Great Lakes Forecast
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142
FZUS63 KMQT 221959
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
359 PM EDT Tue May 22 2018

For waters beyond 5 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 weak low pressure trough of 30.0 inches will drop
south across Lake Superior tonight and Wednesday morning. As the
trough dissipates Wednesday, high pressure of 30.2 inches will
build over the Great Lakes region. The high will drift toward the
Mid-Atlantic States on Thursday as one low pressure trough of 29.7
inches drops across far northern Ontario and a second trough of
29.6 inches emerges over the western Canadian Plains. The plains
trough will approach the western Great Lakes on Friday, then
weaken over the area on Saturday to 29.8 inches. This disorganized
troughing will remain over the Upper Great Lakes Sunday.

LSZ162-230400-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
359 PM EDT Tue May 22 2018 /259 PM CDT Tue May 22 2018/

.LATE THIS AFTERNOON...Southwest winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...Southwest winds less than 10 knots backing east in
the afternoon, then increasing to 5 to 15 knots late. Waves calm
to 2 feet.
.WEDNESDAY NIGHT...East winds 5 to 15 knots becoming northeast
less than 10 knots after midnight, then veering east late. A
slight chance of showers and thunderstorms after midnight. Waves
calm to 2 feet.
.THURSDAY...East winds less than 10 knots. A chance of showers
and thunderstorms. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 5 to 15 knots veering southwest
after midnight. A chance of showers and thunderstorms. Waves calm
to 2 feet.
.FRIDAY...Southwest winds 5 to 15 knots. A chance of showers and
thunderstorms. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots backing east after
midnight. A chance of showers and thunderstorms. Waves calm to
2 feet.
.SATURDAY...Northeast winds 5 to 15 knots. Waves calm to 2 feet.
.SUNDAY...East winds less than 10 knots backing northeast. Waves
calm to 2 feet.

$$

LSZ263-230400-
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-
359 PM EDT Tue May 22 2018

.LATE THIS AFTERNOON...Southwest winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...Southwest winds 5 to 15 knots becoming north less
than 10 knots in the afternoon, then becoming northeast 5 to
15 knots late. Waves calm to 2 feet.
.WEDNESDAY NIGHT...East winds less than 10 knots. Waves calm to
2 feet.
.THURSDAY...Southeast winds less than 10 knots becoming east 5 to
15 knots by mid afternoon. A slight chance of showers and
thunderstorms. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 5 to 15 knots veering southwest
after midnight. A chance of showers and thunderstorms. Waves calm
to 2 feet.
.FRIDAY...Southwest winds 5 to 15 knots. A chance of showers and
thunderstorms. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots backing east after
midnight. A chance of showers and thunderstorms. Waves calm to
2 feet.
.SATURDAY...Northeast winds 5 to 15 knots. A chance of showers
and thunderstorms. Waves calm to 2 feet.
.SUNDAY...Northeast winds 5 to 15 knots becoming east less than
10 knots. A chance of showers and thunderstorms. Waves calm to
2 feet.

$$

LSZ264-230400-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
359 PM EDT Tue May 22 2018

.LATE THIS AFTERNOON...Southwest winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...Southwest winds 5 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...Northeast winds 5 to 15 knots veering east in the
afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to
2 feet.
.THURSDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. A slight chance of showers and thunderstorms by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...Southeast winds 10 to 20 knots veering
southwest after midnight. A chance of showers and thunderstorms.
Waves calm to 2 feet.
.FRIDAY...Southwest winds 10 to 20 knots backing southeast by mid
afternoon. A chance of showers and thunderstorms. Waves calm to
2 feet.
.FRIDAY NIGHT...Southeast winds 5 to 15 knots backing east after
midnight. A chance of showers and thunderstorms. Waves calm to
2 feet.
.SATURDAY...East winds 5 to 15 knots increasing to 10 to
20 knots. A chance of showers and thunderstorms. Waves calm to
2 feet.
.SUNDAY...East winds 5 to 15 knots. A chance of showers and
thunderstorms. Waves calm to 2 feet.

