Great Lakes Forecast
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954
FZUS63 KMQT 201459
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
959 AM EST Mon Nov 20 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 29.9 inch ridge of high pressure over the upper
Great Lakes this morning will move to the lower Great Lakes this
afternoon. A 29.3 inch low pressure over southern Saskatchewan
this morning will deepen to 29.1 inches as it moves north of Lake
Superior tonight and reaches James Bay by Tuesday afternoon. A
30.5 inch high over the northern plains Tuesday evening will drift
south into the Central Plains Wednesday morning and weaken to
30.3 inches over the Ohio Valley Thursday morning as a 29.8 inch
trough moves through the upper Great Lakes. A 30.0 inch ridge will
move over the upper Great Lakes Thursday night and into the lower
Great Lakes Friday morning. A 29.1 inch low will move to Lake
Winnipeg Friday morning and deepen to 29.0 inches as it moves
across central Ontario Friday evening.

LSZ162-202300-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
959 AM EST Mon Nov 20 2017 /859 AM CST Mon Nov 20 2017/

...GALE WARNING IN EFFECT FROM THIS EVENING THROUGH TUESDAY
AFTERNOON...

.REST OF TODAY...South winds 5 to 15 knots increasing to 15 to
25 knots by mid afternoon. Waves calm to 2 feet.
.TONIGHT...Southwest gales to 35 knots becoming west gales to
40 knots by midnight. Isolated snow showers after midnight. Waves
building to 7 to 10 feet occasionally to 13 feet.
.TUESDAY...Northwest gales to 35 knots diminishing to 20 to
30 knots by mid afternoon. A chance of snow showers. Waves
subsiding to 4 to 7 feet occasionally to 9 feet.
.TUESDAY NIGHT...Northwest winds 20 to 30 knots diminishing to
10 to 20 knots after midnight. A slight chance of snow showers.
Waves subsiding to 1 to 3 feet.
.WEDNESDAY...West winds 10 to 20 knots. Waves building to 2 to
4 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots. Waves building to
3 to 5 feet occasionally to 7 feet, then subsiding to 2 to
4 feet.
.THURSDAY...Northwest winds 10 to 20 knots backing south. Waves
subsiding to calm to 2 feet.
.FRIDAY...Southwest winds 15 to 25 knots becoming west 20 to
30 knots. A chance of rain showers, possibly mixed with snow.
Waves building to 4 to 7 feet occasionally to 9 feet.

$$

LSZ263-202300-
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-
959 AM EST Mon Nov 20 2017

...GALE WARNING IN EFFECT FROM THIS EVENING THROUGH TUESDAY
AFTERNOON...

.REST OF TODAY...South winds 5 to 15 knots increasing to 10 to
20 knots by mid afternoon. Waves calm to 2 feet building to 1 to
3 feet.
.TONIGHT...Southwest gales to 35 knots becoming west gales to
40 knots by midnight. Scattered snow and rain showers after
midnight. Waves building to 9 to 12 feet occasionally to 15 feet.
.TUESDAY...Northwest gales to 35 knots diminishing to 20 to
30 knots by mid afternoon. A chance of snow showers. Waves
subsiding to 5 to 8 feet occasionally to 10 feet.
.TUESDAY NIGHT...Northwest winds 20 to 30 knots diminishing to
15 to 25 knots after midnight. A chance of snow showers. Waves
subsiding to 2 to 4 feet.
.WEDNESDAY...West winds 10 to 20 knots. Waves subsiding to 1 to
3 feet, then building to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots. Waves building to
3 to 6 feet occasionally to 8 feet.
.THURSDAY...Northwest winds 15 to 25 knots becoming south 10 to
20 knots. Waves subsiding to calm to 2 feet.
.FRIDAY...Southwest winds 20 to 30 knots becoming west gales to
35 knots. A chance of rain showers, possibly mixed with snow.
Waves building to 6 to 9 feet occasionally to 11 feet.

$$

LSZ264-202300-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
959 AM EST Mon Nov 20 2017

...GALE WARNING IN EFFECT FROM THIS EVENING THROUGH TUESDAY
EVENING...

