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National Weather Service Marine Forecast FZUS63 KMQT
FZUS63 KMQT 311329
GLFLS
Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
929 AM EDT Mon Mar 31 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 29.4 inch surface low moves farther into southern
Quebec this morning as a 30.4 inch high shifts into northern
Manitoba. The high continues through northern Ontario Tuesday and
enables ridging of 30.3 inches over the Upper Great Lakes. As this
high builds to 30.6 inches over Quebec Wednesday morning, a 29.1
inch low lifts from the Central Plains Wednesday through the Upper
Great Lakes Wednesday night while weakening to 29.3 inches. The
low exits northeastern Lake Superior Thursday morning, and 30.4
inch ridging returns across Lake Superior Friday morning. The
ridging continues through the day into Saturday.
LSZ162-312130
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM
929 AM EDT Mon Mar 31 2025 /829 AM CDT Mon Mar 31 2025/
GALE WATCH IN EFFECT FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY EVENING
REST OF TODAY
North winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then backing southwest late. Waves
3 to 5 feet occasionally to 7 feet subsiding to calm to 2 feet.
TONIGHT
North winds 5 to 15 knots veering east late. Waves
calm to 2 feet.
TUESDAY
East winds 10 to 20 knots increasing to 15 to 25 knots
late. A slight chance of snow by mid afternoon. Waves building to
3 to 5 feet occasionally to 7 feet.
TUESDAY NIGHT
East winds 15 to 25 knots increasing to gales to
35 knots after midnight. A chance of snow through midnight, then
snow likely after midnight. Waves building to 6 to 9 feet
occasionally to 11 feet.
WEDNESDAY
East gales to 35 knots. Snow. Rain by mid afternoon.
Waves building to 10 to 14 feet occasionally to 18 feet.
WEDNESDAY NIGHT
East winds 20 to 30 knots becoming northwest
15 to 25 knots after midnight. Rain and snow likely through
midnight, then a chance of snow, possibly mixed with rain after
midnight. Waves subsiding to 3 to 6 feet occasionally to 8 feet.
THURSDAY
West winds 10 to 20 knots diminishing to 5 to
15 knots. Waves subsiding to calm to 2 feet.
FRIDAY
West winds 5 to 15 knots becoming northwest 10 to
20 knots. Waves calm to 2 feet.
LSZ263-312130
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
929 AM EDT Mon Mar 31 2025
GALE WATCH IN EFFECT FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY EVENING
REST OF TODAY
North winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then becoming southwest 5 to 15 knots
late. Waves 3 to 6 feet occasionally to 8 feet subsiding to calm
to 2 feet.
TONIGHT
West winds 5 to 15 knots veering north after midnight,
then veering northeast late. Waves calm to 2 feet.
TUESDAY
East winds 5 to 15 knots increasing to 15 to 25 knots.
Waves building to 3 to 5 feet occasionally to 7 feet.
TUESDAY NIGHT
East winds 15 to 25 knots increasing to gales to
35 knots after midnight. A chance of snow. Waves building to 6 to
9 feet occasionally to 11 feet.
WEDNESDAY
East gales to 45 knots. Snow. Rain by mid afternoon.
Waves building to 15 to 20 feet occasionally to 25 feet.
WEDNESDAY NIGHT
East gales to 40 knots becoming west 15 to
25 knots after midnight. Rain likely through midnight. Snow
likely. A chance of rain after midnight. Waves subsiding to 5 to
8 feet occasionally to 10 feet.
THURSDAY
West winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to calm to 2 feet.
FRIDAY
West winds 5 to 15 knots backing southwest. Waves calm
to 2 feet.
LSZ264-312130
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border
929 AM EDT Mon Mar 31 2025
GALE WATCH IN EFFECT FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY EVENING
REST OF TODAY
North winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon, then backing northwest late. Freezing
spray by late morning. Waves 4 to 7 feet occasionally to 9 feet
subsiding to 2 to 4 feet.
TONIGHT
North winds 5 to 15 knots veering northeast after
midnight, then backing north late. Waves subsiding to calm to
2 feet.
TUESDAY
Northeast winds 5 to 15 knots veering east in the
afternoon, then becoming southeast 10 to 20 knots late. Waves
building to 1 to 3 feet.
TUESDAY NIGHT
Southeast winds 15 to 25 knots increasing to
gales to 35 knots after midnight. A slight chance of snow after
midnight. Waves building to 7 to 10 feet occasionally to 13 feet.
WEDNESDAY
East gales to 45 knots. Snow likely through early
afternoon, then snow by mid afternoon. Waves building to 15 to
20 feet occasionally to 25 feet.
WEDNESDAY NIGHT
East gales to 45 knots becoming northwest
15 to 25 knots after midnight. Rain, possibly mixed with snow.
Waves subsiding to 5 to 8 feet occasionally to 10 feet.
THURSDAY
Northwest winds 20 to 30 knots diminishing to 10 to
20 knots. Waves subsiding to 1 to 3 feet.
FRIDAY
West winds 5 to 15 knots backing southwest. Waves
subsiding to calm to 2 feet.
LSZ265-312130
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore
929 AM EDT Mon Mar 31 2025
GALE WATCH IN EFFECT FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY EVENING
REST OF TODAY
North winds 20 to 30 knots diminishing to 15 to
25 knots in the afternoon, then backing northwest late. Freezing
spray by late morning. Waves 6 to 9 feet occasionally to 11 feet
subsiding to 3 to 6 feet occasionally to 8 feet.
