Great Lakes Forecast
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

251
FZUS63 KMQT 192003
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
403 PM EDT Tue Sep 19 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...High pressure of 30.1 inches will drift to southern
Quebec through Tuesday, then remain nearly stationary through
Thursday. A 29.5 inch trough developing over the northern High
Plains will weaken to 29.8 inches as it sweeps eastward, passing
across Lake Superior Wednesday afternoon and evening. Lake Superior
will then remain situated between a 30.1 inch ridge across the Lower
Great Lakes and a 29.8 inch trough over the Upper Mississippi Valley
Thursday through Saturday.

LSZ162-200415-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
403 PM EDT Tue Sep 19 2017 /303 PM CDT Tue Sep 19 2017/

.LATE THIS AFTERNOON...East winds 10 to 20 knots. Waves 1 to
3 feet building to 2 to 4 feet.
.TONIGHT...East winds 15 to 25 knots veering southeast after
midnight. Scattered showers and isolated thunderstorms after
midnight. Waves 2 to 4 feet.
.WEDNESDAY...Southeast winds 10 to 20 knots veering southwest
late. Scattered showers and thunderstorms. Waves building to 3 to
5 feet occasionally to 7 feet, then subsiding to 1 to 3 feet.
.WEDNESDAY NIGHT...West winds 5 to 15 knots backing southwest
late. Waves subsiding to calm to 2 feet.
.THURSDAY...Southeast winds 5 to 15 knots becoming east 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...East winds 5 to 15 knots. A chance of showers.
Waves calm to 2 feet.
.FRIDAY...East winds 5 to 15 knots. A chance of showers. Waves
calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. A chance of showers and thunderstorms. Waves
building to 1 to 3 feet.
.SATURDAY...South winds 10 to 20 knots becoming northeast 5 to
15 knots. A chance of showers. A chance of thunderstorms. Showers
likely. Waves subsiding to calm to 2 feet.
.SUNDAY...Northeast winds 10 to 20 knots veering east. A chance
of showers and thunderstorms. Waves building to 1 to 3 feet, then
subsiding to calm to 2 feet.

$$

LSZ263-200415-
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-
403 PM EDT Tue Sep 19 2017

.LATE THIS AFTERNOON...East winds 10 to 20 knots. Waves calm to
2 feet building to 1 to 3 feet.
.TONIGHT...East winds 10 to 20 knots veering southeast after
midnight. Scattered showers after midnight. Waves building to
2 to 4 feet.
.WEDNESDAY...Southeast winds 15 to 25 knots veering south in the
afternoon, then becoming southwest 10 to 20 knots late. Scattered
showers and thunderstorms. Waves building to 4 to 7 feet
occasionally to 9 feet, then subsiding to 2 to 4 feet.
.WEDNESDAY NIGHT...West winds 5 to 15 knots becoming south less
than 10 knots late. Waves subsiding to calm to 2 feet.
.THURSDAY...Southeast winds less than 10 knots becoming east 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. A chance of showers. Waves calm to 2 feet.
.FRIDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots increasing to 10 to
20 knots after midnight. A chance of showers and thunderstorms.
Waves building to 1 to 3 feet.
.SATURDAY...South winds 10 to 20 knots becoming north 5 to
15 knots. A chance of showers and thunderstorms. Waves building
to 2 to 4 feet, then subsiding to calm to 2 feet.
.SUNDAY...Northeast winds 5 to 15 knots. A chance of showers and
thunderstorms. Waves building to 1 to 3 feet, then subsiding to
calm to 2 feet.

$$

LSZ264-200415-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
403 PM EDT Tue Sep 19 2017

.LATE THIS AFTERNOON...East winds 5 to 15 knots. Waves calm to
2 feet building to 1 to 3 feet.
.TONIGHT...Southeast winds 10 to 20 knots. Isolated showers after
midnight. Waves building to 3 to 5 feet occasionally to 7 feet.
.WEDNESDAY...Southeast winds 15 to 25 knots increasing to 20 to
30 knots in the afternoon, then becoming south 15 to 25 knots
late. Patchy fog through early afternoon. Scattered showers and
thunderstorms. Waves building to 4 to 8 feet occasionally to
10 feet.
.WEDNESDAY NIGHT...West winds 5 to 15 knots diminishing to less
than 10 knots late. A slight chance of showers and thunderstorms
through midnight. Waves subsiding to calm to 2 feet.
.THURSDAY...Southeast winds less than 10 knots increasing to 5 to
15 knots by mid afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 5 to 15 knots. A chance of
showers after midnight. Waves building to 1 to 3 feet.
.FRIDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. A chance of showers. Waves subsiding to calm to
2 feet, then building to 1 to 3 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots. A chance of showers.
Waves building to 2 to 4 feet.
.SATURDAY...South winds 5 to 15 knots. A chance of showers and
thunderstorms. Waves subsiding to calm to 2 feet.
.SUNDAY...Northeast winds 5 to 15 knots. A chance of showers and
thunderstorms. Waves building to 1 to 3 feet.

