367
FZUS63 KMKX 030753
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
253 AM CDT Wed Sep 3 2025

FOR WATERS BEYOND FIVE NAUTICAL MILES OF SHORE ON Lake Michigan.

Waves are provided as a range of significant wave heights, which
is the average of the highest 1/3 of the wave, along with the
average height of the highest 10% of the waves which will
occasionally be encountered.

.SYNOPSIS...

29.6 inch low pressure is centered over Lake Superior this
morning, resulting in breezy southwest winds across the open
waters of Lake Michigan. Said low will progress toward the
Ontario-Quebec border today, deepening to near 29.4 inches in the
process. Breezy southwest winds will thus continue into this
morning, with gusts in the 20-25 knot range anticipated across all
of Lake Michigan. A few gusts could briefly gale-force,
particularly across the northern third of the waters. Winds will
quickly shift out of the northwest this afternoon and evening as a
cold front moves across the waters. Additional gusts in the 20-25
knot range are anticipated during and immediately following the
frontal passage. Winds will taper tonight as 29.9 inch high
pressure settles into the northern Great Plains.

High pressure will progress east into the western Ohio River Valley
on Thursday, allowing winds to turn out of the southwest by the
early afternoon hours. Winds will quickly become gusty Thursday
evening into predawn Friday morning as a second area of 29.5 inch
low pressure approaches Lake Michigan from the northern Great
Plains. The low will cross the waters near/just after daybreak
Friday morning, resulting in a west-northwest wind shift from late
morning into the early afternoon. Gale force gusts are expected
over at least the southern half of Lake Michigan as the low
approaches and crosses early Friday morning. Headlines will become
necessary in subsequent forecasts. Gusts will begin to taper
Friday afternoon and evening as the aforementioned low moves into
Quebec.

Showers and isolated thunderstorms are likely this morning and
afternoon as a cold front moves south across Lake Michigan. Severe
weather is not expected, though a few storms could produce brief
gusty winds. A few waterspouts are possible in embedded
thunderstorms, particularly across the northern half of Lake
Michigan. Scattered lake effect showers will remain possible through
the day on Thursday over far northern Lake Michigan. Additional
isolated waterspouts are possible in this activity. Showers and
isolated thunderstorms are likely early Friday morning ahead of the
approaching second area of low pressure.

LMZ261-362-364-366-563-565-567-868-031515-
Lake Michigan from Seul Choix Point to Rock Island Passage 5 NM
offshore to Mid Lake-
Lake Michigan South of a line from Seul Choix Point to the
Mackinac Bridge and north of a line from Charlevoix MI to South
Fox Island 5 NM offshore-
Lake Michigan from Charlevoix to Point Betsie MI 5 NM offshore to
Mid Lake-
Lake Michigan from Point Betsie to Manistee MI 5 NM offshore to
Mid Lake-
Lake Michigan from Rock Island Passage to Sturgeon Bay WI-
Lake Michigan from Sturgeon Bay to Two Rivers WI 5 NM offshore to
Mid Lake-
Lake Michigan from Two Rivers to Sheboygan WI 5 NM offshore to
Mid Lake-
Lake Michigan from Pentwater to Manistee MI 5 NM offshore to Mid
Lake-
253 AM CDT Wed Sep 3 2025

SHEBOYGAN WI TO PENTWATER MI NORTH...

