Great Lakes Forecast
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FZUS63 KMQT 211952
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
352 PM EDT Sat Oct 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 29.7 inch trough will pass across Lake Superior
tonight. Weak ridging of 30.0 inches will track eastward across
Lake Superior late Sunday ahead of a 29.7 inch trough that will
cross Lake Superior Monday. A strong low pressure system of 29.3
inches will track along the backside of the trough northward
toward eastern Ontario Tuesday. Brief ridging on Wednesday will
give way to another trough on Thursday into Friday.

LSZ162-220400-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
352 PM EDT Sat Oct 21 2017 /252 PM CDT Sat Oct 21 2017/

.LATE THIS AFTERNOON...South winds 15 to 25 knots. Isolated
showers and thunderstorms. Waves 1 to 3 feet.
.TONIGHT...South winds 10 to 20 knots increasing to 15 to
25 knots after midnight, then veering southwest late. A slight
chance of showers and thunderstorms. Waves subsiding to calm to 2
feet, then building to 3 to 5 feet occasionally to 7 feet.
.SUNDAY...Southwest winds 15 to 25 knots veering west in the
afternoon, then backing southwest late. A slight chance of
showers through early afternoon. Waves 3 to 5 feet occasionally
to 7 feet.
.SUNDAY NIGHT...Southwest winds 15 to 25 knots increasing to
20 to 30 knots after midnight. A slight chance of showers after
midnight. Waves subsiding to 2 to 4 feet.
.MONDAY...Southwest winds 15 to 25 knots veering west by mid
afternoon. A slight chance of showers by mid afternoon. Waves
subsiding to 1 to 3 feet.
.MONDAY NIGHT...Northwest winds 15 to 25 knots becoming north
20 to 30 knots after midnight. Waves building to 4 to 7 feet
occasionally to 9 feet.
.TUESDAY...North gales to 35 knots diminishing to 20 to 30 knots
by mid afternoon. Waves building to 6 to 9 feet occasionally to
11 feet, then subsiding to 4 to 7 feet occasionally to 9 feet.
.TUESDAY NIGHT...Northwest winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to calm to 2 feet.
.WEDNESDAY...East winds 10 to 20 knots veering southeast. A
chance of rain showers. Waves calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots becoming east 20 to
30 knots. A chance of rain showers. Waves building to 5 to 8 feet
occasionally to 10 feet.

$$

LSZ263-220400-
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-
352 PM EDT Sat Oct 21 2017

.LATE THIS AFTERNOON...South winds 10 to 20 knots. Scattered
showers and isolated thunderstorms. Waves 1 to 3 feet.
.TONIGHT...South winds 10 to 20 knots. A chance of showers and a
slight chance of thunderstorms. Waves building to 2 to 4 feet.
.SUNDAY...Southwest winds 15 to 25 knots veering west in the
afternoon, then backing southwest late. A chance of showers
through early afternoon. Waves building to 3 to 6 feet
occasionally to 8 feet.
.SUNDAY NIGHT...Southwest winds 15 to 25 knots. Waves subsiding
to 2 to 4 feet, then building to 3 to 5 feet occasionally to
7 feet.
.MONDAY...South winds 15 to 25 knots becoming west 10 to 20 knots
by mid afternoon. Waves subsiding to 2 to 4 feet.
.MONDAY NIGHT...Northwest winds 15 to 25 knots becoming north
20 to 30 knots after midnight. A chance of showers. Waves
subsiding to 1 to 3 feet, then building to 4 to 7 feet
occasionally to 9 feet.
.TUESDAY...North gales to 40 knots. A chance of rain showers.
Waves building to 8 to 11 feet occasionally to 14 feet, then
subsiding to 6 to 9 feet occasionally to 11 feet.
.TUESDAY NIGHT...North winds 15 to 25 knots diminishing to 5 to
15 knots after midnight. Waves subsiding to 1 to 3 feet.
.WEDNESDAY...North winds 5 to 15 knots veering southeast. Waves
subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots becoming east 20 to
30 knots. Rain showers likely. Waves building to 4 to 7 feet
occasionally to 9 feet.

$$

LSZ264-220400-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
352 PM EDT Sat Oct 21 2017

.LATE THIS AFTERNOON...Southeast winds 15 to 25 knots. Scattered
showers and isolated thunderstorms. Waves 3 to 6 feet
occasionally to 8 feet.
.TONIGHT...South winds 15 to 25 knots. A chance of showers and a
slight chance of thunderstorms after midnight. Waves 3 to 6 feet
occasionally to 8 feet.
.SUNDAY...Southwest winds 15 to 25 knots veering west late.
Showers likely through early afternoon, then a slight chance of
showers and thunderstorms by mid afternoon. Waves subsiding to
3 to 5 feet occasionally to 7 feet, then building to 4 to 7 feet
occasionally to 9 feet.
.SUNDAY NIGHT...Southwest winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. Waves subsiding to 2 to 4 feet,
then building to 3 to 5 feet occasionally to 7 feet.
.MONDAY...South winds 10 to 20 knots veering southwest by mid
afternoon. Waves subsiding to 1 to 3 feet.
.MONDAY NIGHT...Northwest winds 10 to 20 knots becoming north
20 to 30 knots after midnight. A chance of showers. Waves
building to 4 to 7 feet occasionally to 9 feet.
.TUESDAY...North gales to 40 knots. A chance of showers through
early afternoon, then showers likely by mid afternoon. Waves
building to 10 to 14 feet occasionally to 18 feet.
.TUESDAY NIGHT...North winds 20 to 30 knots diminishing to 10 to
20 knots after midnight. A chance of rain showers. Waves
subsiding to 2 to 4 feet.
.WEDNESDAY...Northeast winds 5 to 15 knots veering southeast.
Waves subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 15 to 25 knots becoming east 20 to
30 knots. A chance of rain showers, then rain showers likely.
Waves building to 5 to 8 feet occasionally to 10 feet.

