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000
FZUS63 KMQT 171343
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
943 AM EDT Wed Apr 17 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...This morning, Lake Superior is between a 30.4 inch
Hudson Bay High and a 29.5 inch low moving into SW WI. This low
will weaken to 29.7 inches as it lifts east across northern Lake
Michigan tonight before phasing with another 29.7 inch low
pressure over northern Ontario. This low moves into eastern James
Bay Friday night into Saturday, 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. Ridging over the lake builds to 30.1 inches
on Saturday and weakens to 30.0 inches Sunday.



LSZ162-172145-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
943 AM EDT Wed Apr 17 2024 /843 AM CDT Wed Apr 17 2024/

...GALE WARNING IN EFFECT UNTIL 5 PM EDT /4 PM CDT/ THIS
AFTERNOON...

.REST OF TODAY...Northeast gales to 35 knots becoming north 20 to
30 knots late. Rain showers. Waves 8 to 11 feet occasionally to
14 feet subsiding to 3 to 6 feet occasionally to 8 feet.
.TONIGHT...West winds 10 to 20 knots. A chance of rain showers
through midnight. Waves subsiding to 1 to 3 feet.
.THURSDAY...Southwest winds 5 to 15 knots increasing to 15 to
25 knots. A slight chance of rain showers by mid afternoon. Waves
subsiding to calm to 2 feet, then building to 3 to 5 feet
occasionally to 7 feet.
.THURSDAY NIGHT...West winds 15 to 25 knots. A slight chance of
rain showers. A slight chance of snow showers after midnight.
Waves subsiding to 2 to 4 feet, then building to 3 to 5 feet
occasionally to 7 feet.
.FRIDAY...West winds 20 to 30 knots. A chance of snow showers
through early afternoon. A chance of rain showers. Waves building
to 6 to 9 feet occasionally to 11 feet, then subsiding to 4 to
7 feet occasionally to 9 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots veering northwest after
midnight. Waves subsiding to 3 to 5 feet occasionally to 7 feet.
.SATURDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to 1 to 3 feet.
.SUNDAY...Southwest winds 15 to 25 knots becoming west 10 to
20 knots. Waves building to 2 to 4 feet, then subsiding to calm
to 2 feet.

$$

LSZ263-172145-
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-
943 AM EDT Wed Apr 17 2024

...GALE WARNING IN EFFECT UNTIL 5 PM EDT THIS AFTERNOON...

.REST OF TODAY...Northeast gales to 35 knots diminishing to 20 to
30 knots late. A chance of rain showers by late morning, then
rain showers and a slight chance of thunderstorms by mid
afternoon. Waves 10 to 14 feet occasionally to 18 feet subsiding
to 7 to 10 feet occasionally to 13 feet.
.TONIGHT...North winds 10 to 20 knots backing west after
midnight. A chance of rain showers. Waves subsiding to 2 to
4 feet.
.THURSDAY...Southwest winds 5 to 15 knots increasing to 10 to
20 knots in the afternoon, then veering west late. Waves
subsiding to 1 to 3 feet, then building to 3 to 5 feet
occasionally to 7 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots increasing to 15 to
25 knots after midnight. A slight chance of rain showers. Waves
building to 3 to 6 feet occasionally to 8 feet.
.FRIDAY...West winds 20 to 30 knots with a few gale force gusts to
35 knots possible. A chance of rain showers. Waves building to 6
to 10 feet occasionally to 13 feet.
.FRIDAY NIGHT...West winds 15 to 25 knots veering northwest after
midnight. Waves subsiding to 3 to 6 feet occasionally to 8 feet.
.SATURDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots. Waves subsiding to 2 to 4 feet.
.SUNDAY...West winds 15 to 25 knots becoming southwest 10 to
20 knots. Waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to 1 to 3 feet.

$$

LSZ264-172145-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
943 AM EDT Wed Apr 17 2024

...GALE WARNING IN EFFECT UNTIL 8 PM EDT THIS EVENING...

