Great Lakes Forecast
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FZUS63 KMQT 121358
GLFLS

Open Lake Forecast for Lake Superior
National Weather Service Marquette MI
958 AM EDT Fri Apr 12 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 considerable pressure gradient has set up across
Lake Superior this morning. This pressure gradient holds across
the lake today as a 28.9 inch low currently centered over southern
Ontario, just east of Lake Huron, slowly lifts north toward
Quebec. By this evening, ridging at 30.0 inches builds across
western Lake Superior then shifts east across the entire lake
Saturday. Ridging shifts east Saturday night as a broad 29.7 inch
low pressure moves across the Upper Midwest. This low pressure
brushes the Great Lakes Sunday, centering over Lake Michigan early
Sunday morning before being absorbed by deeper low pressure east
of James Bay. A 30.0 inch ridge extending from northwest Ontario
follows in its wake Sunday afternoon into Monday, building to 30.2
inches Tuesday morning. During Tuesday, deep low pressure of 29.2
inches will lift northeast through the central Plains.

LSZ162-122200-
Lake Superior west of a line from Saxon Harbor WI to Grand
Portage MN beyond 5NM-
958 AM EDT Fri Apr 12 2024 /858 AM CDT Fri Apr 12 2024/

.REST OF TODAY...Northwest winds 15 to 25 knots. A slight chance
of rain showers through late morning. Waves 2 to 4 feet subsiding
to 1 to 3 feet.
.TONIGHT...Northwest winds 10 to 20 knots becoming west 5 to
15 knots late. Waves subsiding to calm to 2 feet.
.SATURDAY...West winds 5 to 15 knots backing south in the
afternoon, then backing east late. A slight chance of rain
showers by mid afternoon. Waves building to 1 to 3 feet.
.SATURDAY NIGHT...Northeast winds 10 to 20 knots. A chance of
rain showers. Waves building to 2 to 4 feet, then subsiding to
calm to 2 feet.
.SUNDAY...West winds 10 to 20 knots backing southwest by mid
afternoon. Waves calm to 2 feet.
.SUNDAY NIGHT...West winds 5 to 15 knots becoming northwest 10 to
20 knots after midnight. Waves calm to 2 feet.
.MONDAY...East winds 10 to 20 knots increasing to 20 to 30 knots.
A chance of rain showers. Waves building to 3 to 6 feet
occasionally to 8 feet.
.TUESDAY...Northeast gales to 35 knots. Rain showers. Waves
building to 6 to 9 feet occasionally to 11 feet, then subsiding
to 4 to 7 feet occasionally to 9 feet.

$$

LSZ263-122200-
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-
958 AM EDT Fri Apr 12 2024

.REST OF TODAY...North winds 20 to 30 knots becoming northwest
15 to 25 knots in the afternoon. A slight chance of rain showers
through late morning. Waves 3 to 5 feet occasionally to 7 feet
subsiding to 2 to 4 feet.
.TONIGHT...Northwest winds 10 to 20 knots. Waves subsiding to
1 to 3 feet.
.SATURDAY...West winds 5 to 15 knots backing southwest in the
afternoon, then backing east late. A slight chance of rain
showers by mid afternoon. Waves subsiding to calm to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots backing northeast
after midnight. A chance of rain showers. Waves calm to 2 feet.
.SUNDAY...North winds 5 to 15 knots backing southwest by mid
afternoon. Waves calm to 2 feet.
.SUNDAY NIGHT...Southwest winds 5 to 15 knots veering west after
midnight. Waves calm to 2 feet.
.MONDAY...East winds 5 to 15 knots increasing to 15 to 25 knots.
A chance of rain showers. Waves building to 3 to 5 feet
occasionally to 7 feet.
.TUESDAY...East gales to 35 knots. A chance of rain showers, then
rain showers. Waves building to 7 to 10 feet occasionally to
13 feet.

$$

LSZ264-122200-
Lake Superior from Upper Entrance to Portage Canal to Manitou
Island MI 5NM off shore to the US/Canadian Border-
958 AM EDT Fri Apr 12 2024

...GALE WARNING IN EFFECT UNTIL 5 PM EDT THIS AFTERNOON...

.REST OF TODAY...North winds 20 to 30 knots increasing to gales
to 35 knots by the afternoon, then becoming northwest 20 to 30
knots late. Waves 4 to 8 feet occasionally to 10 feet, then
subsiding to 3 to 6 feet occasionally to 8 feet.
.TONIGHT...Northwest winds 20 to 30 knots. Waves subsiding to
3 to 5 feet occasionally to 7 feet.
.SATURDAY...Northwest winds 10 to 20 knots becoming west 5 to
15 knots in the afternoon, then backing southwest late. A chance
of rain showers by mid afternoon. Waves subsiding to calm to
2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots. A chance of rain
showers. Waves calm to 2 feet.
.SUNDAY...North winds 5 to 15 knots backing west by mid
afternoon. Waves calm to 2 feet.
.SUNDAY NIGHT...West winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...West winds 5 to 15 knots becoming east 10 to 20 knots.
Waves building to 2 to 4 feet.
.TUESDAY...East gales to 35 knots. A chance of rain showers, then
rain showers. Waves building to 7 to 10 feet occasionally to
13 feet.

$$

LSZ265-122200-
Lake Superior West of Line from Manitou Island to Marquette MI
Beyond 5NM from shore-
958 AM EDT Fri Apr 12 2024

...GALE WARNING IN EFFECT UNTIL 7 PM EDT THIS EVENING...

