Great Lakes Forecast
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
000
FZUS63 KMQT 170752
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
352 AM EDT Sun Sep 17 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...Low pressure of 29.9 inches over far southeast
Manitoba will lift across northern Ontario today, pushing an
associated cold front across Lake Superior. In its wake, high
pressure of 30.2 inches over the western Dakotas will move east,
reaching the Upper Great Lakes late tonight and Monday. As the
high shifts to southern Quebec by Tuesday afternoon, a 29.5 inch
trough will move out across the Northern Plains. This trough will
weaken to 29.8 inches as it sweeps east, passing across Lake
Superior Wednesday afternoon and evening. Another low pressure
trough of 29.7 inches will then emerge over the Plains States on
Thursday.

LSZ162-171600-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
352 AM EDT Sun Sep 17 2017 /252 AM CDT Sun Sep 17 2017/

.EARLY THIS MORNING...West winds 20 to 30 knots. Waves 2 to
4 feet building to 3 to 5 feet occasionally to 7 feet.
.TODAY...West winds 20 to 30 knots diminishing to 15 to 25 knots
late. Waves building to 4 to 7 feet occasionally to 9 feet, then
subsiding to 3 to 5 feet occasionally to 7 feet.
.TONIGHT...West winds 10 to 20 knots becoming southwest 5 to
15 knots late. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south in the
afternoon, then becoming southeast 10 to 20 knots late. A slight
chance of showers by mid afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to
2 feet.
.TUESDAY...Southeast winds 10 to 20 knots backing east by mid
afternoon. Waves building to 1 to 3 feet.
.TUESDAY NIGHT...East winds 10 to 20 knots becoming southeast
15 to 25 knots after midnight. A chance of showers. Waves
building to 2 to 4 feet, then subsiding to 1 to 3 feet.
.WEDNESDAY...South winds 10 to 20 knots veering west. A chance of
showers. Waves building to 2 to 4 feet, then subsiding to calm to
2 feet.
.THURSDAY...East winds 5 to 15 knots increasing to 10 to
20 knots. A chance of showers. Waves building to 1 to 3 feet,
then subsiding to calm to 2 feet.

$$

LSZ263-171600-
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 AM EDT Sun Sep 17 2017

.EARLY THIS MORNING...Southwest winds 20 to 30 knots. Isolated
showers and thunderstorms. Waves 1 to 3 feet building to 3 to
5 feet occasionally to 7 feet.
.TODAY...West winds 20 to 30 knots. Waves building to 5 to 9 feet
occasionally to 11 feet.
.TONIGHT...West winds 15 to 25 knots diminishing to 5 to 15 knots
after midnight. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south late. A
slight chance of showers by mid afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to
2 feet.
.TUESDAY...Southeast winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...East winds 5 to 15 knots becoming southeast
10 to 20 knots after midnight. A chance of showers after
midnight. Waves building to 1 to 3 feet.
.WEDNESDAY...Southeast winds 10 to 20 knots veering west. A
chance of showers. Waves building to 3 to 5 feet occasionally to
7 feet, then subsiding to calm to 2 feet.
.THURSDAY...East winds 5 to 15 knots veering southeast. A chance
of showers. Waves calm to 2 feet.

$$

LSZ264-171600-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
352 AM EDT Sun Sep 17 2017

.EARLY THIS MORNING...South winds 10 to 20 knots. Scattered
showers and thunderstorms. Waves 1 to 3 feet.
.TODAY...West winds 20 to 30 knots. Isolated showers in the
morning. Waves building to 5 to 9 feet occasionally to 11 feet.
.TONIGHT...West winds 15 to 25 knots diminishing to 5 to 15 knots
after midnight. Waves subsiding to 1 to 3 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south late. Waves
subsiding to calm to 2 feet.
.MONDAY NIGHT...South winds 5 to 15 knots backing southeast after
midnight. A slight chance of showers through midnight. Waves calm
to 2 feet.
.TUESDAY...Southeast winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...East winds 5 to 15 knots becoming southeast
10 to 20 knots after midnight. Waves building to 2 to 4 feet.
.WEDNESDAY...Southeast winds 15 to 25 knots veering west. A
chance of showers. Waves building to 3 to 6 feet occasionally to
8 feet, then subsiding to 1 to 3 feet.
.THURSDAY...East winds 5 to 15 knots veering southeast. A chance
of showers. Waves subsiding to calm to 2 feet.

$$

LSZ265-171600-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
352 AM EDT Sun Sep 17 2017