$$

LSZ265-230400-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
359 PM EDT Tue May 22 2018

.LATE THIS AFTERNOON...Southeast winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...South winds 5 to 15 knots veering southwest after
midnight. Waves calm to 2 feet.
.WEDNESDAY...South winds 5 to 15 knots backing east in the
afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south
late. Waves calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. A slight chance of showers and thunderstorms by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 5 to 15 knots becoming southwest
10 to 20 knots after midnight. A chance of showers and
thunderstorms. Waves calm to 2 feet.
.FRIDAY...Southwest winds 5 to 15 knots backing south by mid
afternoon. A chance of showers and thunderstorms through early
afternoon, then showers and thunderstorms likely by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 5 to 15 knots. A chance of showers
and thunderstorms. Waves calm to 2 feet.
.SATURDAY...North winds 5 to 15 knots veering east. A chance of
showers and thunderstorms. Waves calm to 2 feet.
.SUNDAY...East winds 10 to 20 knots diminishing to 5 to 15 knots.
A chance of showers and thunderstorms. Waves calm to 2 feet.

$$

LSZ266-230400-
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-
359 PM EDT Tue May 22 2018

.LATE THIS AFTERNOON...Southwest winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...South winds 5 to 15 knots. Waves calm to 2 feet.
.WEDNESDAY...Southeast winds 5 to 15 knots backing east in the
afternoon. Waves calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south
after midnight. Waves calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. A slight chance of showers and thunderstorms by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 10 to 20 knots veering southwest
after midnight. A chance of showers and thunderstorms. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.
.FRIDAY...South winds 10 to 20 knots diminishing to 5 to 15 knots
by mid afternoon. A chance of showers and thunderstorms through
early afternoon, then showers and thunderstorms likely by mid
afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...Southeast winds 10 to 20 knots becoming south
5 to 15 knots after midnight. A chance of showers and
thunderstorms. Waves calm to 2 feet.
.SATURDAY...East winds 5 to 15 knots. A chance of showers and
thunderstorms. Waves calm to 2 feet.
.SUNDAY...Southeast winds 5 to 15 knots. A chance of showers and
thunderstorms. Waves calm to 2 feet.

$$

LSZ267-230400-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
359 PM EDT Tue May 22 2018

.LATE THIS AFTERNOON...Northwest winds 5 to 15 knots. Waves calm
to 2 feet.
.TONIGHT...West winds 5 to 15 knots backing south late. Patchy
fog after midnight. Waves calm to 2 feet.
.WEDNESDAY...East winds 5 to 15 knots backing northwest late.
Waves calm to 2 feet.
.WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south
late. Waves calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.THURSDAY NIGHT...South winds 10 to 20 knots veering southwest
after midnight. A chance of showers and thunderstorms. Waves
building to 1 to 3 feet, then subsiding to calm to 2 feet.
.FRIDAY...South winds 10 to 20 knots. A chance of showers and
thunderstorms through early afternoon, then showers and
thunderstorms likely by mid afternoon. Waves calm to 2 feet.
.FRIDAY NIGHT...South winds 10 to 20 knots backing southeast
after midnight. Showers and thunderstorms likely through
midnight, then a chance of showers and thunderstorms after
midnight. Waves calm to 2 feet.
.SATURDAY...Southeast winds 10 to 20 knots. A chance of showers
and thunderstorms. Waves calm to 2 feet.
.SUNDAY...East winds 10 to 20 knots veering southeast. A chance
of showers and thunderstorms. Waves calm to 2 feet.

$$

LSZ261-230400-
MAFOR 2221/
Superior West 15500 11500 11200. Waves 1 foot or less.

Superior North Central 12510 13500 11400 11100 11200. Waves 2
feet or less.

Superior South Central 12300 11400 12500 11400 12200. Waves 1
foot or less.

Superior East 12600 12500 11300 12200 11300. Patchy fog
overnight. Waves 1 foot or less.

$$

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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