423
FZUS63 KMKX 161723
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
1223 PM CDT Wed Jul 16 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...

Southerly winds will increase this morning ahead of an
approaching low pressure around 29.7 inches and accompanying
front. Expect the low pressure over northern IA to move across
southern WI this afternoon and cross the middle portion of Lake
Michigan through the evening. Accompanying this system will be
increased thunderstorm chances which may produce strong, gusty
winds across Lake Michigan through the late afternoon and evening.
Will first see northerly winds gradually build down across the
northern half of the lake through the afternoon as the front
shifts southeast ahead the low pressure, which will move across
the Lake later this evening/tonight. Expect breezy northerly winds
to migrate into the southern half of the lake overnight and
persist into Thursday as high pressure around 30.2 inches builds
into the Upper Midwest. Lighter, shifting winds are expected for
Friday as the high pressure moves over the Upper Great Lakes.
Increasing southerly flow then returns for the start of the
weekend.

LMZ261-362-364-366-563-565-567-868-170300-
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-
1223 PM CDT Wed Jul 16 2025

SHEBOYGAN WI TO PENTWATER MI NORTH...

.TONIGHT...North winds 15 to 25 kt. Showers likely with a chance
of thunderstorms. Waves 3 to 5 ft building to 4 to 7 ft
occasionally to 9 ft.
.THURSDAY...North winds 15 to 25 kt increasing to 30 kt. Waves
4 to 7 ft occasionally to 9 ft.
.THURSDAY NIGHT...North winds 15 to 25 kt becoming northeast
10 to 15 kt overnight. Waves 4 to 6 ft occasionally to 8 ft
subsiding to 2 to 4 ft.
.FRIDAY...Southeast winds 5 to 10 kt veering to southwest 10 to
15 kt. Waves 1 to 2 ft.
.FRIDAY NIGHT...South winds 5 to 10 kt. Waves 1 ft or less.
.SATURDAY...South winds 10 to 15 kt. Chance of showers. Waves
1 ft or less.
.SUNDAY...North winds 10 to 15 kt increasing to 10 to 20 kt.
Waves 1 to 2 ft.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-170300-
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-
1223 PM CDT Wed Jul 16 2025

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.TONIGHT...South winds 15 to 25 kt veering to northwest. Showers
likely with a chance of thunderstorms in the evening, then chance
of showers and thunderstorms overnight. Waves 2 to 4 ft building
to 4 to 7 ft occasionally to 9 ft.
.THURSDAY...Northwest winds 15 to 25 kt becoming north to 30 kt.
Waves 6 to 9 ft occasionally to 12 ft.
.THURSDAY NIGHT...North winds 15 to 25 kt becoming northeast
10 to 20 kt. Waves 5 to 8 ft occasionally to 10 ft subsiding to
4 to 6 ft occasionally to 8 ft.
.FRIDAY...East winds 10 to 15 kt becoming northeast 5 to 10 kt.
Waves 2 to 4 ft subsiding to 1 to 3 ft.
.FRIDAY NIGHT...Northeast winds 5 to 10 kt veering to southeast.
Waves 1 to 2 ft.
.SATURDAY...South winds 10 to 15 kt. Chance of showers. Waves
1 to 2 ft.
.SUNDAY...North winds 10 to 15 kt increasing to 10 to 20 kt.
Waves 1 to 3 ft.

$$
LMZ761-170300-
MAFOR 1622 AMD/
MICHIGAN NORTH 11840 13846 11840 11830 12840. A chance of
thunderstorms tonight. Waves 2 to 4 feet building to 4 to 7 feet
tonight. Waves 4 to 7 feet subsiding to 3 to 6 feet Thursday.

MICHIGAN SOUTH 11436 11636 13730 11830 12840. A chance of
thunderstorms tonight. Waves 2 feet or less building to 4 to 7
feet tonight. Waves 4 to 7 feet Thursday.

$$


WFO MKX

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

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