428
FZUS63 KMKX 170740
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
240 AM CDT Thu Jul 17 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...

Stronger northerly with gusts of 30 knots will continue through the
morning as low pressure around 29.7 inches tracks across lake Huron.
Gusty winds will gradually weaken through the afternoon and evening
as high pressure around 30.2 inches moves across MN and over WI.
Lighter winds expected Thursday night into Friday as the high moves
over Lake Michigan before sliding east Friday afternoon. Then a warm
front will lift north-northeastward up across Lake Michigan later
Friday and stall across the mid-lake. Winds across the southern half
of the open waters will be southerly with more east-northeast winds
across northern portions of the lake north of the stalled front.
Another broad, weak low pressure around 29.8 inches looks to work
its way across the mid-lake later Saturday brining a period of
varying winds and thunderstorms. Then another high pressure around
30.1 inches sets up across the Upper Great Lakes for Sunday.

LMZ261-362-364-366-563-565-567-868-171515-
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-
240 AM CDT Thu Jul 17 2025

SHEBOYGAN WI TO PENTWATER MI NORTH...

.TODAY...North winds to 30 kt. Waves 5 to 8 ft occasionally to
10 ft subsiding to 4 to 7 ft occasionally to 9 ft.
.TONIGHT...North winds 15 to 25 kt becoming northeast 10 to 20 kt
late in the evening, then diminishing to 10 to 15 kt after
midnight becoming east late. Waves 4 to 6 ft occasionally to 8 ft
subsiding to 1 to 3 ft.
.FRIDAY...Southeast winds 5 to 10 kt becoming southwest 10 to
15 kt. Waves 1 to 2 ft.
.FRIDAY NIGHT...South winds 5 to 10 kt. Chance of showers. Waves
1 ft or less.
.SATURDAY...South winds 10 to 15 kt veering to northwest 10 to
20 kt. Chance of showers and thunderstorms in the morning, then
chance of showers in the afternoon. Waves 1 to 2 ft.
.SATURDAY NIGHT...North winds 10 to 15 kt. Waves 1 to 2 ft.
.SUNDAY...Northeast winds 10 to 15 kt becoming north. Waves 1 to
2 ft.
.MONDAY...Southeast winds 10 to 20 kt becoming east. Waves 1 to
3 ft.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-171515-
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-
240 AM CDT Thu Jul 17 2025

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.TODAY...North winds to 30 kt. Waves 5 to 8 ft occasionally to
10 ft.
.TONIGHT...North winds 15 to 25 kt diminishing to 10 to 20 kt
late in the evening, then becoming northeast after midnight
becoming east 10 to 15 kt late. Waves 4 to 7 ft occasionally to
9 ft subsiding to 3 to 5 ft.
.FRIDAY...East winds 10 to 15 kt diminishing to 5 to 10 kt. Waves
2 to 4 ft subsiding to 1 to 3 ft.
.FRIDAY NIGHT...East winds 5 to 10 kt becoming southeast. Chance
of showers overnight. Waves 1 to 2 ft.
.SATURDAY...South winds 10 to 15 kt becoming southwest. Chance of
showers in the morning, then chance of showers and thunderstorms
in the afternoon. Waves 1 to 2 ft.
.SATURDAY NIGHT...North winds 10 to 15 kt becoming northeast.
Waves 1 to 3 ft.
.SUNDAY...Northeast winds 10 to 15 kt. Waves 1 to 3 ft.
.MONDAY...Southeast winds 10 to 20 kt. Chance of showers. Waves
2 to 4 ft.

$$

LMZ761-171515-
MAFOR 1710/
MICHIGAN NORTH 14840 11830 11820 11110 11100. A chance of showers
early this morning. Waves 5 to 8 feet subsiding to 3 to 6 feet
today. Waves 3 to 5 feet subsiding to 1 to 3 feet tonight.

MICHIGAN SOUTH 11740 11830 12840 11830 11820 11120 11110. Waves 5
to 8 feet today. Waves 4 to 7 feet subsiding to 2 to 4 feet
tonight.

$$


Wagner

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

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