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000
FZUS63 KMQT 192002
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
402 PM EDT Fri Apr 19 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... Low pressure is centered over western James Bay at
29.6 inches this afternoon. This low pressure slowly moves into
northern Quebec through Saturday morning, deepening to 29.3
inches. Meanwhile, a 30.4 inch high pressure ridge builds
southeast into the Northern Plains extending weak 30.0 inch
ridging across western Lake Superior. The ridge builds to 30.1
inches on Saturday, creating a tight southwest to northeast
pressure gradient over the lake Saturday morning. The gradient
begins to slack on Sunday as 30.3 inch high pressure slides into
the southern Plains, and a weak 29.9 inch trough extending from
Quebec dips over the east half of Lake Superior. A brief period of
30.1 inch high pressure meanders south out of the Canadian
Prairie Sunday night into Monday before broad 29.6 inch low
pressure begins moving eastward into the Great Lakes on Tuesday.
This low centers over Lake Superior Tuesday morning at 29.6 inches
then weakens to 29.8 inches over the lower Great Lakes through
the day. 30.3 inch high pressure over northern Ontario follows in
its wake Wednesday.

LSZ162-200415-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
402 PM EDT Fri Apr 19 2024 /302 PM CDT Fri Apr 19 2024/

.LATE THIS AFTERNOON...West winds 20 to 30 knots. A chance of
rain and snow showers. Waves 4 to 7 feet occasionally to 9 feet
subsiding to 3 to 6 feet occasionally to 8 feet.
.TONIGHT...West winds 15 to 25 knots increasing to 20 to 30 knots
after midnight, then veering northwest late. A slight chance of
rain and snow showers through midnight. Waves subsiding to 3 to
5 feet occasionally to 7 feet.
.SATURDAY...Northwest winds 15 to 25 knots backing west in the
afternoon. Waves subsiding to 2 to 4 feet.
.SATURDAY NIGHT...West winds 10 to 20 knots. Waves subsiding to
1 to 3 feet, then building to 2 to 4 feet.
.SUNDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots
by mid afternoon. Waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to 2 to 4 feet.
.SUNDAY NIGHT...Northeast winds 5 to 15 knots veering east after
midnight. Waves subsiding to calm to 2 feet.
.MONDAY...East winds 10 to 20 knots increasing to 15 to 25 knots
by mid afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...East winds 15 to 25 knots becoming northeast
20 to 30 knots after midnight. Rain showers. Snow showers likely
after midnight. Waves building to 3 to 5 feet occasionally to
7 feet.
.TUESDAY...Northeast winds 20 to 30 knots diminishing to 15 to
25 knots. A chance of rain showers, possibly mixed with snow.
Waves building to 3 to 6 feet occasionally to 8 feet, then
subsiding to 1 to 3 feet.
.WEDNESDAY...East winds 10 to 20 knots. Waves subsiding to calm
to 2 feet.

$$

LSZ263-200415-
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-
402 PM EDT Fri Apr 19 2024

...GALE WARNING IN EFFECT UNTIL 11 PM EDT THIS EVENING...

.LATE THIS AFTERNOON...West winds 20 to 30 knots with a few gale
force gusts to 35 knots possible. Sprinkles. Waves 6 to 10 feet
occasionally to 13 feet.
.TONIGHT...West winds 15 to 25 knots with a few gale force gusts
to 35 knots possible veering northwest late. A slight chance of
rain showers through midnight. A slight chance of snow showers.
Waves subsiding to 4 to 7 feet occasionally to 9 feet.
.SATURDAY...Northwest winds 15 to 25 knots backing west in the
afternoon. Waves subsiding to 3 to 6 feet occasionally to 8 feet.
.SATURDAY NIGHT...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 3 to 6 feet occasionally to 8 feet.
.SUNDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots
by mid afternoon. Waves subsiding to 2 to 4 feet.
.SUNDAY NIGHT...East winds 5 to 15 knots veering southeast after
midnight. Waves subsiding to calm to 2 feet.
.MONDAY...Southeast winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...East winds 15 to 25 knots. Rain showers likely.
Waves building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...Northeast winds 15 to 25 knots. A chance of snow
showers. A chance of rain showers. Waves building to 3 to 6 feet
occasionally to 8 feet, then subsiding to 2 to 4 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots becoming south 5 to
15 knots. Waves subsiding to calm to 2 feet.

$$

LSZ264-200415-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
402 PM EDT Fri Apr 19 2024

...GALE WARNING IN EFFECT UNTIL 11 PM EDT THIS EVENING...