.TODAY...Southwest winds to 30 kt veering to northwest 15 to
25 kt. Chance of waterspouts. Showers likely with a chance of
thunderstorms this morning, then chance of showers and
thunderstorms this afternoon. Waves 4 to 6 ft occasionally to
8 ft.
.TONIGHT...Northwest winds 15 to 25 kt diminishing to 10 to
20 kt. Slight chance of waterspouts. Slight chance of showers.
Waves 3 to 5 ft.
.THURSDAY...West winds 10 to 20 kt becoming southwest 15 to
25 kt. Waves 2 to 4 ft.
.THURSDAY NIGHT...Southwest winds 15 to 25 kt increasing to 30 kt
overnight. A few gale force gusts possible. Chance of showers in
the evening, then showers overnight. Waves 4 to 6 ft occasionally
to 8 ft building to 8 to 12 ft occasionally to 16 ft.
.FRIDAY...West winds to 30 kt diminishing to 25 kt. A few gale
force gusts possible in the morning. Showers in the morning.
Waves 8 to 12 ft occasionally to 16 ft subsiding to 7 to 10 ft
occasionally to 13 ft.
.FRIDAY NIGHT...West winds to 25 kt. Waves 4 to 7 ft occasionally
to 9 ft subsiding to 4 to 6 ft occasionally to 8 ft.
.SATURDAY...West winds 15 to 25 kt. Chance of showers. Waves 3 to
5 ft.
.SUNDAY...Northwest winds 10 to 20 kt. Waves 1 to 3 ft.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-031515-
Lake Michigan from Michigan City IN to St. Joseph MI 5 NM
offshore to Mid Lake-
Lake Michigan from Sheboygan to Port Washington WI 5 NM offshore
to Mid Lake-
Lake Michigan from Port Washington to North Point Light WI 5 NM
offshore to Mid Lake-
Lake Michigan from North Point Light to Wind Point WI 5 NM
offshore to Mid Lake-
Lake Michigan from Wind Point WI to Winthrop Harbor IL 5 NM
offshore to Mid Lake-
Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5 NM
offshore to Mid Lake-
Lake Michigan from Wilmette Harbor IL to Michigan City IN 5 NM
offshore to Mid Lake-
Lake Michigan from Whitehall to Pentwater MI 5 NM offshore to Mid
Lake-
Lake Michigan from Grand Haven to Whitehall MI 5 NM offshore to
Mid Lake-
Lake Michigan from Holland to Grand Haven MI 5 NM offshore to Mid
Lake-
Lake Michigan from South Haven to Holland MI 5 NM offshore to Mid
Lake-
Lake Michigan from St. Joseph to South Haven MI 5 NM offshore to
Mid Lake-
253 AM CDT Wed Sep 3 2025

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.TODAY...Southwest winds 15 to 25 kt becoming west 10 to 20 kt.
Chance of showers and slight chance of thunderstorms this
morning, then showers likely with a chance of thunderstorms this
afternoon. Waves 3 to 5 ft building to 4 to 6 ft occasionally to
8 ft.
.TONIGHT...Northwest winds 15 to 25 kt. Chance of showers and
slight chance of thunderstorms in the evening. Waves 4 to 7 ft
occasionally to 9 ft.
.THURSDAY...Northwest winds 10 to 20 kt becoming southwest. Waves
4 to 6 ft occasionally to 8 ft subsiding to 3 to 5 ft.
.THURSDAY NIGHT...Southwest winds 15 to 25 kt increasing to gales
to 35 kt overnight. Chance of showers. Waves 4 to 6 ft
occasionally to 8 ft building to 10 to 14 ft occasionally to
18 ft.
.FRIDAY...West gales to 40 kt diminishing to 30 kt in the
afternoon. Waves 10 to 14 ft occasionally to 18 ft.
.FRIDAY NIGHT...West winds 15 to 25 kt. Waves 5 to 8 ft
occasionally to 10 ft subsiding to 4 to 7 ft occasionally to
9 ft.
.SATURDAY...West winds 10 to 20 kt. Waves 4 to 6 ft occasionally
to 8 ft.
.SUNDAY...Northwest winds 10 to 20 kt. Waves 2 to 4 ft.

$$

LMZ761-031515-
MAFOR 0310/
MICHIGAN NORTH 11530 11546 11636 13730 12720. A chance of
waterspouts this morning. A chance of thunderstorms today. Waves
2 to 4 feet building to 3 to 6 feet today. Waves 3 to 5 feet
subsiding to 2 to 4 feet tonight.

MICHIGAN SOUTH 12530 11536 11626 11720 13730. A chance of
thunderstorms this afternoon. Waves 1 to 3 feet building to 3 to
5 feet today. Waves 3 to 6 feet tonight.

$$


Quigley

Experimental modernized open lake forecast is available online at
weather.gov/mkx/glftable

Graphical marine forecasts are available online at:
weather.gov/greatlakes