Great Lakes Forecast
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FZUS63 KMQT 240814
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
414 AM EDT Tue Oct 24 2017

For waters beyond five 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 low pressure of 29.1 inches over far northeast Lower
Michigan will lift into far eastern Upper Michigan today while
deepening to 28.9 inches. The low will then weaken to 29.3 inches
while drifting east to just north of Georgian Bay by Wednesday
morning. As the low lifts into Quebec on Wednesday, a 29.8 inch
high pressure ridge will build southeast to Lake Superior.
Another low pressure of 29.5 inches over the Northern Plains
Wednesday evening will then track east, reaching the Upper Great
Lakes Thursday night and Friday. The low will weaken to 29.7
inches as it moves very slowly to the east on Saturday.

LSZ162-241615-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
414 AM EDT Tue Oct 24 2017 /314 AM CDT Tue Oct 24 2017/

...GALE WARNING IN EFFECT THROUGH LATE TONIGHT...

.EARLY THIS MORNING...North gales to 45 knots. Scattered showers.
Waves 6 to 9 feet occasionally to 11 feet building to 8 to
11 feet occasionally to 14 feet.
.TODAY...North gales to 45 knots becoming northwest gales to
40 knots late. Scattered rain showers. Waves building to 9 to
12 feet occasionally to 15 feet, then subsiding to 6 to 9 feet
occasionally to 11 feet.
.TONIGHT...Northwest winds 20 to 30 knots diminishing to 10 to
20 knots. Isolated rain and snow showers after midnight. Waves
subsiding to calm to 2 feet.
.WEDNESDAY...North winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon, then veering south late. A slight
chance of rain showers through early afternoon. Waves calm to
2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots increasing to
10 to 20 knots after midnight. A slight chance of rain showers
after midnight. Waves building to 1 to 3 feet.
.THURSDAY...Southeast winds 15 to 25 knots backing east by mid
afternoon. Showers. Waves building to 3 to 5 feet occasionally to
7 feet.
.THURSDAY NIGHT...East winds 20 to 30 knots backing northeast
after midnight. Rain showers. Waves building to 5 to 8 feet
occasionally to 10 feet.
.FRIDAY...Northeast gales to 35 knots backing north. Rain showers
likely, then a chance of rain showers. Waves building to 10 to
14 feet occasionally to 18 feet, then subsiding to 6 to 9 feet
occasionally to 11 feet.
.SATURDAY...North winds 20 to 30 knots diminishing to 15 to
25 knots. Waves subsiding to 3 to 5 feet occasionally to 7 feet.

$$

LSZ263-241615-
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-
414 AM EDT Tue Oct 24 2017

...STORM WARNING IN EFFECT THROUGH THIS EVENING...

.EARLY THIS MORNING...North gales to 45 knots. Scattered showers.
Waves 6 to 9 feet occasionally to 11 feet building to 9 to
12 feet occasionally to 15 feet.
.TODAY...North storm force winds to 55 knots. Numerous rain
showers through early afternoon, then scattered rain showers by
mid afternoon. Waves building to 12 to 17 feet occasionally to
21 feet, then subsiding to 10 to 14 feet occasionally to 18 feet.
.TONIGHT...North gales to 40 knots becoming northwest 20 to
30 knots after midnight, then becoming north 10 to 20 knots late.
Isolated rain showers through midnight. Waves subsiding to 3 to
5 feet occasionally to 7 feet.
.WEDNESDAY...North winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon. A slight chance of rain showers
through early afternoon. Waves subsiding to calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots increasing to
10 to 20 knots after midnight. A slight chance of rain showers
after midnight. Waves building to 1 to 3 feet.
.THURSDAY...Southeast winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. A chance of rain showers through early
afternoon, then rain showers by mid afternoon. Waves building to
3 to 5 feet occasionally to 7 feet.
.THURSDAY NIGHT...East winds 20 to 30 knots backing northeast
after midnight. Rain showers. Waves building to 6 to 9 feet
occasionally to 11 feet.
.FRIDAY...Northeast gales to 35 knots. Rain showers, then a
chance of rain showers, possibly mixed with snow. Waves building
to 9 to 12 feet occasionally to 15 feet, then subsiding to 7 to
10 feet occasionally to 13 feet.
.SATURDAY...North winds 20 to 30 knots diminishing to 15 to
25 knots. A chance of rain showers, possibly mixed with snow.
Waves subsiding to 3 to 6 feet occasionally to 8 feet.

$$

LSZ264-241615-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
414 AM EDT Tue Oct 24 2017

...STORM WARNING IN EFFECT THROUGH THIS EVENING...

