Great Lakes Forecast
Issued by NWS

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496
FZUS63 KMQT 221957
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
357 PM EDT Sat Jun 22 2024

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 29.7 inch low pressure over central Iowa tonight will
track northeast to near the Straits by Sunday morning as it deepens
to near 29.5 inches. Through the day Sunday, the low will continue
eastward into Quebec while strengthening to 29.3 inches while 29.8
inch ridging builds into the Upper Great Lakes from the west. The
high shifts southeast into the Appalachians Tuesday while building
to 30.0 inches. Monday night, a 29.2 inch low will track east
through Manitoba, spinning across northern Ontario into James Bay
Tuesday. This low will enable a 29.5 inch trough to sweep across
Lake Superior Tuesday. 29.9 inch high pressure from the High Plains
then extends into the Upper Great Lakes Wednesday. This high
builds to 30.0 inches on Thursday morning.

LSZ162-230400-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
357 PM EDT Sat Jun 22 2024 /257 PM CDT Sat Jun 22 2024/

.LATE THIS AFTERNOON...Northeast winds 10 to 20 knots. A chance
of showers and a slight chance of thunderstorms. Waves 2 to
4 feet.
.TONIGHT...Northeast winds 5 to 15 knots backing northwest after
midnight, then backing west late. A slight chance of
thunderstorms through midnight. A chance of showers. Patchy fog
after midnight. Waves subsiding to calm to 2 feet.
.SUNDAY...West winds 5 to 15 knots backing southwest late. A
slight chance of showers. A slight chance of thunderstorms by mid
afternoon. Waves calm to 2 feet.
.SUNDAY NIGHT...West winds 5 to 15 knots backing southwest late.
Waves calm to 2 feet.
.MONDAY...South winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...East winds 10 to 20 knots veering southwest after
midnight. Showers likely through midnight. A chance of
thunderstorms. A chance of showers after midnight. Waves calm to
2 feet.
.TUESDAY...Southwest winds 10 to 20 knots becoming west 15 to
25 knots by mid afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet, then subsiding to 2 to 4 feet.
.TUESDAY NIGHT...West winds 10 to 20 knots veering northwest
after midnight. Waves subsiding to calm to 2 feet.
.WEDNESDAY...South winds 10 to 20 knots diminishing to 5 to
15 knots. Waves calm to 2 feet.
.THURSDAY...East winds 10 to 20 knots. A chance of showers. 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-
357 PM EDT Sat Jun 22 2024

.LATE THIS AFTERNOON...Northeast winds 5 to 15 knots. A chance of
showers and a slight chance of thunderstorms. Waves 1 to 3 feet.
.TONIGHT...Northeast winds 5 to 15 knots backing northwest after
midnight, then backing west late. A slight chance of
thunderstorms through midnight. A chance of showers. Waves
subsiding to calm to 2 feet.
.SUNDAY...West winds 5 to 15 knots. A slight chance of showers.
Waves calm to 2 feet.
.SUNDAY NIGHT...West winds less than 10 knots backing southwest
after midnight. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing east by mid
afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 10 to 20 knots veering southwest
after midnight. Showers likely and a chance of thunderstorms.
Waves building to 2 to 4 feet.
.TUESDAY...Southwest winds 15 to 25 knots veering west by mid
afternoon. Waves building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY NIGHT...West winds 10 to 20 knots becoming north 5 to
15 knots after midnight. Waves subsiding to 1 to 3 feet.
.WEDNESDAY...North winds 5 to 15 knots veering south. Waves
subsiding to calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots backing southeast. A chance
of showers. 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-
357 PM EDT Sat Jun 22 2024

.LATE THIS AFTERNOON...Northeast winds 5 to 15 knots. A slight
chance of showers. Waves calm to 2 feet.
.TONIGHT...North winds 5 to 15 knots backing west after midnight.
A slight chance of showers. Waves calm to 2 feet.
.SUNDAY...West winds 5 to 15 knots veering northwest in the
afternoon. A chance of showers. Waves building to 1 to 3 feet,
then subsiding to calm to 2 feet.
.SUNDAY NIGHT...West winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots backing south by mid
afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 10 to 20 knots. A chance of showers
through midnight. A chance of thunderstorms. Showers likely after
midnight. Waves building to 2 to 4 feet.
.TUESDAY...Southwest winds 10 to 20 knots becoming west 15 to
25 knots by mid afternoon. Waves building to 3 to 5 feet
occasionally to 7 feet.
.TUESDAY NIGHT...West winds 10 to 20 knots veering north after
midnight. Waves subsiding to 2 to 4 feet.
.WEDNESDAY...North winds 5 to 15 knots backing southwest. Waves
subsiding to calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots backing southeast. A chance
of showers. Waves calm to 2 feet.

$$

LSZ265-230400-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
357 PM EDT Sat Jun 22 2024

