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000
FZUS63 KMQT 190146
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
946 PM EDT Thu Apr 18 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 29.8 inches this evening. This area of low
pressure slowly moves over far northern Ontario overnight 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.

LSZ162-191000-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
946 PM EDT Thu Apr 18 2024 /846 PM CDT Thu Apr 18 2024/

.REST OF TONIGHT...West winds 15 to 25 knots increasing to 20 to
30 knots late. Waves 3 to 5 feet occasionally to 7 feet building
to 4 to 7 feet occasionally to 9 feet.
.FRIDAY...West winds 20 to 30 knots increasing to 30 knots with a
few gale force gusts to 35 knots possible late. Waves building to
5 to 8 feet occasionally to 10 feet, then subsiding to 3 to
6 feet occasionally to 8 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots veering northwest late.
Waves subsiding to 3 to 5 feet occasionally to 7 feet.
.SATURDAY...Northwest winds 15 to 25 knots backing west by mid
afternoon. Waves subsiding to 2 to 4 feet, then building to 3 to
5 feet occasionally to 7 feet.
.SATURDAY NIGHT...West winds 15 to 25 knots. Waves subsiding to
2 to 4 feet.
.SUNDAY...West winds 15 to 25 knots. Waves building to 3 to
6 feet occasionally to 8 feet, then subsiding to 2 to 4 feet.
.SUNDAY NIGHT...Northwest winds 10 to 20 knots becoming east 5 to
15 knots after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...East winds 10 to 20 knots becoming northeast 15 to
25 knots. A chance of rain showers. Waves building to 3 to 5 feet
occasionally to 7 feet.
.TUESDAY...Northeast winds 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 1 to 3 feet.

$$

LSZ263-191000-
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-
946 PM EDT Thu Apr 18 2024

...GALE WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
EVENING...

.REST OF TONIGHT...West winds 20 to 30 knots diminishing to 15 to
25 knots after midnight. Waves 3 to 6 feet occasionally to 8 feet
building to 5 to 8 feet occasionally to 10 feet.
.FRIDAY...West winds 20 to 30 knots increasing to gales to
35 knots in the afternoon. Waves building to 7 to 11 feet
occasionally to 14 feet.
.FRIDAY NIGHT...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 by mid
afternoon. 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 10 to 20 knots increasing to 15 to
25 knots after midnight. 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 3 to 5 feet occasionally to
7 feet.
.SUNDAY NIGHT...East winds 5 to 15 knots veering southeast after
midnight. Waves subsiding to calm to 2 feet.
.MONDAY...East winds 5 to 15 knots becoming northeast 15 to
25 knots. A chance of rain showers. A chance of snow showers.
Waves building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...Northeast winds 15 to 25 knots diminishing to 10 to
20 knots. A chance of rain and snow showers. Waves building to
3 to 6 feet occasionally to 8 feet, then subsiding to 1 to
3 feet.

$$

LSZ264-191000-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
946 PM EDT Thu Apr 18 2024

...GALE WARNING IN EFFECT FROM FRIDAY MORNING THROUGH FRIDAY
EVENING...

.REST OF TONIGHT...West winds 10 to 20 knots increasing to 15 to
25 knots late. Waves 4 to 8 feet occasionally to 10 feet.
.FRIDAY...West winds 20 to 30 knots increasing to gales to
35 knots in the afternoon. A slight chance of rain and snow
showers by mid afternoon. Waves building to 8 to 11 feet
occasionally to 14 feet.
.FRIDAY NIGHT...West gales to 35 knots diminishing to 20 to
30 knots after midnight, then 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 by mid
afternoon. 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. Waves subsiding to
3 to 6 feet occasionally to 8 feet.
.SUNDAY...West winds 15 to 25 knots. Waves building to 4 to
7 feet occasionally to 9 feet, then subsiding to 3 to 5 feet
occasionally to 7 feet.
.SUNDAY NIGHT...North winds 10 to 20 knots becoming south 5 to
15 knots 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, possibly mixed with snow.
Waves building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY...North winds 15 to 25 knots diminishing to 10 to
20 knots. Waves building to 3 to 6 feet occasionally to 8 feet,
then subsiding to 1 to 3 feet.

$$

LSZ265-191000-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
946 PM EDT Thu Apr 18 2024

...GALE WARNING IN EFFECT FROM FRIDAY AFTERNOON THROUGH LATE
FRIDAY NIGHT...