.EARLY THIS MORNING...North gales to 45 knots. Showers. Waves
4 to 7 feet occasionally to 9 feet building to 9 to 12 feet
occasionally to 15 feet.
.TODAY...North storm force winds to 60 knots. Rain showers. Waves
building to 17 to 22 feet occasionally to 28 feet, then subsiding
to 15 to 20 feet occasionally to 25 feet.
.TONIGHT...North gales to 45 knots diminishing to 20 to 30 knots
late. Scattered rain showers. Isolated snow showers after
midnight. Waves subsiding to 4 to 7 feet occasionally to 9 feet.
.WEDNESDAY...North winds 15 to 25 knots diminishing to 5 to
15 knots. Waves subsiding to 1 to 3 feet.
.WEDNESDAY NIGHT...East winds 5 to 15 knots veering southeast
after midnight. A slight chance of rain showers after midnight.
Waves subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. A chance of rain showers through early
afternoon, then rain showers likely by mid afternoon. Waves
building to 3 to 5 feet occasionally to 7 feet.
.THURSDAY NIGHT...East winds 20 to 30 knots increasing to gales
to 35 knots after midnight. Rain showers. Waves building to 6 to
9 feet occasionally to 11 feet.
.FRIDAY...Northeast gales to 35 knots. Rain showers. Waves
building to 9 to 12 feet occasionally to 15 feet, then subsiding
to 7 to 10 feet occasionally to 13 feet.
.SATURDAY...Northeast winds 20 to 30 knots. A chance of rain
showers. Waves subsiding to 3 to 6 feet occasionally to 8 feet.

$$

LSZ265-241615-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
414 AM EDT Tue Oct 24 2017

...STORM WARNING IN EFFECT THROUGH THIS EVENING...

.EARLY THIS MORNING...North storm force winds to 50 knots.
Showers. Waves 5 to 8 feet occasionally to 10 feet building to
10 to 14 feet occasionally to 18 feet.
.TODAY...North storm force winds to 60 knots. Showers. Waves
building to 20 to 25 feet occasionally to 31 feet, then subsiding
to 17 to 22 feet occasionally to 28 feet.
.TONIGHT...North gales to 45 knots becoming northwest gales to
40 knots after midnight, then diminishing to 20 to 30 knots late.
Numerous rain showers through midnight, then scattered rain and
snow showers after midnight. Waves subsiding to 6 to 9 feet
occasionally to 11 feet.
.WEDNESDAY...North winds 15 to 25 knots diminishing to 10 to
20 knots late. A slight chance of rain showers through early
afternoon. Waves subsiding to 2 to 4 feet.
.WEDNESDAY NIGHT...Northeast winds 5 to 15 knots veering
southeast after midnight. Waves subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. A chance of rain showers. Waves
building to 2 to 4 feet.
.THURSDAY NIGHT...East winds 20 to 30 knots increasing to gales
to 35 knots after midnight. Showers. Waves building to 4 to
7 feet occasionally to 9 feet.
.FRIDAY...East winds 20 to 30 knots becoming northeast gales to
35 knots. Rain showers. Waves building to 9 to 12 feet
occasionally to 15 feet, then subsiding to 5 to 8 feet
occasionally to 10 feet.
.SATURDAY...Northeast winds 20 to 30 knots backing north. Rain
showers likely. Waves building to 6 to 9 feet occasionally to
11 feet, then subsiding to 4 to 7 feet occasionally to 9 feet.

$$

LSZ266-241615-
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-
414 AM EDT Tue Oct 24 2017

...STORM WARNING IN EFFECT THROUGH THIS EVENING...