.REST OF TODAY...Southeast gales to 40 knots becoming east gales
to 35 knots late. A chance of rain showers by late morning, then
rain showers by mid afternoon. Waves 10 to 14 feet occasionally
to 18 feet subsiding to 7 to 10 feet occasionally to 13 feet.
.TONIGHT...East winds 15 to 25 knots becoming northwest 10 to
20 knots after midnight, then backing west late. Rain showers
likely through midnight, then a slight chance of rain showers
after midnight. Waves subsiding to 2 to 4 feet.
.THURSDAY...West winds 5 to 15 knots backing southwest in the
afternoon, then increasing to 10 to 20 knots late. Waves
subsiding to 1 to 3 feet, then building to 2 to 4 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots increasing to 15 to
25 knots after midnight. A slight chance of rain showers. Waves
building to 3 to 6 feet occasionally to 8 feet.
.FRIDAY...West winds 20 to 30 knots with a few gale force gusts to
35 knots possible. Waves building to 6 to 10 feet occasionally to
13 feet.
.FRIDAY NIGHT...West winds 15 to 25 knots becoming northwest
20 to 30 knots after midnight. Waves subsiding to 4 to 8 feet
occasionally to 10 feet.
.SATURDAY...Northwest winds 20 to 30 knots becoming west 10 to
20 knots. Waves subsiding to 2 to 4 feet, then building to 3 to
5 feet occasionally to 7 feet.
.SUNDAY...West winds 15 to 25 knots diminishing to 10 to
20 knots. Waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to 1 to 3 feet.

$$

LSZ265-172145-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
943 AM EDT Wed Apr 17 2024

...GALE WARNING IN EFFECT UNTIL 8 PM EDT THIS EVENING...

.REST OF TODAY...Southeast gales to 35 knots diminishing to 20 to
30 knots and backing east late. A chance of rain showers by late
morning, then rain showers by mid afternoon. Waves 8 to 11 feet
occasionally to 14 feet subsiding to 4 to 7 feet occasionally to 9
feet.
.TONIGHT...East winds 5 to 15 knots becoming west 15 to 25 knots
after midnight, then increasing to 20 to 30 knots late. A chance
of rain showers. Waves subsiding to 2 to 4 feet.
.THURSDAY...West winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then increasing to 10 to 20 knots
late. A slight chance of rain showers by mid afternoon. Waves
subsiding to calm to 2 feet.
.THURSDAY NIGHT...West winds 5 to 15 knots increasing to 10 to
20 knots after midnight. A slight chance of rain showers through
midnight. Waves building to 1 to 3 feet.
.FRIDAY...West winds 20 to 30 knots. A chance of rain showers.
Waves building to 3 to 6 feet occasionally to 8 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots. A chance of rain
showers, possibly mixed with snow. Waves 3 to 6 feet occasionally
to 8 feet.
.SATURDAY...Northwest winds 15 to 25 knots backing west. Waves
subsiding to calm to 2 feet, then building to 1 to 3 feet.
.SUNDAY...West winds 15 to 25 knots. Waves subsiding to calm to
2 feet.

$$

LSZ266-172145-
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-
943 AM EDT Wed Apr 17 2024

...GALE WARNING IN EFFECT UNTIL 8 PM EDT THIS EVENING...

