Great Lakes Forecast
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000
FZUS63 KMQT 220135
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
935 PM EDT Thu Mar 21 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... Ridging of 30.4 inches across the Great Lakes tonight
begins to slowly break down as a weak 30.2 inch inverted trough
moves across Lake Superior on Friday. 30.4 inch ridging builds
back into the High Plains and Lake Superior on Saturday. A deep
low pressure near 29.2 inches ejects out of Rockies on Sunday.
This low begins to weaken to 29.5 inches as it moves towards the
western Great Lakes on Monday, reaching central Wisconsin by
Tuesday morning.


LSZ162-220945-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
935 PM EDT Thu Mar 21 2024 /835 PM CDT Thu Mar 21 2024/

.REST OF TONIGHT...East winds 5 to 15 knots veering southeast
late. A slight chance of snow showers after midnight. Waves calm
to 2 feet.
.FRIDAY...Northeast winds 5 to 15 knots backing north in the
afternoon, then becoming northwest 10 to 20 knots late. A slight
chance of snow showers through early afternoon. Waves calm to
2 feet.
.FRIDAY NIGHT...Northwest winds 15 to 25 knots veering north
after midnight, then diminishing to 10 to 20 knots late. Waves
building to 3 to 5 feet occasionally to 7 feet, then subsiding to
1 to 3 feet.
.SATURDAY...North winds 5 to 15 knots backing southwest by mid
afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...South winds 5 to 15 knots backing southeast
after midnight. Waves calm to 2 feet.
.SUNDAY...East winds 10 to 20 knots increasing to 15 to 25 knots
by mid afternoon. A chance of snow showers through early
afternoon, then snow showers likely by mid afternoon. Waves
building to 3 to 5 feet occasionally to 7 feet.
.SUNDAY NIGHT...East winds 20 to 30 knots. Snow showers. Waves
building to 4 to 7 feet occasionally to 9 feet, then subsiding to
3 to 6 feet occasionally to 8 feet.
.MONDAY...East gales to 35 knots backing northeast. Snow showers.
Rain showers. Waves building to 8 to 11 feet occasionally to
14 feet, then subsiding to 4 to 7 feet occasionally to 9 feet.
.TUESDAY...North winds 20 to 30 knots backing west. Rain and snow
showers likely, then a chance of snow showers. Waves subsiding to
2 to 4 feet.

$$

LSZ263-220945-
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-
935 PM EDT Thu Mar 21 2024

.REST OF TONIGHT...Southwest winds 5 to 15 knots backing east
after midnight, then veering south late. A slight chance of snow
showers after midnight. Waves calm to 2 feet.
.FRIDAY...North winds 5 to 15 knots backing northwest late. A
chance of snow showers through early afternoon. Waves calm to
2 feet.
.FRIDAY NIGHT...Northwest winds 10 to 20 knots veering north
after midnight. Waves building to 3 to 6 feet occasionally to
8 feet, then subsiding to 2 to 4 feet.
.SATURDAY...North winds 5 to 15 knots backing southwest by mid
afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...Southwest winds 5 to 15 knots backing southeast
after midnight. Waves calm to 2 feet.
.SUNDAY...Southeast winds 5 to 15 knots becoming east 15 to
25 knots by mid afternoon. A chance of snow showers. Waves
building to 2 to 4 feet.
.SUNDAY NIGHT...East winds 15 to 25 knots increasing to 20 to
30 knots after midnight. Snow showers. Waves building to 3 to
6 feet occasionally to 8 feet.
.MONDAY...East gales to 35 knots. Snow showers. Rain showers.
Waves building to 8 to 11 feet occasionally to 14 feet, then
subsiding to 5 to 8 feet occasionally to 10 feet.
.TUESDAY...West winds 15 to 25 knots increasing to 20 to
30 knots. Rain and snow showers likely, then a chance of snow
showers, possibly mixed with rain. Waves subsiding to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ264-220945-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
935 PM EDT Thu Mar 21 2024

.REST OF TONIGHT...West winds 5 to 15 knots backing south late. A
slight chance of snow showers after midnight. Waves calm to
2 feet.
.FRIDAY...West winds 5 to 15 knots veering northwest in the
afternoon. A chance of snow showers. Waves building to 1 to
3 feet.
.FRIDAY NIGHT...North winds 10 to 20 knots increasing to 15 to
25 knots after midnight, then diminishing to 10 to 20 knots late.
Waves building to 3 to 6 feet occasionally to 8 feet.
.SATURDAY...North winds 5 to 15 knots backing west by mid
afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...Southwest winds 5 to 15 knots backing south
after midnight. Waves calm to 2 feet.
.SUNDAY...Southeast winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. A chance of snow showers. Waves
building to 1 to 3 feet.
.SUNDAY NIGHT...East winds 10 to 20 knots increasing to 20 to
30 knots after midnight. Snow showers. Waves building to 4 to
7 feet occasionally to 9 feet.
.MONDAY...East gales to 35 knots. Snow showers. Rain showers
likely. Waves building to 8 to 11 feet occasionally to 14 feet,
then subsiding to 6 to 9 feet occasionally to 11 feet.
.TUESDAY...Southeast winds 20 to 30 knots veering west. Rain and
snow showers likely, then a chance of snow showers, possibly
mixed with rain. Waves subsiding to 3 to 6 feet occasionally to
8 feet.

$$

LSZ265-220945-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
935 PM EDT Thu Mar 21 2024