.EARLY THIS MORNING...North storm force winds to 60 knots.
Showers. Waves 10 to 14 feet occasionally to 18 feet building to
12 to 17 feet occasionally to 21 feet.
.TODAY...North storm force winds to 60 knots. Showers. Waves
building to 22 to 27 feet occasionally to 34 feet, then subsiding
to 20 to 25 feet occasionally to 31 feet.
.TONIGHT...North storm force winds to 55 knots diminishing to
gales to 45 knots after midnight. Rain showers through midnight,
then scattered rain and snow showers after midnight. Waves
subsiding to 8 to 11 feet occasionally to 14 feet.
.WEDNESDAY...North winds 20 to 30 knots diminishing to 15 to
25 knots in the afternoon. A slight chance of rain showers
through early afternoon. Waves subsiding to 2 to 4 feet.
.WEDNESDAY NIGHT...Northeast winds 5 to 15 knots veering east
after midnight. Waves subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. A chance of rain showers. Waves
building to 2 to 4 feet.
.THURSDAY NIGHT...East winds 20 to 30 knots increasing to gales
to 35 knots after midnight. Showers. Waves building to 5 to
8 feet occasionally to 10 feet.
.FRIDAY...East gales to 35 knots. Rain showers. Waves building to
8 to 11 feet occasionally to 14 feet, then subsiding to 6 to
9 feet occasionally to 11 feet.
.SATURDAY...Northeast winds 20 to 30 knots. Rain showers likely.
Waves subsiding to 5 to 8 feet occasionally to 10 feet, then
building to 6 to 9 feet occasionally to 11 feet.

$$

LSZ267-241615-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
414 AM EDT Tue Oct 24 2017

...STORM WARNING IN EFFECT THROUGH THIS EVENING...

.EARLY THIS MORNING...North storm force winds to 55 knots.
Showers. Waves 10 to 14 feet occasionally to 18 feet building to
12 to 17 feet occasionally to 21 feet.
.TODAY...North storm force winds to 55 knots diminishing to gales
to 45 knots in the afternoon, then increasing to storm force
winds to 55 knots late. Showers. Waves building to 15 to 20 feet
occasionally to 25 feet.
.TONIGHT...North storm force winds to 55 knots diminishing to
gales to 45 knots after midnight. Rain showers. Scattered snow
showers after midnight. Waves subsiding to 8 to 11 feet
occasionally to 14 feet.
.WEDNESDAY...North winds 20 to 30 knots diminishing to 15 to
25 knots late. A chance of rain showers. Waves subsiding to 2 to
4 feet.
.WEDNESDAY NIGHT...Northeast winds 10 to 20 knots becoming east
5 to 15 knots after midnight. A slight chance of rain showers
through midnight. Waves subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots backing east by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...East winds 15 to 25 knots increasing to 20 to
30 knots after midnight. A chance of showers through midnight,
then showers likely after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.FRIDAY...East gales to 35 knots diminishing to 15 to 25 knots.
Rain showers. Waves building to 5 to 8 feet occasionally to
10 feet, then subsiding to 2 to 4 feet.
.SATURDAY...Northeast winds 15 to 25 knots. Rain showers likely.
Waves building to 4 to 7 feet occasionally to 9 feet, then
subsiding to 3 to 5 feet occasionally to 7 feet.

$$

LSZ261-241615-
MAFOR 2409/
Superior West...Gale Warning in effect...13860 11850 12750 11740
11730. Scattered showers this morning. Waves today 6 to 9 feet
building to 9 to 13 feet then subsiding to 8 to 11 feet, then
subsiding to 3 to 5 feet tonight.

Superior North Central...Storm Warning in effect...11866 11876
11886 12876 11866 11850 11840. Waves 5 to 7 feet building to 15
to 20 feet today. Waves 14 to 18 feet subsiding to 7 to 10 feet
tonight.

Superior South Central...Storm Warning in effect...11876 12886
13876 11866 11750. Scattered showers after midnight. Scattered
snow and rain showers late tonight. Waves 6 to 9 feet building to
21 to 26 feet today. Waves 18 to 23 feet subsiding to 10 to 14
feet tonight.

Superior East...Storm Warning in effect...15876 11866 11857.
Scattered showers late tonight. Waves 10 to 13 feet building to
15 to 20 feet today. Waves 15 to 19 feet subsiding to 10 to 14
feet tonight.

$$

Rolfson

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

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



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