.EARLY THIS MORNING...South winds 10 to 20 knots. Numerous
showers and scattered thunderstorms. Waves 1 to 3 feet subsiding
to calm to 2 feet.
.TODAY...West winds 15 to 25 knots increasing to 20 to 30 knots
in the afternoon. Scattered showers and isolated thunderstorms in
the morning. Waves building to 3 to 6 feet occasionally to 8
feet.
.TONIGHT...West winds 15 to 25 knots diminishing to 5 to
15 knots. Waves subsiding to calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south in the
afternoon, then becoming southeast 10 to 20 knots late. A slight
chance of showers by mid afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...Southeast winds 10 to 20 knots. A chance of
showers through midnight. Waves calm to 2 feet.
.TUESDAY...Southeast winds 10 to 20 knots backing east by mid
afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...East winds 10 to 20 knots becoming southeast
15 to 25 knots after midnight. Waves building to 1 to 3 feet.
.WEDNESDAY...Southeast winds 15 to 25 knots becoming west 10 to
20 knots. A chance of showers. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to calm to 2 feet.
.THURSDAY...East winds 10 to 20 knots veering southeast. A chance
of showers. Waves calm to 2 feet.

$$

LSZ266-171600-
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 AM EDT Sun Sep 17 2017

.EARLY THIS MORNING...South winds 10 to 20 knots. Scattered
showers and thunderstorms. Waves 2 to 4 feet subsiding to 1 to
3 feet.
.TODAY...Southwest winds 20 to 30 knots veering west in the
afternoon. Scattered showers and isolated thunderstorms through
early afternoon. Waves building to 5 to 9 feet occasionally to
11 feet.
.TONIGHT...West winds 15 to 25 knots becoming northwest 10 to
20 knots after midnight, then diminishing to 5 to 15 knots late.
Waves subsiding to 2 to 4 feet.
.MONDAY...West winds 5 to 15 knots backing south in the
afternoon. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...Southeast winds 5 to 15 knots increasing to 10 to
20 knots after midnight. A chance of showers through midnight.
Waves calm to 2 feet.
.TUESDAY...East winds 10 to 20 knots. Waves calm to 2 feet.
.TUESDAY NIGHT...East winds 10 to 20 knots veering southeast
after midnight. Waves building to 2 to 4 feet.
.WEDNESDAY...Southeast winds 15 to 25 knots veering northwest. A
chance of showers. Waves building to 3 to 6 feet occasionally to
8 feet, then subsiding to 1 to 3 feet.
.THURSDAY...East winds 5 to 15 knots becoming south 10 to
20 knots. A chance of showers. Waves subsiding to calm to 2 feet.

$$

LSZ267-171600-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
352 AM EDT Sun Sep 17 2017

.EARLY THIS MORNING...South winds 15 to 25 knots. Scattered
showers and thunderstorms. Waves 2 to 4 feet subsiding to 1 to
3 feet.
.TODAY...South winds 10 to 20 knots becoming west 15 to 25 knots
in the afternoon, then becoming northwest 20 to 30 knots late.
Numerous showers and scattered thunderstorms through early
afternoon, then isolated showers by mid afternoon. Waves
subsiding to calm to 2 feet, then building to 4 to 7 feet
occasionally to 9 feet.
.TONIGHT...Northwest winds 15 to 25 knots diminishing to 10 to
20 knots after midnight. Waves subsiding to 2 to 4 feet.
.MONDAY...North winds 5 to 15 knots veering northeast in the
afternoon. Waves subsiding to calm to 2 feet.
.MONDAY NIGHT...East winds 5 to 15 knots increasing to 10 to
20 knots after midnight. A chance of showers. Waves calm to
2 feet.
.TUESDAY...East winds 10 to 20 knots diminishing to 5 to 15 knots
by mid afternoon. Waves calm to 2 feet.
.TUESDAY NIGHT...East winds 10 to 20 knots veering southeast
after midnight. Waves building to 1 to 3 feet.
.WEDNESDAY...Southeast winds 15 to 25 knots becoming south 10 to
20 knots. A chance of showers. Waves building to 2 to 4 feet,
then subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 5 to 15 knots increasing to 10 to
20 knots. Waves calm to 2 feet.

$$

LSZ261-171600-
MAFOR 1709/
Superior West 14640 11640 11630 12610. Waves 2 to 4 feet building
to 4 to 7 feet today. Waves 3 to 6 feet subsiding to 1 to 3 feet
tonight.

Superior North Central 11426 11540 13640 11630 11620 11610.
Scattered thunderstorms early this morning...then scattered
showers and thunderstorms through mid morning. Waves 1 to 3 feet
building to 6 to 9 feet today, then subsiding to 2 to 4 feet
tonight.

Superior South Central 11416 11530 13640 11630 11620 11710.
Scattered thunderstorms early this morning...Then scattered
showers and thunderstorms through mid morning. Scattered showers
late this morning. Waves 1 to 3 feet building to 3 to 6 feet
today, then subsiding to 1 to 3 feet tonight.

Superior East 11420 11426 11530 11630 12730 11720 11710.
Scattered showers and thunderstorms this morning. Waves 1 to 4
feet building to 4 to 7 feet today. Waves 5 to 8 feet subsiding
to 3 to 5 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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.