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000
FZUS63 KMQT 190751
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
351 AM 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...A broad area of low pressure is centered over
northern Ontario at 29.7 inches this morning. This area of low
pressure slowly moves into James Bay 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 29.7 inch
low pressure begins moving eastward into the Great Lakes on
Tuesday.

LSZ162-191600-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
351 AM EDT Fri Apr 19 2024 /251 AM CDT Fri Apr 19 2024/

.EARLY THIS MORNING...West winds 20 to 30 knots. Waves 3 to
6 feet occasionally to 8 feet.
.TODAY...West winds 20 to 30 knots. Sprinkles. Waves building to
4 to 8 feet occasionally to 10 feet.
.TONIGHT...West winds 20 to 30 knots veering northwest late.
Waves subsiding to 3 to 5 feet occasionally to 7 feet.
.SATURDAY...Northwest winds 20 to 30 knots becoming west 15 to
25 knots in the afternoon. Waves subsiding to 2 to 4 feet.
.SATURDAY NIGHT...West winds 15 to 25 knots. Waves subsiding to
1 to 3 feet.
.SUNDAY...West winds 15 to 25 knots. Waves building to 3 to
5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet.
.SUNDAY NIGHT...East winds 10 to 20 knots. Waves subsiding to
calm to 2 feet.
.MONDAY...East winds 10 to 20 knots increasing to 20 to 30 knots.
Rain showers likely. 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.

$$

LSZ263-191600-
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-
351 AM EDT Fri Apr 19 2024

...GALE WARNING IN EFFECT FROM 11 AM EDT THIS MORNING THROUGH
THIS EVENING...

.EARLY THIS MORNING...West winds 15 to 25 knots. Waves 3 to
6 feet occasionally to 8 feet building to 4 to 7 feet
occasionally to 9 feet.
.TODAY...West winds 20 to 30 knots increasing to gales to
35 knots in the afternoon. Flurries through early afternoon.
Sprinkles. Waves building to 7 to 11 feet occasionally to
14 feet.
.TONIGHT...West winds 20 to 30 knots becoming northwest 15 to
25 knots late. 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.
.SATURDAY NIGHT...West winds 15 to 25 knots increasing to 20 to
30 knots after midnight. Waves subsiding to 3 to 6 feet
occasionally to 8 feet.
.SUNDAY...West winds 20 to 30 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 becoming east 15 to
25 knots. A chance of rain showers. 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 and snow showers. Waves building to
3 to 6 feet occasionally to 8 feet, then subsiding to 2 to
4 feet.

$$

LSZ264-191600-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
351 AM EDT Fri Apr 19 2024

...GALE WARNING IN EFFECT FROM 11 AM EDT THIS MORNING THROUGH
THIS EVENING...

.EARLY THIS MORNING...West winds 15 to 25 knots. Waves 3 to
6 feet occasionally to 8 feet building to 4 to 7 feet
occasionally to 9 feet.
.TODAY...West winds 20 to 30 knots increasing to gales to
35 knots in the afternoon. A chance of snow showers through early
afternoon. Sprinkles. Waves building to 8 to 11 feet occasionally
to 14 feet.
.TONIGHT...West winds 20 to 30 knots becoming northwest 15 to
25 knots late. A slight chance of rain showers through 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 20 to 30 knots. Waves subsiding to
3 to 6 feet occasionally to 8 feet.
.SUNDAY...West winds 20 to 30 knots becoming north 10 to 20 knots
by mid afternoon. Waves subsiding to 2 to 4 feet.
.SUNDAY NIGHT...Northeast winds 5 to 15 knots veering southeast
after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...South winds 5 to 15 knots becoming northeast 15 to
25 knots. A chance of rain showers. Waves building to 2 to
4 feet.
.TUESDAY...North winds 20 to 30 knots diminishing to 15 to
25 knots. A chance of rain and snow showers. Waves building to
3 to 6 feet occasionally to 8 feet, then subsiding to 2 to
4 feet.

$$

LSZ265-191600-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
351 AM EDT Fri Apr 19 2024

...GALE WARNING IN EFFECT FROM 1 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT...

.EARLY THIS MORNING...West winds 15 to 25 knots. Waves 1 to
3 feet building to 2 to 4 feet.
.TODAY...West winds 20 to 30 knots with a few gale force gusts to
35 knots possible. Waves building to 4 to 7 feet occasionally to
9 feet.
.TONIGHT...West winds 20 to 30 knots. A slight chance of snow
showers after midnight. Waves subsiding to 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. Waves
subsiding to 2 to 4 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...West winds 20 to 30 knots becoming northwest 15 to
25 knots by mid afternoon. Waves subsiding to 1 to 3 feet.
.SUNDAY NIGHT...Northeast winds 10 to 20 knots veering southeast
after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...Southeast winds 10 to 20 knots becoming east 15 to
25 knots. Rain showers likely. Waves building to 1 to 3 feet.
.TUESDAY...North winds 20 to 30 knots. A chance of rain and snow
showers. Waves building to 3 to 6 feet occasionally to 8 feet.

$$

LSZ266-191600-
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-
351 AM EDT Fri Apr 19 2024

...GALE WARNING IN EFFECT FROM 1 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT...

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

$$

LSZ267-191600-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
351 AM EDT Fri Apr 19 2024

...GALE WARNING IN EFFECT FROM 1 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT...

.EARLY THIS MORNING...West winds 15 to 25 knots. Sprinkles and
flurries. Waves 2 to 4 feet.
.TODAY...West winds 15 to 25 knots increasing to gales to
35 knots in the afternoon. Sprinkles through early afternoon.
Waves building to 6 to 9 feet occasionally to 11 feet.
.TONIGHT...West winds 20 to 30 knots increasing to gales to
35 knots late. A slight chance of rain and snow showers after
midnight. Waves subsiding to 5 to 8 feet occasionally to 10 feet.
.SATURDAY...Northwest gales to 35 knots becoming west 20 to
30 knots 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. 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...North winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...Southeast winds 10 to 20 knots becoming south 15 to
25 knots. A chance of rain showers. Waves subsiding to calm to
2 feet, then building to 1 to 3 feet.
.TUESDAY...North winds 15 to 25 knots increasing to 20 to
30 knots. Rain showers likely. Waves building to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ261-191600-
MAFOR 1909/
Superior West...GALE WARNING IN EFFECT...11630 14640 19650 11640
11630 11740. Waves 5 to 8 feet building to 5 to 9 feet today.
Waves 5 to 8 feet subsiding to 3 to 6 feet tonight.

Superior North Central...GALE WARNING IN EFFECT...11630 11640
14650 19650 11640 11740. Waves 5 to 8 feet building to 7 to 11
feet today. Waves 7 to 11 feet subsiding to 5 to 8 feet tonight.

Superior South Central...GALE WARNING IN EFFECT...11630 15640
19650 11640. Waves 2 to 4 feet building to 5 to 7 feet today.
Waves 5 to 8 feet tonight.

Superior East...GALE WARNING IN EFFECT...11620 11630 14640 19650
11640 11630. Waves 3 to 6 feet building to 6 to 10 feet today.
Waves 6 to 10 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