Great Lakes Forecast
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FZUS63 KMQT 211454
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
954 AM EST Tue Nov 21 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 29.2 inch low pressure south of James Bay this
morning will continue to push off to the northeast, while a 30.5
inch high over the Canadian Plains today will drift south into
the Central Plains Wednesday morning and weaken to 30.2 inches as
it broadens over the Ohio Valley and Southern Plains on Wednesday
night. On Thursday morning, a 29.9 inch trough will settle south
across the Upper Great Lakes. A 30.0 inch ridge will then move
over the Upper Great Lakes Thursday night and into the Lower Great
Lakes on Friday morning. Meanwhile a 29.0 inch low will move to
Lake Winnipeg and track east across central and eastern Ontario
Friday evening. A 30.2 inch ridge will move into the northern
plains on Saturday.

LSZ162-212300-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
954 AM EST Tue Nov 21 2017 /854 AM CST Tue Nov 21 2017/

...GALE WARNING IN EFFECT UNTIL 5 PM EST /4 PM CST/ THIS
AFTERNOON...

.REST OF TODAY...Northwest gales to 35 knots diminishing to 20 to
30 knots by mid afternoon. Scattered snow showers. Waves 5 to
9 feet occasionally to 11 feet.
.TONIGHT...Northwest winds 20 to 30 knots diminishing to 15 to
25 knots by midnight, then becoming west 10 to 20 knots late.
Isolated snow showers in the evening. Waves subsiding to 1 to
3 feet.
.WEDNESDAY...West winds 10 to 20 knots becoming southwest 15 to
25 knots. Waves building to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY NIGHT...Southwest winds 15 to 25 knots becoming west
10 to 20 knots after midnight. A chance of snow showers. Waves
subsiding to 1 to 3 feet.
.THURSDAY...West winds 10 to 20 knots diminishing to 5 to
15 knots in the afternoon. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...Southwest winds 5 to 15 knots increasing to
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.FRIDAY...Southwest winds 20 to 30 knots with a few gale force
gusts to 35 knots in the afternoon. A chance of rain showers. A
chance of snow showers. Waves building to 4 to 7 feet occasionally
to 9 feet.
.SATURDAY...Northwest winds 20 to 30 knots diminishing to 15 to
25 knots. A chance of snow showers. Waves subsiding to 1 to
3 feet.

$$

LSZ263-212300-
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-
954 AM EST Tue Nov 21 2017

...GALE WARNING IN EFFECT UNTIL 5 PM EST THIS AFTERNOON...

.REST OF TODAY...Northwest gales to 40 knots diminishing to 20 to
30 knots by mid afternoon. Scattered snow showers. Waves 9 to
12 feet occasionally to 15 feet subsiding to 6 to 9 feet
occasionally to 11 feet.
.TONIGHT...Northwest winds 20 to 30 knots diminishing to 10 to
20 knots late. Isolated snow showers. Waves subsiding to 2 to
4 feet.
.WEDNESDAY...West winds 10 to 20 knots becoming southwest 15 to
25 knots by mid afternoon. A slight chance of snow showers in the
morning. Waves building to 3 to 6 feet occasionally to 8 feet.
.WEDNESDAY NIGHT...Southwest winds 15 to 25 knots veering west
after midnight. A chance of snow showers. Waves subsiding to 3 to
5 feet occasionally to 7 feet.
.THURSDAY...Northwest winds 10 to 20 knots becoming west 5 to
15 knots in the afternoon. Waves subsiding to calm to 2 feet.
.THURSDAY NIGHT...Southwest winds 5 to 15 knots increasing to
15 to 25 knots after midnight. Waves building to 2 to 4 feet.
.FRIDAY...Southwest winds 20 to 30 knots with a few gale force
gusts to 35 knots in the afternoon. A chance of rain showers. A
chance of snow showers. Waves building to 5 to 9 feet occasionally
to 11 feet.
.SATURDAY...Northwest winds 20 to 30 knots becoming north 15 to
25 knots. A chance of snow showers. Waves subsiding to 2 to
4 feet.

$$

LSZ264-212300-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
954 AM EST Tue Nov 21 2017

...GALE WARNING IN EFFECT THROUGH 10 PM EST THIS EVENING...

