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000
FZUS63 KMQT 202014
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
414 PM EDT Sat Apr 20 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 30.4 inch high pressure over the north-central
Plains extends 30.1 inch ridging across Lake Superior on Sunday
before shifting over the Lower Great Lakes on Monday. Meanwhile,
29.7 inch troughing over Alberta on Sunday tracks east-southeast
across the Canadian Prairies on Monday. By Monday night, a 29.5
inch low pressure is expected to track near or across Lake
Superior before shifting east of the Great Lakes on Tuesday. A
30.3 inch high pressure over northern Ontario quickly shifts south
across Lake Superior Tuesday night and Wednesday. Ridging shifts
east of the area Wednesday night and Thursday as a 29.4 inch low
pressure develops on the north-central Plains.

LSZ162-210415-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
414 PM EDT Sat Apr 20 2024 /314 PM CDT Sat Apr 20 2024/

.LATE THIS AFTERNOON...West winds 15 to 25 knots. Waves 2 to
4 feet.
.TONIGHT...West winds 10 to 20 knots. Waves subsiding to calm to
2 feet, then building to 2 to 4 feet.
.SUNDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots
in the afternoon, then backing southwest late. Waves subsiding to
calm to 2 feet.
.SUNDAY NIGHT...Southwest winds 5 to 15 knots backing south after
midnight, then veering southwest late. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots becoming south 10 to
20 knots by mid afternoon. A slight chance of rain showers by mid
afternoon. Waves building to 1 to 3 feet.
.MONDAY NIGHT...Southwest winds 10 to 20 knots veering west after
midnight. Rain showers through midnight, then a chance of rain
showers after midnight. Waves 1 to 3 feet.
.TUESDAY...Northeast winds 20 to 30 knots. Rain showers, possibly
mixed with snow through early afternoon, then a chance of rain
and snow showers by mid afternoon. Waves building to 3 to 6 feet
occasionally to 8 feet.
.TUESDAY NIGHT...Northeast winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to 2 to 4 feet.
.WEDNESDAY...East winds 10 to 20 knots. Waves subsiding to calm
to 2 feet.
.THURSDAY...East winds 10 to 20 knots increasing to 15 to
25 knots. A chance of rain showers. Waves building to 1 to
3 feet.

$$

LSZ263-210415-
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-
414 PM EDT Sat Apr 20 2024

.LATE THIS AFTERNOON...West winds 20 to 30 knots. Waves 3 to
6 feet occasionally to 8 feet.
.TONIGHT...West winds 15 to 25 knots diminishing to 10 to
20 knots after midnight, then increasing to 15 to 25 knots late.
Waves subsiding to 2 to 4 feet.
.SUNDAY...West winds 10 to 20 knots diminishing to 5 to 15 knots
in the afternoon, then backing southwest late. Waves subsiding to
calm to 2 feet.
.SUNDAY NIGHT...Southwest winds 5 to 15 knots backing south after
midnight. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south by mid
afternoon. Waves building to 1 to 3 feet.
.MONDAY NIGHT...Southwest winds 10 to 20 knots increasing to
20 to 30 knots after midnight. Rain showers. Waves building to
3 to 6 feet occasionally to 8 feet.
.TUESDAY...North gales to 35 knots veering northeast by mid
afternoon. A chance of rain and snow showers. Waves building to
5 to 9 feet occasionally to 11 feet.
.TUESDAY NIGHT...Northeast winds 20 to 30 knots with a few gale
force gusts to 35 knots possible early then diminishing to 15 to
25 knots after midnight. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots becoming south 5 to
15 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots. Waves building to 1 to 3 feet.

$$

LSZ264-210415-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
414 PM EDT Sat Apr 20 2024

.LATE THIS AFTERNOON...West winds 20 to 30 knots. Waves 3 to
6 feet occasionally to 8 feet building to 4 to 7 feet
occasionally to 9 feet.
.TONIGHT...West winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Waves subsiding to 2 to 4 feet.
.SUNDAY...Northwest winds 10 to 20 knots veering north in the
afternoon, then becoming southeast 5 to 15 knots late. Waves
subsiding to 1 to 3 feet.
.SUNDAY NIGHT...Southeast winds 5 to 15 knots veering south after
midnight. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south by mid
afternoon. Waves building to 1 to 3 feet.
.MONDAY NIGHT...South winds 10 to 20 knots becoming north 20 to
30 knots after midnight. Rain showers. Waves building to 3 to
6 feet occasionally to 8 feet.
.TUESDAY...North gales to 35 knots. A chance of rain and snow
showers. Waves building to 6 to 10 feet occasionally to 13 feet.
.TUESDAY NIGHT...North winds 20 to 30 knots with a few gale force
gusts to 35 knots possible early then becoming northeast 15 to 25
knots after midnight. Waves subsiding to 3 to 5 feet occasionally
to 7 feet.
.WEDNESDAY...North winds 10 to 20 knots becoming southwest 5 to
15 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots. Waves building to 2 to
4 feet.

$$

LSZ265-210415-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
414 PM EDT Sat Apr 20 2024