.REST OF TODAY...South winds 5 to 15 knots increasing to 15 to
25 knots. Waves calm to 2 feet building to 3 to 5 feet
occasionally to 7 feet.
.TONIGHT...South gales to 35 knots veering west by midnight.
Scattered snow and rain showers after midnight. Waves building to
9 to 12 feet occasionally to 15 feet.
.TUESDAY...Northwest gales to 40 knots. A chance of snow showers.
Waves subsiding to 8 to 11 feet occasionally to 14 feet, then
building to 9 to 12 feet occasionally to 15 feet.
.TUESDAY NIGHT...Northwest gales to 35 knots diminishing to 15 to
25 knots after midnight. A chance of snow showers. Waves
subsiding to 3 to 6 feet occasionally to 8 feet.
.WEDNESDAY...West winds 10 to 20 knots. Waves subsiding to 2 to
4 feet, then building to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots. Waves building to
4 to 7 feet occasionally to 9 feet.
.THURSDAY...Northwest winds 15 to 25 knots becoming southwest
10 to 20 knots. Waves subsiding to 1 to 3 feet.
.FRIDAY...Southwest winds 20 to 30 knots becoming west gales to
35 knots. Rain and snow showers likely, then a chance of rain and
snow showers. Waves building to 7 to 10 feet occasionally to
13 feet.

$$

LSZ265-202300-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
959 AM EST Mon Nov 20 2017

...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH TUESDAY
EVENING...

.REST OF TODAY...South winds 10 to 20 knots increasing to 15 to
25 knots by mid afternoon. Waves calm to 2 feet building to 2 to
4 feet.
.TONIGHT...Southwest winds 20 to 30 knots increasing to gales to
35 knots by midnight, then veering west late. Scattered rain
showers, possibly mixed with snow after midnight. Waves building
to 5 to 8 feet occasionally to 10 feet.
.TUESDAY...West gales to 40 knots veering northwest. A chance of
snow showers, possibly mixed with rain in the morning, then snow
showers likely in the afternoon. Waves building to 8 to 12 feet
occasionally to 15 feet.
.TUESDAY NIGHT...Northwest gales to 35 knots diminishing to 20 to
30 knots after midnight. A chance of snow showers. Waves
subsiding to 3 to 6 feet occasionally to 8 feet.
.WEDNESDAY...West winds 15 to 25 knots. A chance of snow showers.
Waves subsiding to 1 to 3 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots increasing to 20 to
30 knots after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.THURSDAY...Northwest winds 20 to 30 knots becoming southwest
10 to 20 knots. A chance of snow showers. Waves subsiding to calm
to 2 feet.
.FRIDAY...Southwest winds 20 to 30 knots becoming west gales to
35 knots. A chance of rain showers, possibly mixed with snow.
Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet.

$$

LSZ266-202300-
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-
959 AM EST Mon Nov 20 2017

...GALE WARNING IN EFFECT FROM LATE TONIGHT THROUGH TUESDAY
EVENING...