.LATE THIS AFTERNOON...Northeast winds 10 to 20 knots. A chance
of showers. Waves calm to 2 feet.
.TONIGHT...North winds 5 to 15 knots backing northwest after
midnight, then becoming west 10 to 20 knots late. A chance of
showers. Waves calm to 2 feet.
.SUNDAY...West winds 10 to 20 knots becoming northwest 15 to
25 knots in the afternoon, then diminishing to 10 to 20 knots
late. A slight chance of showers. Waves building to 1 to 3 feet,
then subsiding to calm to 2 feet.
.SUNDAY NIGHT...Northwest winds 5 to 15 knots backing west after
midnight. Waves calm to 2 feet.
.MONDAY...Southwest winds 5 to 15 knots becoming southeast 10 to
20 knots by mid afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 10 to 20 knots. A chance of showers
through midnight. A chance of thunderstorms. Showers likely after
midnight. Waves building to 1 to 3 feet, then subsiding to calm
to 2 feet.
.TUESDAY...West winds 15 to 25 knots. Waves calm to 2 feet.
.TUESDAY NIGHT...West winds 10 to 20 knots veering northwest
after midnight. Waves calm to 2 feet.
.WEDNESDAY...North winds 10 to 20 knots becoming west 5 to
15 knots. Waves calm to 2 feet.
.THURSDAY...Southeast winds 5 to 15 knots becoming south 10 to
20 knots. A chance of showers. 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-
357 PM EDT Sat Jun 22 2024

.LATE THIS AFTERNOON...Northeast winds 5 to 15 knots. A chance of
showers. Waves calm to 2 feet.
.TONIGHT...North winds 5 to 15 knots increasing to 10 to 20 knots
after midnight, then backing northwest late. Patchy fog through
midnight. A chance of showers. Waves building to 1 to 3 feet.
.SUNDAY...Northwest winds 10 to 20 knots. A slight chance of
showers. Waves building to 2 to 4 feet.
.SUNDAY NIGHT...Northwest winds 5 to 15 knots backing west late.
Waves subsiding to calm to 2 feet.
.MONDAY...West winds 5 to 15 knots backing southeast by mid
afternoon. Waves calm to 2 feet.
.MONDAY NIGHT...South winds 10 to 20 knots increasing to 15 to
25 knots after midnight. A chance of thunderstorms. Showers
likely after midnight. Waves building to 2 to 4 feet.
.TUESDAY...Southwest winds 15 to 25 knots becoming west 10 to
20 knots by mid afternoon. A chance of showers through early
afternoon. Waves building to 3 to 5 feet occasionally to 7 feet.
.TUESDAY NIGHT...West winds 10 to 20 knots veering northwest
after midnight. Waves subsiding to 2 to 4 feet.
.WEDNESDAY...Northwest winds 10 to 20 knots diminishing to 5 to
15 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...South winds 5 to 15 knots increasing to 10 to
20 knots. A chance of showers. 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-
357 PM EDT Sat Jun 22 2024

.LATE THIS AFTERNOON...East winds 10 to 20 knots. Showers likely.
Waves calm to 2 feet.
.TONIGHT...North winds 10 to 20 knots. Patchy fog. A chance of
showers. Waves building to 1 to 3 feet.
.SUNDAY...Northwest winds 10 to 20 knots. A slight chance of
showers. Waves 1 to 3 feet.
.SUNDAY NIGHT...Northwest winds 10 to 20 knots backing west late.
A slight chance of showers through midnight. Waves subsiding to
calm to 2 feet.
.MONDAY...West winds 5 to 15 knots backing east by mid afternoon.
Waves calm to 2 feet.
.MONDAY NIGHT...South winds 10 to 20 knots increasing to 15 to
25 knots after midnight. Showers likely and a chance of
thunderstorms after midnight. Waves building to 2 to 4 feet.
.TUESDAY...South winds 15 to 25 knots becoming west 10 to
20 knots by mid afternoon. A chance of showers and thunderstorms.
Waves subsiding to 1 to 3 feet.
.TUESDAY NIGHT...West winds 10 to 20 knots veering northwest
after midnight. Waves 1 to 3 feet.
.WEDNESDAY...Northwest winds 10 to 20 knots diminishing to 5 to
15 knots. Waves subsiding to calm to 2 feet.
.THURSDAY...Southwest winds 5 to 15 knots becoming south 10 to
20 knots. Waves calm to 2 feet.

$$

LSZ261-230400-
MAFOR 2221/
Superior West 11120 11110 11800 11700 13610 11600. A chance of
showers this evening. Waves 2 to 4 feet subsiding to 1 to 2 feet
tonight and Sunday.

Superior North Central 11100 11800 11700 11600 11610 12710 11720.
Waves 1 foot or less tonight. Waves 1 to 3 feet Sunday.

Superior South Central 11110 12810 12710 11620 12720. A chance of
showers tonight. Waves 1 to 3 feet.

Superior East 11116 11810 12820 11810 12710 11720. Waves 1 to 3
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