737
FZUS63 KMKX 181947
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
247 PM CDT Sat Oct 18 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...

Modest southerly winds continue through the early evening hours.
Low pressure is expected to move in from the Great Plains across
IL and northern IN tonight, and rapidly deepen to around 29.2
inches as it lifts into the Lower Michigan Sunday morning,
reaching Lake Huron by mid day Sunday. This will drag a strong
cold front across the lake, resulting in northwest gales early
Sunday morning through Sunday evening.

Winds briefly weaken late Sunday night into early Monday, then
turn south and accelerate to roughly 30 knots mid day Monday as
29.5 inch low pressure tracks east across northern Minnesota. This
low will then drag another cold front across the lake Monday
night, with west gales looking likely behind the front late Monday
night through Tuesday night, possibly into Wednesday as the
aforementioned low pressure lingers over southern Canada.

LMZ261-362-364-366-563-565-567-868-190330-
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-
247 PM CDT Sat Oct 18 2025

SHEBOYGAN WI TO PENTWATER MI NORTH...

...GALE WARNING IN EFFECT FROM SUNDAY MORNING THROUGH SUNDAY
EVENING...

.TONIGHT...South winds 10 to 15 kt diminishing to 5 to 10 kt late
this evening, then veering to north 10 to 20 kt after midnight
increasing to 30 kt late. Showers and slight chance of
thunderstorms overnight. Waves 2 to 4 ft building to 3 to 5 ft.
.SUNDAY...North gales to 35 kt becoming northwest gales to 40 kt.
Showers in the morning, then chance of showers in the afternoon.
Waves 6 to 9 ft occasionally to 12 ft building to 10 to 14 ft
occasionally to 18 ft.
.SUNDAY NIGHT...Northwest gales to 40 kt diminishing to 15 to
25 kt. Waves 8 to 11 ft occasionally to 14 ft subsiding to 4 to
6 ft occasionally to 8 ft.
.MONDAY...West winds 10 to 20 kt becoming south to 30 kt in the
afternoon. Waves 2 to 4 ft building to 8 to 11 ft occasionally to
14 ft.
.MONDAY NIGHT...South gales to 35 kt. Chance of showers in the
evening, then showers overnight. Waves 8 to 12 ft occasionally to
16 ft.
.TUESDAY...West gales to 40 kt increasing to gales to 45 kt.
Showers. Waves 8 to 11 ft occasionally to 14 ft building to 10 to
14 ft occasionally to 18 ft.
.TUESDAY NIGHT...West gales to 45 kt becoming northwest gales to
40 kt. Rain showers. Waves 10 to 14 ft occasionally to 18 ft.
.WEDNESDAY...Northwest gales to 35 kt. Rain showers likely. Waves
7 to 10 ft occasionally to 13 ft subsiding to 4 to 7 ft
occasionally to 9 ft.
.THURSDAY...Northwest winds to 30 kt diminishing to 15 to 25 kt.
Chance of rain showers. Waves 2 to 4 ft.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-190330-
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-
247 PM CDT Sat Oct 18 2025

SHEBOYGAN WI TO PENTWATER MI SOUTH...

...GALE WARNING IN EFFECT FROM SUNDAY MORNING THROUGH SUNDAY
EVENING...

.TONIGHT...South winds 5 to 10 kt increasing to 10 to 15 kt late
this evening, then veering to west 10 to 20 kt after midnight
becoming northwest to 30 kt late. Chance of showers and
thunderstorms this evening, then showers and slight chance of
thunderstorms overnight. Waves 2 to 4 ft building to 3 to 5 ft.
.SUNDAY...Northwest gales to 35 kt increasing to gales to 40 kt.
Showers in the morning, then chance of showers in the afternoon.
Waves 8 to 11 ft occasionally to 14 ft building to 14 to 18 ft
occasionally to 23 ft.
.SUNDAY NIGHT...Northwest gales to 40 kt diminishing to 15 to
25 kt. Waves 14 to 18 ft occasionally to 23 ft subsiding to 6 to
9 ft occasionally to 12 ft.
.MONDAY...West winds 10 to 20 kt becoming south to 30 kt in the
afternoon. Waves 4 to 7 ft occasionally to 9 ft building to 8 to
11 ft occasionally to 14 ft.
.MONDAY NIGHT...South gales to 35 kt becoming southwest. Showers
likely. Waves 8 to 12 ft occasionally to 16 ft.
.TUESDAY...West gales to 40 kt increasing to gales to 45 kt.
Chance of showers in the morning, then showers likely in the
afternoon. Waves 12 to 16 ft occasionally to 21 ft.
.TUESDAY NIGHT...West gales to 45 kt becoming northwest. Chance
of showers. Waves 14 to 18 ft occasionally to 23 ft.
.WEDNESDAY...Northwest gales to 40 kt. Chance of rain showers.
Waves 10 to 14 ft occasionally to 18 ft subsiding to 7 to 10 ft
occasionally to 13 ft.
.THURSDAY...Northwest winds to 30 kt diminishing to 10 to 20 kt.
Waves 4 to 6 ft occasionally to 8 ft.

$$

LMZ761-190330-
MAFOR 1822/
MICHIGAN NORTH...GALE WARNING IN EFFECT...11410 11400 11620 11836
12856 12750. Waves 1 to 3 feet building to 2 to 4 feet tonight.
Waves 5 to 8 feet building to 8 to 12 feet Sunday.

MICHIGAN SOUTH...GALE WARNING IN EFFECT...11410 11416 11516 11736
12756 12750. A chance of thunderstorms this evening. Waves 2 to 4
feet subsiding to 1 to 3 feet, then building to 2 to 4 feet
tonight. Waves 7 to 10 feet building to 14 to 18 feet Sunday.

$$


Sheppard

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

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