.LATE THIS AFTERNOON...West winds 15 to 25 knots. Waves 3 to
5 feet occasionally to 7 feet subsiding to 2 to 4 feet.
.TONIGHT...West winds 15 to 25 knots. Waves subsiding to 1 to
3 feet.
.SUNDAY...Northwest winds 15 to 25 knots veering north in the
afternoon, then diminishing to 10 to 20 knots late. Waves 1 to
3 feet.
.SUNDAY NIGHT...Southeast winds 10 to 20 knots diminishing to
5 to 15 knots after midnight, then veering south late. Waves
subsiding to calm to 2 feet.
.MONDAY...South winds 5 to 15 knots increasing to 10 to 20 knots
by mid afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 10 to 20 knots veering southwest
after midnight. Rain showers. Waves building to 1 to 3 feet.
.TUESDAY...North winds 20 to 30 knots increasing to gales to
35 knots by mid afternoon. A chance of rain and snow showers.
Waves building to 6 to 10 feet occasionally to 13 feet.
.TUESDAY NIGHT...North winds 20 to 30 knots with a few gale force
gusts to 35 knots possible early. Waves subsiding to 3 to 6 feet
occasionally to 8 feet.
.WEDNESDAY...North winds 15 to 25 knots becoming south 10 to
20 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots veering south. Waves
building to 1 to 3 feet.

$$

LSZ266-210415-
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-
414 PM EDT Sat Apr 20 2024

.LATE THIS AFTERNOON...West winds 15 to 25 knots. Waves 4 to
8 feet occasionally to 10 feet.
.TONIGHT...West winds 15 to 25 knots increasing to 20 to 30 knots
late. Waves subsiding to 3 to 5 feet occasionally to 7 feet.
.SUNDAY...Northwest winds 20 to 30 knots diminishing to 15 to
25 knots in the afternoon, then becoming north 10 to 20 knots
late. Waves building to 3 to 6 feet occasionally to 8 feet.
.SUNDAY NIGHT...East winds 5 to 15 knots veering south after
midnight, then increasing to 10 to 20 knots late. Waves subsiding
to calm to 2 feet, then building to 1 to 3 feet.
.MONDAY...South winds 10 to 20 knots. Waves subsiding to calm to
2 feet.
.MONDAY NIGHT...South winds 10 to 20 knots increasing to 20 to
30 knots after midnight. A chance of rain showers through
midnight, then rain showers after midnight. Waves building to
3 to 5 feet occasionally to 7 feet.
.TUESDAY...North gales to 35 knots. Rain showers likely through
early afternoon. A chance of snow showers. A chance of rain
showers by mid afternoon. Waves building to 7 to 10 feet
occasionally to 13 feet.
.TUESDAY NIGHT...Northeast winds 20 to 30 knots with a few gale
force gusts to 35 knots possible early then diminishing to 20 to
30 knots after midnight. Waves subsiding to 3 to 6 feet
occasionally to 8 feet.
.WEDNESDAY...North winds 15 to 25 knots becoming northwest 10 to
20 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...South winds 10 to 20 knots. Waves building to 2 to
4 feet.

$$

LSZ267-210415-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
414 PM EDT Sat Apr 20 2024

.LATE THIS AFTERNOON...West winds 20 to 30 knots. Waves 5 to
8 feet occasionally to 10 feet.
.TONIGHT...West winds 20 to 30 knots diminishing to 15 to
25 knots after midnight. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.SUNDAY...West winds 20 to 30 knots veering northwest in the
afternoon, then diminishing to 15 to 25 knots late. Waves
building to 4 to 7 feet occasionally to 9 feet.
.SUNDAY NIGHT...Northwest winds 10 to 20 knots diminishing to
5 to 15 knots after midnight, then becoming south 10 to 20 knots
late. Waves subsiding to calm to 2 feet.
.MONDAY...South winds 10 to 20 knots. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.
.MONDAY NIGHT...South winds 15 to 25 knots. A chance of rain
showers through midnight, then rain showers after midnight. Waves
building to 3 to 5 feet occasionally to 7 feet, then subsiding to
2 to 4 feet.
.TUESDAY...West winds 20 to 30 knots becoming north gales to
35 knots by mid afternoon. Rain showers likely through early
afternoon, then a chance of rain and snow showers by mid
afternoon. Waves building to 5 to 8 feet occasionally to 10 feet.
.TUESDAY NIGHT...North winds 20 to 30 knots with a few gale force
gusts to 35 knots possible early then diminishing to 20 to 30
knots after midnight. Waves subsiding to 3 to 6 feet occasionally
to 8 feet.
.WEDNESDAY...North winds 20 to 30 knots becoming northwest 10 to
20 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...South winds 10 to 20 knots. Waves building to 1 to
3 feet.

$$

LSZ261-210415-
MAFOR 2021/
Superior West 11530 11620 11610 11620 12630 11620 11610. Waves 3
to 5 feet subsiding to 2 to 4 feet tonight. Waves 2 to 4 feet
subsiding to 1 to 3 feet Sunday.

Superior North Central 11640 11630 11620 12630 11730 11830 11820.
Waves 3 to 6 feet building to 4 to 7 feet, then subsiding to 3 to
6 feet tonight. Waves 2 to 4 feet Sunday.

Superior South Central 15630 11720 11820. Waves 3 to 6 feet
subsiding to 2 to 4 feet tonight. Waves 2 to 4 feet Sunday.

Superior East 11640 14630 13730. Waves 5 to 8 feet tonight. Waves
3 to 6 feet Sunday.

$$

EK

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

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