.LATE THIS AFTERNOON...West gales to 35 knots. Sprinkles. Waves
7 to 10 feet occasionally to 13 feet.
.TONIGHT...West winds 20 to 30 knots with a few gale force gusts
to 35 knots possible diminishing to 15 to 25 knots after
midnight, then veering northwest late. A slight chance of rain
showers. A slight chance of snow showers after midnight. Waves
subsiding to 4 to 7 feet occasionally to 9 feet.
.SATURDAY...Northwest winds 15 to 25 knots backing west in the
afternoon, then increasing to 20 to 30 knots late. Waves
subsiding to 3 to 6 feet occasionally to 8 feet, then building to
4 to 7 feet occasionally to 9 feet.
.SATURDAY NIGHT...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 3 to 6 feet occasionally to 8 feet.
.SUNDAY...Northwest winds 15 to 25 knots becoming north 10 to
20 knots by mid afternoon. Waves subsiding to 2 to 4 feet.
.SUNDAY NIGHT...East winds 5 to 15 knots veering southeast after
midnight. Waves subsiding to calm to 2 feet.
.MONDAY...Southeast winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY NIGHT...Southeast winds 10 to 20 knots becoming east
15 to 25 knots after midnight. A chance of rain showers through
midnight, then rain showers likely after midnight. Waves building
to 2 to 4 feet.
.TUESDAY...North winds 15 to 25 knots. A chance of rain showers.
Waves building to 3 to 6 feet occasionally to 8 feet, then
subsiding to 2 to 4 feet.
.WEDNESDAY...North winds 10 to 20 knots becoming south 5 to
15 knots. Waves subsiding to calm to 2 feet.

$$

LSZ265-200415-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
402 PM EDT Fri Apr 19 2024

...GALE WARNING IN EFFECT UNTIL 2 AM EDT SATURDAY...

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

$$

LSZ266-200415-
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-
402 PM EDT Fri Apr 19 2024

...GALE WARNING IN EFFECT UNTIL 2 AM EDT SATURDAY...

.LATE THIS AFTERNOON...West gales to 35 knots. Waves 7 to 10 feet
occasionally to 13 feet.
.TONIGHT...West winds 20 to 30 knots with a few gale
force gusts to 35 knots possible veering northwest late. A
slight chance of rain and snow showers. Waves subsiding to 5 to
8 feet occasionally to 10 feet.
.SATURDAY...Northwest winds 20 to 30 knots backing west late. A
slight chance of snow showers through early afternoon. Waves
building to 6 to 9 feet occasionally to 11 feet, then subsiding
to 4 to 7 feet occasionally to 9 feet.
.SATURDAY NIGHT...West winds 15 to 25 knots. Waves subsiding to
3 to 6 feet occasionally to 8 feet, then building to 4 to 7 feet
occasionally to 9 feet.
.SUNDAY...Northwest winds 15 to 25 knots becoming north 10 to
20 knots by mid afternoon. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.SUNDAY NIGHT...North winds 5 to 15 knots veering south after
midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...South winds 10 to 20 knots backing southeast by mid
afternoon. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...Southeast winds 15 to 25 knots. A chance of rain
showers through midnight, then rain showers likely after
midnight. Waves building to 2 to 4 feet.
.TUESDAY...North winds 20 to 30 knots. A chance of rain showers.
Waves building to 3 to 6 feet occasionally to 8 feet.
.WEDNESDAY...North winds 15 to 25 knots becoming southwest 10 to
20 knots. Waves subsiding to calm to 2 feet.

$$

LSZ267-200415-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
402 PM EDT Fri Apr 19 2024

...GALE WARNING IN EFFECT UNTIL 2 AM EDT SATURDAY...

.LATE THIS AFTERNOON...West gales to 35 knots. Waves 5 to 9 feet
occasionally to 11 feet.
.TONIGHT...West gales to 35 knots. A slight chance of rain and
snow showers. Waves subsiding to 5 to 8 feet occasionally to
10 feet.
.SATURDAY...Northwest winds 20 to 30 knots increasing to gales to
35 knots in the afternoon, then backing west late. A slight
chance of snow showers through early afternoon. Waves building to
5 to 9 feet occasionally to 11 feet.
.SATURDAY NIGHT...West winds 20 to 30 knots diminishing to 15 to
25 knots after midnight. Waves subsiding to 3 to 6 feet
occasionally to 8 feet, then building to 4 to 7 feet occasionally
to 9 feet.
.SUNDAY...West winds 20 to 30 knots veering northwest by mid
afternoon. Waves building to 4 to 8 feet occasionally to 10 feet.
.SUNDAY NIGHT...Northwest winds 15 to 25 knots becoming southeast
10 to 20 knots after midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...South winds 10 to 20 knots backing southeast by mid
afternoon. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...Southeast winds 15 to 25 knots. Rain showers
likely after midnight. Waves building to 1 to 3 feet.
.TUESDAY...North winds 20 to 30 knots. A chance of rain showers.
Waves building 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.

$$

LSZ261-200415-
MAFOR 1921/
Superior West...GALE WARNING IN EFFECT...11640 12630 13730 12630.
Waves 5 to 8 feet subsiding to 3 to 6 feet tonight subsiding to 2
to 4 feet Saturday.

Superior North Central...GALE WARNING IN EFFECT...11650 12640
11740 13730 11640. Waves 7 to 11 feet subsiding to 5 to 8 feet
tonight then subsiding to 3 to 6 feet Saturday.

Superior South Central...GALE WARNING IN EFFECT...14640 11740
11730 11740 11640. Waves 4 to 7 feet.

Superior East...GALE WARNING IN EFFECT...14640 14740. Waves 6 to
9 feet.

$$

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