.REST OF TONIGHT...North winds 5 to 15 knots veering south after
midnight. A chance of snow showers after midnight. Waves calm to
2 feet.
.FRIDAY...Southwest winds 5 to 15 knots veering north in the
afternoon, then increasing to 10 to 20 knots late. Snow showers
likely through early afternoon, then a chance of snow showers by
mid afternoon. Waves building to 1 to 3 feet.
.FRIDAY NIGHT...Northwest winds 15 to 25 knots veering north
after midnight. A slight chance of snow showers. Waves building
to 3 to 6 feet occasionally to 8 feet.
.SATURDAY...North winds 10 to 20 knots becoming northwest 5 to
15 knots by mid afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...South winds 5 to 15 knots. Waves calm to
2 feet.
.SUNDAY...South winds 10 to 20 knots becoming southeast 15 to
25 knots by mid afternoon. A chance of snow showers. Waves
building to 1 to 3 feet.
.SUNDAY NIGHT...Southeast winds 15 to 25 knots becoming east
20 to 30 knots after midnight. Snow showers. Waves building to
3 to 6 feet occasionally to 8 feet.
.MONDAY...East gales to 35 knots veering southeast. Snow showers.
Rain showers. Waves building to 6 to 9 feet occasionally to
11 feet, then subsiding to 4 to 7 feet occasionally to 9 feet.
.TUESDAY...South winds 20 to 30 knots veering west. Rain showers
likely. A chance of snow showers. A chance of rain showers. Waves
subsiding to 2 to 4 feet.

$$

LSZ266-220945-
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-
935 PM EDT Thu Mar 21 2024

.REST OF TONIGHT...North winds 5 to 15 knots veering south after
midnight. A chance of snow showers after midnight. Waves calm to
2 feet.
.FRIDAY...South winds 10 to 20 knots veering west in the
afternoon, then veering northwest late. Snow showers likely
through early afternoon, then a chance of snow showers by mid
afternoon. Waves building to 1 to 3 feet.
.FRIDAY NIGHT...Northwest winds 15 to 25 knots veering north
after midnight. A slight chance of snow showers. Waves building
to 4 to 7 feet occasionally to 9 feet.
.SATURDAY...North winds 10 to 20 knots becoming northwest 5 to
15 knots by mid afternoon. A slight chance of snow showers
through early afternoon. Waves subsiding to 1 to 3 feet.
.SATURDAY NIGHT...West winds 5 to 15 knots backing south after
midnight. Waves subsiding to calm to 2 feet.
.SUNDAY...South winds 10 to 20 knots becoming southeast 15 to
25 knots by mid afternoon. A chance of snow showers by mid
afternoon. Waves building to 1 to 3 feet.
.SUNDAY NIGHT...Southeast winds 15 to 25 knots increasing to
20 to 30 knots after midnight. Snow showers. Waves building to
4 to 7 feet occasionally to 9 feet.
.MONDAY...East gales to 35 knots veering southeast. Snow showers
likely, then rain showers. Waves building to 6 to 10 feet
occasionally to 13 feet.
.TUESDAY...South winds 20 to 30 knots veering west. Rain showers
likely. A chance of snow showers. A chance of rain showers. Waves
subsiding to 3 to 6 feet occasionally to 8 feet.

$$

LSZ267-220945-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
935 PM EDT Thu Mar 21 2024

.REST OF TONIGHT...Northwest winds 10 to 20 knots diminishing to
5 to 15 knots after midnight, then backing south late. A chance
of snow showers after midnight. Waves calm to 2 feet.
.FRIDAY...South winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then backing southeast late. Snow
showers likely through early afternoon, then a chance of snow
showers by mid afternoon. Waves building to 1 to 3 feet, then
subsiding to calm to 2 feet.
.FRIDAY NIGHT...Northwest winds 10 to 20 knots becoming north
15 to 25 knots after midnight. A chance of snow showers. Freezing
spray after midnight. Waves building to 3 to 6 feet occasionally
to 8 feet.
.SATURDAY...North winds 10 to 20 knots backing northwest by mid
afternoon. A slight chance of snow showers through early
afternoon. Waves subsiding to 1 to 3 feet.
.SATURDAY NIGHT...Northwest winds 5 to 15 knots backing south
after midnight. Waves subsiding to calm to 2 feet.
.SUNDAY...South winds 10 to 20 knots backing southeast by mid
afternoon. Waves building to 1 to 3 feet.
.SUNDAY NIGHT...Southeast winds 15 to 25 knots increasing to
20 to 30 knots after midnight. Snow showers. Waves building to
3 to 6 feet occasionally to 8 feet.
.MONDAY...East gales to 35 knots veering southeast. Snow showers
likely. Rain showers. Waves building to 4 to 8 feet occasionally
to 10 feet.
.TUESDAY...Southeast gales to 35 knots becoming west 20 to
30 knots. Rain showers, possibly mixed with snow. Waves subsiding
to 2 to 4 feet, then building to 3 to 6 feet occasionally to
8 feet.

$$
LSZ261-220945-
MAFOR 2203/
Superior West 13200 11100 11800 11710 11720 11730. Waves 1 foot
or less overnight and Friday building to 2 to 4 feet Friday
evening.

Superior North Central 11600 12400 11500 13710 11720. A chance of
snow showers Friday. Waves 1 to 4 feet.

Superior South Central 11100 12400 11517 11617 11710 11820 11720.
Waves 2 feet or less overnight and Friday building to waves 2 to
4 feet Friday evening.

Superior East 11710 11600 11410 11327 11427 11520 11620 11720.
Waves 1 to 3 feet overnight and Friday building to 2 to 4 feet
Friday evening.

$$

WFO MQT

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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