.REST OF TODAY...Southeast gales to 40 knots. A chance of rain
showers by late morning, then rain showers by mid afternoon.
Waves 10 to 14 feet occasionally to 18 feet subsiding to 7 to
10 feet occasionally to 13 feet.
.TONIGHT...East winds 20 to 30 knots becoming west 15 to 25 knots
after midnight. A chance of rain showers. Waves subsiding to 2 to
4 feet, then building to 3 to 5 feet occasionally to 7 feet.
.THURSDAY...West winds 15 to 25 knots diminishing to 5 to
15 knots in the afternoon, then backing southwest late. A slight
chance of rain showers by mid afternoon. Waves subsiding to 1 to
3 feet.
.THURSDAY NIGHT...Southwest winds 5 to 15 knots becoming west
10 to 20 knots after midnight. A chance of rain showers. Waves
building to 3 to 5 feet occasionally to 7 feet.
.FRIDAY...West winds 20 to 30 knots. A chance of rain showers.
Waves building to 6 to 9 feet occasionally to 11 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots veering northwest after
midnight. A chance of rain showers through midnight. A chance of
snow showers. Waves subsiding to 5 to 8 feet occasionally to
10 feet, then building to 6 to 9 feet occasionally to 11 feet.
.SATURDAY...Northwest winds 20 to 30 knots becoming west 15 to
25 knots. Waves building to 7 to 10 feet occasionally to 13 feet,
then subsiding to 2 to 4 feet.
.SUNDAY...West winds 15 to 25 knots becoming southwest 10 to
20 knots. Waves building to 3 to 5 feet occasionally to 7 feet,
then subsiding to 1 to 3 feet.

$$

LSZ267-172145-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
943 AM EDT Wed Apr 17 2024

...GALE WARNING IN EFFECT UNTIL 8 PM EDT THIS EVENING...

.REST OF TODAY...Southeast gales to 40 knots. A chance of rain
showers. Waves 7 to 10 feet occasionally to 13 feet subsiding to
5 to 8 feet occasionally to 10 feet.
.TONIGHT...Southeast gales to 35 knots diminishing to 10 to
20 knots after midnight, then becoming west 15 to 25 knots late.
A chance of rain showers. Waves subsiding to calm to 2 feet, then
building to 2 to 4 feet.
.THURSDAY...West winds 15 to 25 knots diminishing to 5 to
15 knots. A slight chance of rain showers by mid afternoon. Waves
building to 3 to 6 feet occasionally to 8 feet, then subsiding to
1 to 3 feet.
.THURSDAY NIGHT...South winds 5 to 15 knots becoming west 10 to
20 knots after midnight. A chance of rain showers. Waves
subsiding to calm to 2 feet, then building to 1 to 3 feet.
.FRIDAY...West winds 15 to 25 knots increasing to 20 to 30 knots
by mid afternoon. A chance of rain showers. Waves building to
5 to 8 feet occasionally to 10 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots. A chance of rain
showers through midnight. A chance of snow showers. Waves building
to 7 to 10 feet occasionally to 13 feet.
.SATURDAY...Northwest winds 20 to 30 knots backing west. Waves
subsiding to 2 to 4 feet.
.SUNDAY...West winds 15 to 25 knots backing southwest. Waves
subsiding to 1 to 3 feet.

$$
LSZ261-172145-
MAFOR 1715/
Superior West...GALE WARNING IN EFFECT...12156 11846 11720 12620
11610 11510. Waves 7 to 11 feet subsiding to 6 to 9 feet this
afternoon. Waves 4 to 7 feet subsiding to 2 to 3 feet tonight.
Waves 2 to 3 feet Thursday morning.

Superior North Central...GALE WARNING IN EFFECT...11350 11356
11246 11236 11120 11720 11630 11620. Waves 10 to 14 feet this
afternoon. Waves 8 to 11 feet subsiding to 3 to 5 feet tonight.
Waves 2 to 4 feet Thursday morning.

Superior South Central...GALE WARNING IN EFFECT...11340 11346
11236 11210 11730 12640 11620. Waves 5 to 9 feet this afternoon.
Waves 4 to 7 feet subsiding to 3 to 5 feet tonight. Waves 3 to 5
feet subsiding to 2 to 4 feet Thursday morning.

Superior East...GALE WARNING IN EFFECT...12350 12356 11230 11610
11630 11620. Waves 7 to 11 feet this afternoon. Waves 6 to 9 feet
subsiding to 2 to 3 feet tonight. Waves 2 to 4 feet building to 3
to 5 feet Thursday morning.

$$

LC

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

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