$$

LSZ265-220400-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
352 PM EDT Sat Oct 21 2017

.LATE THIS AFTERNOON...Southeast winds 15 to 25 knots. Waves 3 to
5 feet occasionally to 7 feet.
.TONIGHT...South winds 15 to 25 knots backing southeast after
midnight, then veering south late. A chance of showers and a
slight chance of thunderstorms after midnight. Waves subsiding to
2 to 4 feet.
.SUNDAY...South winds 20 to 30 knots becoming west 15 to 25 knots
in the afternoon, then diminishing to 10 to 20 knots late.
Showers and a slight chance of thunderstorms through mid afternoon.
Waves subsiding to 1 to 3 feet.
.SUNDAY NIGHT...Southwest winds 10 to 20 knots. Waves subsiding
to calm to 2 feet, then building to 1 to 3 feet.
.MONDAY...South winds 10 to 20 knots veering southwest by mid
afternoon. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...Northwest winds 10 to 20 knots becoming north
20 to 30 knots after midnight. Showers likely after midnight.
Waves building to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...North gales to 40 knots. Showers. Waves building to
12 to 17 feet occasionally to 21 feet, then subsiding to 11 to
15 feet occasionally to 19 feet.
.TUESDAY NIGHT...North gales to 35 knots diminishing to 15 to
25 knots after midnight. A chance of rain showers. Waves
subsiding to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...North winds 10 to 20 knots veering southeast. Waves
subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 15 to 25 knots increasing to 20 to
30 knots. A chance of rain showers, then rain showers likely.
Waves building to 4 to 7 feet occasionally to 9 feet.

$$

LSZ266-220400-
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-
352 PM EDT Sat Oct 21 2017

.LATE THIS AFTERNOON...South winds 20 to 30 knots. Waves 3 to
6 feet occasionally to 8 feet.
.TONIGHT...South winds 20 to 30 knots. A slight chance of showers
and thunderstorms after midnight. Waves 3 to 6 feet occasionally
to 8 feet.
.SUNDAY...South winds 20 to 30 knots becoming west 15 to 25 knots
in the afternoon. Showers likely and a slight chance of
thunderstorms. Waves 3 to 6 feet occasionally to 8 feet.
.SUNDAY NIGHT...Southwest winds 15 to 25 knots diminishing to
10 to 20 knots after midnight. A slight chance of showers through
midnight. Waves subsiding to 2 to 4 feet.
.MONDAY...South winds 10 to 20 knots. A slight chance of showers
by mid afternoon. Waves subsiding to 1 to 3 feet.
.MONDAY NIGHT...Northwest winds 10 to 20 knots becoming north
20 to 30 knots after midnight. Showers likely after midnight.
Waves building to 3 to 6 feet occasionally to 8 feet.
.TUESDAY...North gales to 40 knots. Showers. Waves building to
12 to 17 feet occasionally to 21 feet.
.TUESDAY NIGHT...North gales to 35 knots diminishing to 15 to
25 knots after midnight. A chance of rain showers. Waves
subsiding to 3 to 6 feet occasionally to 8 feet.
.WEDNESDAY...North winds 10 to 20 knots veering east. Waves
subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 15 to 25 knots increasing to 20 to
30 knots. Rain showers likely. Waves building to 4 to 7 feet
occasionally to 9 feet.

$$

LSZ267-220400-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
352 PM EDT Sat Oct 21 2017

.LATE THIS AFTERNOON...South winds 20 to 30 knots. Waves 2 to
4 feet building to 3 to 5 feet occasionally to 7 feet.
.TONIGHT...South winds 20 to 30 knots backing southeast late.
Waves subsiding to 2 to 4 feet, then building to 3 to 5 feet
occasionally to 7 feet.
.SUNDAY...South winds 20 to 30 knots becoming west 10 to 20 knots
late. A chance of showers and thunderstorms through mid afternoon.
Waves building to 3 to 6 feet occasionally to 8 feet, then
subsiding to 1 to 3 feet.
.SUNDAY NIGHT...West winds 10 to 20 knots becoming southwest 5 to
15 knots after midnight. A chance of showers. Waves subsiding to
calm to 2 feet.
.MONDAY...South winds 10 to 20 knots. A slight chance of showers
by mid afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...North winds 10 to 20 knots increasing to 15 to
25 knots after midnight. A chance of showers through midnight,
then showers likely after midnight. Waves building to 2 to
4 feet.
.TUESDAY...North gales to 35 knots. Showers. Waves building to
10 to 14 feet occasionally to 18 feet.
.TUESDAY NIGHT...North winds 20 to 30 knots. Rain showers likely
through midnight, then a chance of rain showers after midnight.
Waves subsiding to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...North winds 15 to 25 knots becoming northeast 10 to
20 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 10 to 20 knots increasing to 20 to
30 knots. Rain showers likely. Waves building to 3 to 6 feet
occasionally to 8 feet.

$$

LSZ261-220400-
MAFOR 2121/
Superior West 13420 11436 11536 13530. Scattered showers through
Sunday morning. Waves 1 to 4 feet building to 3 to 5 feet Sunday.

Superior North Central 14330 11330 11436 11536 11540. Scattered
showers through Sunday afternoon. Waves 3 to 6 feet.

Superior South Central 11330 12430 11330 11440 11446 11536 11626.
Chance of showers through late Sunday. Waves 3 to 6 feet
subsiding to 1 to 2 feet Sunday.

Superior East 11330 12430 11330 11340 11440 11446 11536. Chance
of showers late Sunday morning. Waves 3 to 6 feet.

$$

Borchardt

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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