TONIGHT
Northwest winds 10 to 20 knots diminishing to 5 to
15 knots after midnight, then backing west late. Waves subsiding
to calm to 2 feet.
TUESDAY
South winds 5 to 15 knots backing southeast in the
afternoon, then increasing to 15 to 25 knots late. Waves building
to 1 to 3 feet.
TUESDAY NIGHT
Southeast winds 20 to 30 knots. A slight chance
of snow after midnight. Waves building to 6 to 9 feet
occasionally to 11 feet.
WEDNESDAY
East gales to 40 knots veering southeast by mid
afternoon. Snow. Rain by mid afternoon. Waves building to 11 to
15 feet occasionally to 19 feet, then subsiding to 10 to 14 feet
occasionally to 18 feet.
WEDNESDAY NIGHT
Southeast winds 20 to 30 knots veering
southwest after midnight. A chance of rain, possibly mixed with
snow. Waves subsiding to 2 to 4 feet.
THURSDAY
West winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to calm to 2 feet.
FRIDAY
West winds 10 to 20 knots backing southwest. Waves calm
to 2 feet.
LSZ266-312130
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
929 AM EDT Mon Mar 31 2025
GALE WATCH IN EFFECT FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY EVENING
REST OF TODAY
North winds 20 to 30 knots backing northwest
late. Freezing spray by late morning. Waves 6 to 9 feet
occasionally to 11 feet subsiding to 4 to 7 feet occasionally to
9 feet.
TONIGHT
North winds 15 to 25 knots diminishing to 10 to
20 knots after midnight, then becoming west 5 to 15 knots late.
Waves subsiding to 1 to 3 feet.
TUESDAY
South winds 5 to 15 knots becoming southeast 10 to
20 knots in the afternoon, then increasing to 15 to 25 knots
late. Waves subsiding to calm to 2 feet, then building to 1 to
3 feet.
TUESDAY NIGHT
Southeast winds 15 to 25 knots increasing to
gales to 35 knots after midnight. A slight chance of snow after
midnight. Waves building to 7 to 10 feet occasionally to 13 feet.
WEDNESDAY
East gales to 45 knots. Snow. Rain by mid afternoon.
Waves building to 12 to 17 feet occasionally to 21 feet, then
subsiding to 11 to 15 feet occasionally to 19 feet.
WEDNESDAY NIGHT
Southeast gales to 35 knots becoming southwest
15 to 25 knots after midnight. Rain likely through midnight. Snow
likely. A chance of rain after midnight. Waves subsiding to 4 to
7 feet occasionally to 9 feet.
THURSDAY
West winds 15 to 25 knots becoming northwest 10 to
20 knots. Waves subsiding to 3 to 6 feet occasionally to 8 feet,
then building to 4 to 7 feet occasionally to 9 feet.
FRIDAY
Northwest winds 10 to 20 knots backing southwest. Waves
subsiding to calm to 2 feet.
LSZ267-312130
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border
929 AM EDT Mon Mar 31 2025
GALE WATCH IN EFFECT FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY EVENING
REST OF TODAY
North winds 20 to 30 knots diminishing to 15 to
25 knots in the afternoon, then becoming northwest 20 to 30 knots
late. Freezing spray by late morning. Waves 4 to 7 feet
occasionally to 9 feet subsiding to 3 to 5 feet occasionally to
7 feet, then building to 3 to 6 feet occasionally to 8 feet.
TONIGHT
North winds 20 to 30 knots diminishing to 10 to
20 knots after midnight, then becoming northeast 5 to 15 knots
late. Waves building to 4 to 7 feet occasionally to 9 feet, then
subsiding to 1 to 3 feet.
TUESDAY
Southeast winds 10 to 20 knots. Waves subsiding to
calm to 2 feet.
TUESDAY NIGHT
Southeast winds 15 to 25 knots increasing to
gales to 35 knots after midnight. Waves building to 6 to 9 feet
occasionally to 11 feet.
WEDNESDAY
Southeast gales to 45 knots. Snow likely. Rain by
mid afternoon. Waves building to 9 to 12 feet occasionally to
15 feet.
WEDNESDAY NIGHT
Southeast gales to 35 knots becoming south
15 to 25 knots after midnight. Rain likely through midnight, then
a chance of rain after midnight. Waves subsiding to 3 to 6 feet
occasionally to 8 feet.
THURSDAY
West winds 20 to 30 knots becoming northwest 10 to
20 knots. A chance of rain, possibly mixed with snow. Waves
building to 5 to 8 feet occasionally to 10 feet, then subsiding
to 2 to 4 feet.
FRIDAY
Northwest winds 10 to 20 knots backing southwest. Waves
subsiding to calm to 2 feet.
LSZ261-312130
MAFOR 3115/ Superior West 11820 11610 11510 11710 11810 11110 12210. Waves 3 to 5 feet subsiding to 1 to 3 feet this afternoon through Tuesday morning.
Superior North Central 11831 12720 11820 12100 11810 11110. Waves 3 to 6 feet this afternoon. Waves 2 to 4 feet subsiding to 1 to 3 feet tonight through Tuesday morning.
Superior South Central 11831 13730 11810 11700 11600 11500. Waves 5 to 8 feet this afternoon. Waves 3 to 6 feet subsiding to 1 to 3 feet tonight through Tuesday morning.
Superior East 11831 12730 11840 11830 11110 11200 11310. Waves 3 to 6 feet this afternoon, subsiding to 2 to 4 feet tonight. Waves 1 to 3 feet Tuesday morning.
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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