.REST OF TODAY...Northwest gales to 45 knots. Scattered snow
showers. Waves 9 to 12 feet occasionally to 15 feet building to
10 to 14 feet occasionally to 18 feet, then subsiding to 7 to
10 feet occasionally to 13 feet.
.TONIGHT...Northwest winds 20 to 30 knots with a few gale force
gusts to 35 knots diminishing to 15 to 25 knots late. Scattered
snow showers. Waves subsiding to 3 to 6 feet occasionally to 8
feet.
.WEDNESDAY...West winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. A slight chance of snow showers. Waves
subsiding to 2 to 4 feet, then building to 3 to 6 feet
occasionally to 8 feet.
.WEDNESDAY NIGHT...Southwest winds 15 to 25 knots veering west
after midnight. A chance of snow showers. Waves building to 4 to
7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.
.THURSDAY...Northwest winds 15 to 25 knots diminishing to 10 to
20 knots in the afternoon. Waves subsiding to 1 to 3 feet.
.THURSDAY NIGHT...South winds 5 to 15 knots increasing to 15 to
25 knots after midnight. A chance of snow showers. A chance of
rain showers after midnight. Waves subsiding to calm to 2 feet,
then building to 2 to 4 feet.
.FRIDAY...Southwest winds 20 to 30 knots with a few gale force
gusts to 35 knots. Rain showers likely, then a chance of rain
showers, possibly mixed with snow. Waves building to 7 to 10 feet
occasionally to 13 feet.
.SATURDAY...Northwest winds 20 to 30 knots with a few gale force
gusts to 35 knots becoming north 15 to 25 knots. A chance of snow
showers. Waves building to 8 to 11 feet occasionally to 14 feet,
then subsiding to 3 to 5 feet occasionally to 7 feet.

$$

LSZ265-212300-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
954 AM EST Tue Nov 21 2017

...GALE WARNING IN EFFECT THROUGH 10 PM EST THIS EVENING...

.REST OF TODAY...Northwest gales to 40 knots. Scattered snow
showers late in the morning, then numerous snow showers in the
afternoon. Waves 7 to 10 feet occasionally to 13 feet building to
10 to 14 feet occasionally to 18 feet, then subsiding to 8 to
11 feet occasionally to 14 feet.
.TONIGHT...Northwest gales to 35 knots diminishing to 20 to
30 knots by midnight. Scattered snow showers. Waves subsiding to
3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...West winds 15 to 25 knots backing southwest by mid
afternoon. A slight chance of snow showers in the morning. Waves
subsiding to 1 to 3 feet.
.WEDNESDAY NIGHT...Southwest winds 15 to 25 knots veering west
after midnight. A slight chance of snow showers. Waves building
to 2 to 4 feet.
.THURSDAY...West winds 20 to 30 knots becoming northwest 15 to
25 knots in the afternoon. Waves subsiding to 1 to 3 feet.
.THURSDAY NIGHT...Southwest winds 10 to 20 knots becoming south
15 to 25 knots after midnight. Waves subsiding to calm to 2 feet,
then building to 1 to 3 feet.
.FRIDAY...Southwest winds 20 to 30 knots with a few gale force
gusts to 35 knots in the afternoon. Rain showers likely, then a
chance of rain showers, possibly mixed with snow. Waves building
to 2 to 4 feet, then subsiding to 1 to 3 feet.
.SATURDAY...Northwest winds 20 to 30 knots with a few gale force
gusts to 35 knots in the morning. Snow showers likely, then a
chance of snow showers. Waves building to 8 to 11 feet
occasionally to 14 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ266-212300-
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-
954 AM EST Tue Nov 21 2017

...GALE WARNING IN EFFECT THROUGH 10 PM EST THIS EVENING...

