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000
FZUS63 KMQT 230740
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
340 AM EDT Tue Apr 23 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...29.5 inch low pressure will track across eastern Lake
Superior today, weakening to 29.6 inches by the afternoon.
Meanwhile a 30.3 inch high pressure shifts into northern Manitoba
and into northern Ontario Tuesday evening. This high strengthens
to 30.4 inches and quickly shifts south across Lake Superior
Tuesday night and Wednesday. Ridging spreads east of the area
Thursday ahead of a low pressure system that deepens to 29.2
inches over the Central Plains Friday. Saturday morning the low
fills to 29.4 as spins over the Upper Great Lakes.

LSZ162-231545-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
340 AM EDT Tue Apr 23 2024 /240 AM CDT Tue Apr 23 2024/

.EARLY THIS MORNING...Southwest winds 5 to 15 knots. Waves calm
to 2 feet.
.TODAY...West winds 15 to 25 knots becoming northeast 20 to
30 knots in the afternoon, then veering east late. A chance of
rain showers, possibly mixed with snow. Waves building to 4 to
8 feet occasionally to 10 feet.
.TONIGHT...Northeast winds 10 to 20 knots. Waves subsiding to
3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...East winds 10 to 20 knots. Waves subsiding to calm
to 2 feet, then building to 1 to 3 feet.
.WEDNESDAY NIGHT...East winds 5 to 15 knots. Waves subsiding to
calm to 2 feet.
.THURSDAY...East winds 10 to 20 knots. Waves building to 2 to
4 feet.
.THURSDAY NIGHT...East winds 10 to 20 knots veering southeast
after midnight. Waves subsiding to 1 to 3 feet.
.FRIDAY...East winds 15 to 25 knots increasing to 20 to 30 knots.
A chance of rain showers. Rain showers. Waves building to 2 to
4 feet, then subsiding to 1 to 3 feet.
.SATURDAY...Northeast winds 15 to 25 knots increasing to 20 to
30 knots. Rain showers. A chance of rain showers. Waves building
to 3 to 5 feet occasionally to 7 feet.

$$

LSZ263-231545-
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-
340 AM EDT Tue Apr 23 2024

...GALE WARNING IN EFFECT FROM 8 AM THIS MORNING TO 2 PM EDT THIS
AFTERNOON...

.EARLY THIS MORNING...West winds 5 to 15 knots. Waves 1 to
3 feet.
.TODAY...North winds 20 to 30 knots becoming northeast gales to
35 knots in the afternoon, then diminishing to 20 to 30 knots
late. A chance of snow and rain showers. Waves building to 7 to
10 feet occasionally to 13 feet, then subsiding to 5 to 8 feet
occasionally to 10 feet.
.TONIGHT...Northeast winds 15 to 25 knots diminishing to 10 to
20 knots late. Waves subsiding to 3 to 6 feet occasionally to
8 feet, then building to 4 to 7 feet occasionally to 9 feet.
.WEDNESDAY...East winds 5 to 15 knots. Waves subsiding to calm to
2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots becoming east 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 15 to 25 knots veering south
after midnight. Waves building to 3 to 5 feet occasionally to
7 feet.
.FRIDAY...Southeast winds 20 to 30 knots backing east. A chance
of rain showers, then rain showers. Waves building to 3 to 6 feet
occasionally to 8 feet.
.SATURDAY...North winds 15 to 25 knots veering northeast. Rain
showers. A chance of rain showers. Waves subsiding to 2 to
4 feet, then building to 3 to 6 feet occasionally to 8 feet.

$$

LSZ264-231545-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
340 AM EDT Tue Apr 23 2024

...GALE WARNING IN EFFECT FROM 8 AM THIS MORNING TO 2 PM EDT THIS
AFTERNOON...

.EARLY THIS MORNING...West winds 5 to 15 knots. Waves 1 to 3 feet
building to 2 to 4 feet.
.TODAY...North winds 20 to 30 knots increasing to gales to
35 knots in the afternoon. A chance of rain showers through early
afternoon. A chance of snow showers. Waves building to 9 to
12 feet occasionally to 15 feet, then subsiding to 7 to 10 feet
occasionally to 13 feet.
.TONIGHT...Northeast winds 15 to 25 knots diminishing to 10 to
20 knots late. Waves subsiding to 5 to 8 feet occasionally to
10 feet, then building to 6 to 9 feet occasionally to 11 feet.
.WEDNESDAY...Northeast winds 5 to 15 knots veering southeast
late. Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...South winds 5 to 15 knots. Waves calm to
2 feet.
.THURSDAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots by mid afternoon. Waves building to 1 to 3 feet.
.THURSDAY NIGHT...Southeast winds 20 to 30 knots veering south
after midnight. Waves building to 3 to 6 feet occasionally to
8 feet.
.FRIDAY...Southeast winds 20 to 30 knots. A chance of rain
showers, then rain showers. Waves building to 4 to 8 feet
occasionally to 10 feet.
.SATURDAY...Southeast winds 15 to 25 knots backing north. Rain
showers. A chance of rain showers. Waves subsiding to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ265-231545-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
340 AM EDT Tue Apr 23 2024

...GALE WARNING IN EFFECT FROM 8 AM THIS MORNING TO 2 PM EDT THIS
AFTERNOON...

