to 2 feet.
.TONIGHT...West winds 10 to 20 knots veering northwest after
midnight. Waves calm to 2 feet.
.WEDNESDAY...Northwest winds 10 to 20 knots. Waves building to
1 to 3 feet.
.WEDNESDAY NIGHT...Northwest winds 10 to 20 knots veering
northeast after midnight. Waves subsiding to calm to 2 feet.
.THURSDAY...Northeast winds 10 to 20 knots backing north by mid
afternoon. Waves building to 1 to 3 feet, then subsiding to calm
to 2 feet.
.THURSDAY NIGHT...Northeast winds 10 to 20 knots increasing to
15 to 25 knots after midnight. Waves building to 1 to 3 feet.
.FRIDAY...Northeast winds 10 to 20 knots veering southwest. Waves
subsiding to calm to 2 feet.
.SATURDAY...South winds 15 to 25 knots veering west. Rain showers
likely. A chance of rain showers. Waves building to 2 to 4 feet,
then subsiding to 1 to 3 feet.

$$

LSZ261-121600-
MAFOR 1209/
Superior West 11200 11100 11700 12610 11600 12700. Waves 2 feet
or less.

Superior North Central 11400 13300 11600 11700 12710. Waves 1 to
2 feet.

Superior South Central 14300 11700 11710 12700. Waves 1 foot or
less.

Superior East 11300 14310 11610 12710. Waves 2 feet or less.

$$

GS

Experimental modernized open lake forecast is available online at
weather.gov/mqt/glftable

Graphical marine forecasts are available online at:
weather.gov/greatlakes


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