.REST OF TODAY...South winds 10 to 20 knots increasing to 20 to
30 knots. Waves 1 to 3 feet building to 3 to 5 feet occasionally
to 7 feet.
.TONIGHT...South gales to 35 knots veering west late. Scattered
rain showers after midnight. Waves building to 8 to 11 feet
occasionally to 14 feet.
.TUESDAY...West gales to 40 knots becoming northwest gales to
45 knots. A chance of rain showers in the morning. Snow showers
likely. Waves building to 11 to 15 feet occasionally to 19 feet,
then subsiding to 10 to 14 feet occasionally to 18 feet.
.TUESDAY NIGHT...Northwest gales to 35 knots diminishing to 20 to
30 knots after midnight. Snow showers likely. Waves subsiding to
5 to 8 feet occasionally to 10 feet.
.WEDNESDAY...Northwest winds 15 to 25 knots backing west in the
afternoon. A chance of snow showers. Waves subsiding to 2 to
4 feet.
.WEDNESDAY NIGHT...West winds 15 to 25 knots. A chance of snow
showers. Waves building to 4 to 7 feet occasionally to 9 feet.
.THURSDAY...Northwest winds 20 to 30 knots becoming southwest
10 to 20 knots. A chance of snow showers. Waves building to 5 to
8 feet occasionally to 10 feet, then subsiding to 1 to 3 feet.
.FRIDAY...South winds 20 to 30 knots becoming west gales to
35 knots. A chance of rain showers, possibly mixed with snow.
Waves building to 4 to 8 feet occasionally to 10 feet.

$$

LSZ267-202300-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
959 AM EST Mon Nov 20 2017

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

.REST OF TODAY...Southwest winds 10 to 20 knots becoming south
15 to 25 knots by late morning, then increasing to 20 to 30 knots
by mid afternoon. Isolated rain and snow showers late in the
morning. Waves 2 to 4 feet subsiding to 1 to 3 feet, then
building to 2 to 4 feet.
.TONIGHT...South gales to 35 knots veering southwest by midnight.
Scattered rain showers after midnight. Waves building to 5 to
8 feet occasionally to 10 feet.
.TUESDAY...West gales to 35 knots becoming northwest gales to
40 knots. Rain showers likely in the morning. Snow showers
likely. Waves building to 10 to 14 feet occasionally to 18 feet.
.TUESDAY NIGHT...Northwest gales to 35 knots diminishing to 20 to
30 knots after midnight. Snow showers likely. Waves subsiding to
5 to 8 feet occasionally to 10 feet.
.WEDNESDAY...Northwest winds 15 to 25 knots backing west in the
afternoon. A chance of snow showers. Waves subsiding to 3 to
5 feet occasionally to 7 feet.
.WEDNESDAY NIGHT...Southwest winds 15 to 25 knots becoming west
20 to 30 knots after midnight. A chance of snow showers. Waves
subsiding to 2 to 4 feet, then building to 3 to 6 feet
occasionally to 8 feet.
.THURSDAY...Northwest winds 20 to 30 knots diminishing to 10 to
20 knots. A chance of snow showers. Waves building to 5 to 8 feet
occasionally to 10 feet, then subsiding to 1 to 3 feet.
.FRIDAY...South winds 20 to 30 knots becoming west gales to
35 knots. A chance of rain showers. A chance of snow showers.
Rain showers likely. Waves building to 9 to 12 feet occasionally
to 15 feet.

$$
LSZ261-202300-
MAFOR 2016/
Superior West...Gale Warning in effect...12410 11540 11550 13650
11750. Chance of snow showers Tuesday morning. Waves 1 to 4 feet
building to 7 to 10 feet tonight. Waves 8 to 11 feet subsiding to
6 to 9 feet Tuesday morning.

Superior North Central...Gale Warning in effect...12420 11440
12550 12650 11750. Scattered snow and rain showers through mid
morning, then chance of snow showers late Tuesday morning. Waves
1 to 6 feet building to 7 to 11 feet tonight. Waves 8 to 11 feet
Tuesday morning.

Superior South Central...Gale Warning in effect...12420 11440
11540 11550 13650. Scattered rain showers late tonight with a
chance of snow showers through mid Tuesday morning, then chance
of snow showers late Tuesday morning. Waves 1 to 4 feet building
to 5 to 8 feet tonight. Waves 6 to 10 feet Tuesday morning.

Superior East...Gale Warning in effect...11420 11430 11440 11450
12540 11650 11656. Chance of snow showers through mid Tuesday
morning. Waves 2 to 4 feet this afternoon building to 5 to 8 feet
tonight. Waves 8 to 12 feet Tuesday morning.

$$

JSS

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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