.REST OF TODAY...North gales to 35 knots backing northwest in the
afternoon. A slight chance of rain showers through late morning.
Waves 5 to 9 feet occasionally to 11 feet, then subsiding to 4 to
7 feet occasionally to 9 feet.
.TONIGHT...Northwest winds 20 to 30 knots. Waves subsiding to
3 to 5 feet occasionally to 7 feet.
.SATURDAY...Northwest winds 10 to 20 knots becoming west 5 to
15 knots in the afternoon, then backing east late. A slight
chance of rain showers by mid afternoon. Waves subsiding to calm
to 2 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots. A chance of rain
showers. Waves calm to 2 feet.
.SUNDAY...North winds 5 to 15 knots backing northwest by mid
afternoon. Waves calm to 2 feet.
.SUNDAY NIGHT...West winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...East winds 5 to 15 knots increasing to 10 to 20 knots.
A chance of rain showers. Waves building to 2 to 4 feet.
.TUESDAY...East gales to 35 knots. Rain showers. Waves building
to 6 to 9 feet occasionally to 11 feet, then subsiding to 4 to
7 feet occasionally to 9 feet.

$$

LSZ266-122200-
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-
958 AM EDT Fri Apr 12 2024

...GALE WARNING IN EFFECT THROUGH LATE TONIGHT...

.REST OF TODAY...North gales to 40 knots becoming northwest gales
to 45 knots in the afternoon, then diminishing to gales to 40
knots late. A chance of rain showers through late morning. Waves 7
to 10 feet occasionally to 13 feet building to 10 to 14 feet
occasionally to 18 feet.
.TONIGHT...Northwest gales to 40 knots. Waves subsiding to 6 to
9 feet occasionally to 11 feet.
.SATURDAY...Northwest winds 20 to 30 knots diminishing to 10 to
20 knots in the afternoon, then becoming west 5 to 15 knots late.
A slight chance of rain showers by mid afternoon. Waves subsiding
to 1 to 3 feet.
.SATURDAY NIGHT...East winds 5 to 15 knots. A chance of rain
showers. Waves subsiding to calm to 2 feet.
.SUNDAY...North winds 5 to 15 knots backing northwest by mid
afternoon. Waves calm to 2 feet.
.SUNDAY NIGHT...West winds 5 to 15 knots. Waves calm to 2 feet.
.MONDAY...West winds 5 to 15 knots becoming east 10 to 20 knots.
Waves building to 2 to 4 feet.
.TUESDAY...East gales to 35 knots. A chance of rain showers, then
rain showers. Waves building to 6 to 10 feet occasionally to
13 feet.

$$

LSZ267-122200-
Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off
shore to the US/Canadian border-
958 AM EDT Fri Apr 12 2024

...GALE WARNING IN EFFECT THROUGH SATURDAY MORNING...

.REST OF TODAY...North gales to 40 knots becoming northwest gales
to 45 knots in the afternoon. Rain showers likely through late
morning, then a slight chance of rain showers through mid
afternoon. Waves 6 to 9 feet occasionally to 11 feet building to
10 to 14 feet occasionally to 18 feet.
.TONIGHT...Northwest gales to 45 knots. Waves subsiding to 7 to
10 feet occasionally to 13 feet.
.SATURDAY...Northwest gales to 35 knots diminishing to 20 to
30 knots in the afternoon, then becoming west 10 to 20 knots
late. A slight chance of rain showers by mid afternoon. Waves
subsiding to 2 to 4 feet.
.SATURDAY NIGHT...Southeast winds 5 to 15 knots becoming east
10 to 20 knots after midnight. A chance of rain showers. Waves
subsiding to calm to 2 feet.
.SUNDAY...Northeast winds 10 to 20 knots backing northwest by mid
afternoon. Waves building to 1 to 3 feet.
.SUNDAY NIGHT...West winds 10 to 20 knots. Waves subsiding to
calm to 2 feet.
.MONDAY...West winds 10 to 20 knots backing east. Waves building
to 1 to 3 feet.
.TUESDAY...East winds 20 to 30 knots becoming southeast gales to
35 knots. A chance of rain showers, then rain showers. Waves
building to 4 to 7 feet occasionally to 9 feet, then subsiding to
3 to 6 feet occasionally to 8 feet.

$$
LSZ261-122200-
MAFOR 1215/
Superior West 14720 13710 11600. Waves 1 to 3 feet this afternoon
and tonight. Waves 2 feet or less Saturday morning.

Superior North Central...GALE WARNING IN EFFECT...11850 11750
14740 11740 11730. Waves 5 to 8 feet this afternoon. Waves 3 to 6
feet tonight and Saturday morning.

Superior South Central...GALE WARNING IN EFFECT...15750 12740. A
chance of rain showers through this afternoon. Waves 7 to 10 feet
this afternoon subsiding to 4 to 8 feet tonight and Saturday
morning.

Superior East...GALE WARNING IN EFFECT...15750 11750 11740. A
chance of rain showers through this afternoon. Waves 7 to 10 feet
building to 9 to 12 feet this afternoon. Waves then subside to 6
to 9 feet by Saturday morning.

$$

Jablonski

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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