.REST OF TODAY...Northwest gales to 45 knots. Numerous snow
showers. Waves 11 to 15 feet occasionally to 19 feet building to
12 to 17 feet occasionally to 21 feet, then subsiding to 11 to
15 feet occasionally to 19 feet.
.TONIGHT...Northwest gales to 40 knots diminishing to 20 to
30 knots late. Scattered snow showers. Waves subsiding to 5 to
8 feet occasionally to 10 feet.
.WEDNESDAY...West winds 15 to 25 knots backing southwest by mid
afternoon. A chance of snow showers. Waves subsiding to 3 to
6 feet occasionally to 8 feet.
.WEDNESDAY NIGHT...Southwest winds 15 to 25 knots veering west
after midnight. A chance of snow showers. Waves building to 4 to
7 feet occasionally to 9 feet.
.THURSDAY...West winds 20 to 30 knots becoming northwest 15 to
25 knots in the afternoon. A chance of snow showers. Waves
subsiding to 3 to 6 feet occasionally to 8 feet, then building to
4 to 7 feet occasionally to 9 feet.
.THURSDAY NIGHT...Northwest winds 10 to 20 knots becoming south
15 to 25 knots after midnight. A chance of snow showers. Waves
subsiding to 1 to 3 feet, then building to 2 to 4 feet.
.FRIDAY...South winds 20 to 30 knots with a few gale force gusts
to 35 knots in the afternoon. Rain showers likely, then a chance
of rain showers, possibly mixed with snow. Waves building to 9 to
12 feet occasionally to 15 feet.
.SATURDAY...Northwest winds 20 to 30 knots with a few gale force
gusts to 35 knots in the morning, then veering north in the
afternoon. Snow showers likely. Waves building to 10 to 14 feet
occasionally to 18 feet, then subsiding to 4 to 7 feet
occasionally to 9 feet.


$$

LSZ267-212300-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
954 AM EST Tue Nov 21 2017

...GALE WARNING IN EFFECT THROUGH 10 PM EST THIS EVENING...

.REST OF TODAY...West gales to 35 knots becoming northwest gales
to 45 knots. Numerous rain showers late in the morning. Numerous
snow showers. Waves 11 to 15 feet occasionally to 19 feet
building to 12 to 17 feet occasionally to 21 feet, then subsiding
to 11 to 15 feet occasionally to 19 feet.
.TONIGHT...Northwest gales to 35 knots diminishing to 15 to
25 knots. Numerous snow showers in the evening, then scattered
snow showers after midnight. Waves subsiding to 5 to 8 feet
occasionally to 10 feet.
.WEDNESDAY...Northwest winds 15 to 25 knots backing west. A
chance of snow showers. Waves subsiding to 3 to 5 feet
occasionally to 7 feet.
.WEDNESDAY NIGHT...Southwest winds 20 to 30 knots. A chance of
snow showers. Waves building to 3 to 6 feet occasionally to
8 feet.
.THURSDAY...West winds 20 to 30 knots veering northwest in the
afternoon. A chance of snow showers, possibly mixed with rain.
Waves building to 4 to 7 feet occasionally to 9 feet, then
subsiding to 3 to 6 feet occasionally to 8 feet.
.THURSDAY NIGHT...West winds 10 to 20 knots becoming south 15 to
25 knots after midnight. A chance of snow showers. Waves
subsiding to 1 to 3 feet, then building to 2 to 4 feet.
.FRIDAY...South winds 20 to 30 knots with a few gale force
gusts to 35 knots veering west. Rain showers likely. A chance of
snow showers. A chance of rain showers. Waves building to 9 to 12
feet occasionally to 15 feet.
.SATURDAY...Northwest winds 20 to 30 knots with a few gale force
gusts to 35 knots in the morning. Snow showers likely, then a
chance of snow showers. Waves building to 10 to 14 feet
occasionally to 18 feet, then subsiding to 3 to 6 feet
occasionally to 8 feet.

$$
LSZ261-212300-
MAFOR 2116/
Superior West...Gale Warning in effect...13750 11740 12730 12620.
Scattered snow showers late this morning. Waves 5 to 9 feet
through this evening subsiding to 3 to 6 feet tonight. Waves 1 to
4 feet Wednesday morning.

Superior North Central...Gale Warning in effect...11760 12750
12740 11730 11720 11620. Scattered snow showers this afternoon
through early evening tonight. Waves 9 to 13 feet this afternoon.
Waves 5 to 10 feet tonight. Waves 3 to 5 feet Wednesday morning.

Superior South Central...Gale Warning in effect...11767 12757
12740 12730 11620. Scattered snow showers from late evening
through tonight. Waves 10 to 15 feet this afternoon, subsiding to
5 to 9 feet tonight. Waves 3 to 6 feet Wednesday morning.

Superior East...Gale Warning in effect...11767 12757 11750 11740
12730 11720. Scattered snow showers from late evening through
Wednesday morning. Waves 11 to 16 feet this afternoon, subsiding
to 6 to 10 feet tonight. Waves 4 to 7 feet Wednesday morning.

$$

KCW

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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