$$

LSZ265-200415-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
403 PM EDT Tue Sep 19 2017

.LATE THIS AFTERNOON...East winds 10 to 20 knots. Waves 1 to
3 feet.
.TONIGHT...Southeast winds 10 to 20 knots increasing to 15 to
25 knots after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.WEDNESDAY...Southeast winds 15 to 25 knots veering south late.
Scattered showers and thunderstorms. Waves building to 3 to
6 feet occasionally to 8 feet.
.WEDNESDAY NIGHT...West winds 10 to 20 knots diminishing to 5 to
15 knots after midnight, then veering northwest late. A chance of
showers and thunderstorms through midnight. Waves subsiding to
calm to 2 feet.
.THURSDAY...East winds 5 to 15 knots. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. A chance of showers after midnight. Waves calm to
2 feet.
.FRIDAY...South winds 10 to 20 knots. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots veering southwest
after midnight. A chance of showers. Waves building to 1 to
3 feet.
.SATURDAY...South winds 10 to 20 knots. A chance of showers.
Waves subsiding to calm to 2 feet.
.SUNDAY...Northeast winds 10 to 20 knots. A chance of showers and
thunderstorms. Waves building to 1 to 3 feet.

$$

LSZ266-200415-
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-
403 PM EDT Tue Sep 19 2017

.LATE THIS AFTERNOON...East winds 10 to 20 knots. Waves calm to
2 feet building to 1 to 3 feet.
.TONIGHT...East winds 10 to 20 knots becoming southeast 15 to
25 knots after midnight. Waves building to 3 to 5 feet
occasionally to 7 feet.
.WEDNESDAY...Southeast winds 15 to 25 knots veering south late.
Patchy fog through early afternoon. Scattered showers. Scattered
thunderstorms by mid afternoon. Waves building to 4 to 8 feet
occasionally to 10 feet.
.WEDNESDAY NIGHT...South winds 10 to 20 knots becoming northwest
5 to 15 knots after midnight, then veering north late. A chance
of thunderstorms through midnight. A chance of showers. Waves
subsiding to calm to 2 feet.
.THURSDAY...North winds 5 to 15 knots veering east by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south
after midnight. A chance of showers after midnight. Waves
building to 1 to 3 feet.
.FRIDAY...South winds 10 to 20 knots. Waves 1 to 3 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots. A chance of showers.
Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet.
.SATURDAY...South winds 10 to 20 knots. A chance of showers and
thunderstorms. Waves subsiding to calm to 2 feet, then building
to 1 to 3 feet.
.SUNDAY...Southwest winds 5 to 15 knots becoming south 10 to
20 knots. A chance of showers and thunderstorms. Waves building
to 1 to 3 feet.

$$

LSZ267-200415-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
403 PM EDT Tue Sep 19 2017

.LATE THIS AFTERNOON...East winds 5 to 15 knots. Waves calm to
2 feet.
.TONIGHT...East winds 5 to 15 knots becoming southeast 10 to
20 knots after midnight, then increasing to 15 to 25 knots late.
Waves building to 1 to 3 feet.
.WEDNESDAY...Southeast winds 15 to 25 knots. Scattered showers
and isolated thunderstorms by mid afternoon. Waves building to
2 to 4 feet.
.WEDNESDAY NIGHT...South winds 10 to 20 knots becoming north 5 to
15 knots late. Showers likely through midnight. A chance of
thunderstorms. A chance of showers after midnight. Waves
subsiding to calm to 2 feet.
.THURSDAY...North winds 5 to 15 knots veering northeast by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 5 to 15 knots increasing to
10 to 20 knots after midnight. A chance of showers. Waves calm to
2 feet.
.FRIDAY...South winds 10 to 20 knots. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots. A chance of showers.
Waves calm to 2 feet.
.SATURDAY...South winds 10 to 20 knots. Waves building to 1 to
3 feet, then subsiding to calm to 2 feet.
.SUNDAY...Southwest winds 10 to 20 knots backing south. A chance
of showers and thunderstorms. Waves calm to 2 feet.

$$

LSZ261-200415-
MAFOR 1921/
Superior West 11220 11230 13330 11329 11420 11520. Scattered
showers late tonight through Wednesday. Scattered thunderstorms
on late Wednesday morning through Wednesday afternoon. Waves 2 to
5 feet.

Superior North Central 14320 11330 13340. Patchy fog Wednesday
afternoon. Scattered showers Wednesday morning...Then scattered
showers and thunderstorms on late Wednesday morning through
Wednesday evening. Waves 2 to 5 feet building to 5 to 8 feet
Wednesday.

Superior South Central 11220 13320 14330. Scattered showers and
thunderstorms late Wednesday afternoon through Wednesday evening.
Waves 2 to 5 feet.

Superior East 12210 14320 12330. Waves 1 to 5 feet.

$$

JSS

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.