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000
FZUS63 KMQT 182008
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
408 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 northwestern
Ontario at 29.8 inches this afternoon. This area of low pressure
slowly moves over far northern Ontario tonight and into James Bay
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.

LSZ162-190415-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
408 PM EDT Thu Apr 18 2024 /308 PM CDT Thu Apr 18 2024/

.LATE THIS AFTERNOON...Southwest winds 15 to 25 knots. Waves 3 to
6 feet occasionally to 8 feet.
.TONIGHT...West winds 15 to 25 knots. Waves building to 3 to
6 feet occasionally to 8 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.

$$

LSZ263-190415-
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-
408 PM EDT Thu Apr 18 2024

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

.LATE THIS AFTERNOON...West winds 15 to 25 knots. Waves 3 to
6 feet occasionally to 8 feet.
.TONIGHT...West winds 15 to 25 knots. Waves subsiding to 3 to
5 feet occasionally to 7 feet, then 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 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.

$$

LSZ264-190415-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
408 PM EDT Thu Apr 18 2024

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

.LATE THIS AFTERNOON...Southwest winds 15 to 25 knots. Waves 2 to
4 feet building to 3 to 5 feet occasionally to 7 feet.
.TONIGHT...Southwest winds 10 to 20 knots becoming west 15 to
25 knots after midnight. Waves 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. 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.

$$

LSZ265-190415-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
408 PM EDT Thu Apr 18 2024

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

.LATE THIS AFTERNOON...West winds 5 to 15 knots. A slight chance
of rain showers. Waves calm to 2 feet.
.TONIGHT...Southwest winds 5 to 15 knots becoming west 10 to
20 knots after midnight, then increasing to 15 to 25 knots late.
A slight chance of rain showers through midnight. Waves 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.

$$

LSZ266-190415-
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-
408 PM EDT Thu Apr 18 2024

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

.LATE THIS AFTERNOON...South winds 10 to 20 knots. A slight
chance of rain showers. Waves 1 to 3 feet building to 2 to
4 feet.
.TONIGHT...Southwest winds 10 to 20 knots veering west after
midnight, then increasing to 15 to 25 knots late. A chance of
rain showers through midnight. Sprinkles after midnight. Waves
building to 3 to 6 feet occasionally to 8 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.

$$

LSZ267-190415-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
408 PM EDT Thu Apr 18 2024

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

.LATE THIS AFTERNOON...South winds 5 to 15 knots. A slight chance
of rain showers. Waves 1 to 3 feet.
.TONIGHT...South winds 5 to 15 knots becoming west 10 to 20 knots
after midnight. A chance of rain showers. Waves building to 2 to
4 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.

$$

LSZ261-190415-
MAFOR 1821/
Superior West...GALE WARNING IN EFFECT...14630 11630 13640. Waves
3 to 6 feet tonight building to 5 to 9 feet Friday.

Superior North Central...GALE WARNING IN EFFECT...12530 11620
12630 12640 11650. Waves 3 to 6 feet tonight building to 7 to 11
feet Friday.

Superior South Central...GALE WARNING IN EFFECT...12500 11510
11620 11630 12640 11650. Waves 1 to 2 feet building to 2 to 4
feet tonight then building to 4 to 7 feet Friday.

Superior East...GALE WARNING IN EFFECT...12400 11500 11520 12630
11640 11650. A chance of rain showers tonight. Waves 2 to 4 feet
tonight building to 6 to 9 feet Friday.

$$

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