.REST OF TONIGHT...Southwest winds 10 to 20 knots becoming west
15 to 25 knots after midnight. A slight chance of rain showers by
late evening. Waves calm to 2 feet building to 2 to 4 feet.
.FRIDAY...West winds 20 to 30 knots. Waves building to 4 to
7 feet occasionally to 9 feet.
.FRIDAY NIGHT...West winds 20 to 30 knots increasing to gales to
35 knots after midnight. A slight chance of rain showers. Waves
subsiding to 3 to 6 feet occasionally to 8 feet.
.SATURDAY...Northwest winds 20 to 30 knots becoming west 15 to
25 knots by mid afternoon. 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 2 to 4 feet.
.SUNDAY...West winds 15 to 25 knots veering northwest by mid
afternoon. Waves subsiding to calm to 2 feet.
.SUNDAY NIGHT...North winds 10 to 20 knots veering south after
midnight. Waves calm to 2 feet.
.MONDAY...Northeast winds 10 to 20 knots increasing to 15 to
25 knots. A chance of rain showers. Waves building to 1 to
3 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 5 feet occasionally to 7 feet, then subsiding to 2 to
4 feet.

$$

LSZ266-191000-
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-
946 PM EDT Thu Apr 18 2024

...GALE WARNING IN EFFECT FROM FRIDAY AFTERNOON THROUGH LATE
FRIDAY NIGHT...

.REST OF TONIGHT...Southwest winds 10 to 20 knots becoming west
15 to 25 knots after midnight, then diminishing to 10 to 20 knots
late. A chance of rain showers by late evening. Sprinkles after
midnight. Waves 3 to 5 feet occasionally to 7 feet building to
4 to 7 feet occasionally to 9 feet.
.FRIDAY...West winds 20 to 30 knots increasing to gales to
35 knots in the afternoon. Waves building to 9 to 12 feet
occasionally to 15 feet.
.FRIDAY NIGHT...West gales to 35 knots. A slight chance of rain
showers after midnight. Waves subsiding to 5 to 8 feet
occasionally to 10 feet, then building to 6 to 9 feet
occasionally to 11 feet.
.SATURDAY...Northwest gales to 35 knots becoming west 20 to
30 knots by mid afternoon. Waves 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.
.SUNDAY...West winds 20 to 30 knots veering northwest by mid
afternoon. Waves building to 4 to 7 feet occasionally to 9 feet,
then subsiding to 3 to 6 feet occasionally to 8 feet.
.SUNDAY NIGHT...North winds 10 to 20 knots backing southwest
after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 10 to 20 knots backing northeast. 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 showers. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 2 to 4 feet.

$$

LSZ267-191000-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
946 PM EDT Thu Apr 18 2024

...GALE WARNING IN EFFECT FROM FRIDAY AFTERNOON THROUGH LATE
FRIDAY NIGHT...

.REST OF TONIGHT...Southeast winds 10 to 20 knots veering west
after midnight. A chance of rain showers. Waves 1 to 3 feet
subsiding to calm to 2 feet, then building to 3 to 5 feet
occasionally to 7 feet.
.FRIDAY...West winds 15 to 25 knots increasing to gales to
40 knots in the afternoon. Waves building to 7 to 10 feet
occasionally to 13 feet.
.FRIDAY NIGHT...West gales to 35 knots. A slight chance of rain
showers. A slight chance of snow showers after midnight. Waves
subsiding to 6 to 9 feet occasionally to 11 feet.
.SATURDAY...Northwest gales to 35 knots backing west by mid
afternoon. A slight chance of snow showers through early
afternoon. Waves subsiding to 5 to 8 feet occasionally to
10 feet.
.SATURDAY NIGHT...West winds 15 to 25 knots. Waves subsiding to
3 to 6 feet occasionally to 8 feet.
.SUNDAY...West winds 20 to 30 knots veering northwest by mid
afternoon. Waves building to 4 to 7 feet occasionally to 9 feet,
then subsiding to 3 to 6 feet occasionally to 8 feet.
.SUNDAY NIGHT...Northwest winds 10 to 20 knots backing west after
midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...Southwest winds 10 to 20 knots becoming east 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. A chance of rain showers. Waves building to 2 to
4 feet.

$$
LSZ261-191000-
MAFOR 1903/
Superior West...GALE WARNING IN EFFECT...13630 14640 11640. Waves
3 to 6 feet overnight building to 6 to 9 feet Friday and Friday
evening.

Superior North Central...GALE WARNING IN EFFECT...11620 12630
12640 13650. Waves 4 to 7 feet overnight building to 7 to 11 feet
Friday and Friday evening.

Superior South Central...GALE WARNING IN EFFECT...13630 12640
11650 11640 11650. Waves 1 to 3 feet building to 2 to 4 feet
overnight. Waves 3 to 5 feet building to 5 to 8 feet Friday and
Friday evening.

Superior East...GALE WARNING IN EFFECT...11510 12620 11630 11640
13650. A chance of rain showers overnight. Waves 2 to 3 feet
building to 3 to 5 feet overnight. Waves 5 to 8 feet building to
7 to 11 feet Friday and Friday evening.

$$

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