.EARLY THIS MORNING...Southwest winds 10 to 20 knots. Waves calm
to 2 feet.
.TODAY...West winds 10 to 20 knots becoming north gales to
35 knots in the afternoon. A slight chance of rain showers. A
chance of snow showers by mid afternoon. Waves building to 9 to
12 feet occasionally to 15 feet.
.TONIGHT...Northeast winds 20 to 30 knots diminishing to 15 to
25 knots late. Waves subsiding to 4 to 7 feet occasionally to
9 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots becoming east 5 to
15 knots in the afternoon. Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 15 to 25 knots veering south
after midnight. Waves building to 2 to 4 feet.
.FRIDAY...Southeast winds 20 to 30 knots. A chance of rain
showers, then rain showers. Waves building to 3 to 6 feet
occasionally to 8 feet.
.SATURDAY...South winds 20 to 30 knots backing north. Rain
showers. A chance of rain showers. Waves subsiding to 1 to
3 feet, then building to 3 to 5 feet occasionally to 7 feet.

$$

LSZ266-231545-
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-
340 AM EDT Tue Apr 23 2024

...GALE WARNING IN EFFECT FROM 8 AM THIS MORNING TO 2 PM EDT THIS
AFTERNOON...

.EARLY THIS MORNING...Southwest winds 10 to 20 knots. A slight
chance of rain showers. Waves 2 to 4 feet.
.TODAY...West winds 20 to 30 knots becoming north gales to
35 knots in the afternoon. A slight chance of rain showers. A
chance of snow showers by mid afternoon. Waves building to 10 to
14 feet occasionally to 18 feet, then subsiding to 9 to 12 feet
occasionally to 15 feet.
.TONIGHT...Northeast gales to 35 knots diminishing to 15 to
25 knots. Waves subsiding to 4 to 7 feet occasionally to 9 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then becoming north less than 10 knots
late. Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...South winds 5 to 15 knots. Waves calm to
2 feet.
.THURSDAY...South winds 5 to 15 knots becoming southeast 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 20 to 30 knots. Waves building to
3 to 6 feet occasionally to 8 feet.
.FRIDAY...Southeast winds 20 to 30 knots increasing to gales to
35 knots. Rain showers. Waves building to 4 to 8 feet
occasionally to 10 feet.
.SATURDAY...South winds 20 to 30 knots backing north. Rain
showers. A chance of rain showers. Waves subsiding to 2 to
4 feet, then building to 3 to 6 feet occasionally to 8 feet.

$$

LSZ267-231545-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
340 AM EDT Tue Apr 23 2024

...GALE WARNING IN EFFECT FROM 2 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT...

.EARLY THIS MORNING...South winds 15 to 25 knots. A slight chance
of rain showers. Waves 2 to 4 feet.
.TODAY...Southwest winds 10 to 20 knots veering west in the
afternoon, then becoming north gales to 35 knots late. A slight
chance of rain showers through early afternoon. A slight chance
of snow showers by mid afternoon. Waves subsiding to 1 to 3 feet,
then building to 8 to 11 feet occasionally to 14 feet.
.TONIGHT...Northeast gales to 35 knots diminishing to 20 to
30 knots after midnight. Freezing spray after midnight. Waves
subsiding to 3 to 6 feet occasionally to 8 feet.
.WEDNESDAY...Northeast winds 10 to 20 knots backing north in the
afternoon, then becoming northwest 5 to 15 knots late. Waves
subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...Northwest winds 5 to 15 knots backing south
after midnight. Waves calm to 2 feet.
.THURSDAY...South winds 10 to 20 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 15 to 25 knots backing southeast
after midnight. Waves building to 3 to 6 feet occasionally to
8 feet.
.FRIDAY...Southeast winds 20 to 30 knots increasing to gales to
35 knots. Rain showers. Waves subsiding to 3 to 6 feet
occasionally to 8 feet.
.SATURDAY...South winds 20 to 30 knots becoming southwest 15 to
25 knots. Rain showers. Waves subsiding to 2 to 4 feet.

$$

LSZ261-231545-
MAFOR 2309/
Superior West...GALE WARNING IN EFFECT...11510 11720 12140 19150
13130 11120. A chance of snow showers this afternoon. Waves 1 to 3
feet building to 5 to 8 feet today. Waves 4 to 7 feet subsiding
to 3 to 6 feet tonight.

Superior North Central...GALE WARNING IN EFFECT...11610 11740
12850 11150 12140 11130. A chance of rain showers this morning. A
chance of snow showers this afternoon. Waves 2 to 4 feet building
to 8 to 12 feet today. Waves 7 to 10 feet subsiding to 4 to 7
feet tonight.

Superior South Central...GALE WARNING IN EFFECT...11620 11610
11830 12850 12140 11130. A chance of snow showers this afternoon.
Waves 1 to 3 feet building to 10 to 13 feet today, subsiding to 6
to 9 feet tonight.

Superior East...GALE WARNING IN EFFECT...11530 11510 11620 11840
12150 11140 11141. Waves 2 to 4 feet building to 5 to 8 feet
today. Waves 7 to 11 feet subsiding to 6 to 9 feet tonight.

$$

GS

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

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