840
FZUS63 KMKX 050748
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
248 AM CDT Sat Jul 5 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...

Currently positioned over the northern Great Plains, 29.8 inch
low pressure will shift into the western Great Lakes today,
resulting in increasing southerly gusts across Lake Michigan. Said
low will progress across Michigan`s Upper Peninsula this evening,
dragging a cold front across the open waters in the process.
Areas of showers and thunderstorms are expected along and ahead of
the front. Widespread severe weather is not anticipated, though a
few strong storms with gusty winds are possible. The front will
linger near or just east of Lake Michigan during the day on
Sunday, with additional showers and scattered thunderstorms
possible through the afternoon hours. Precipitation will taper by
Sunday evening as the cold front moves into the Ohio River Valley.
North to northwest winds will become established across all of
the open waters behind the front by early Sunday evening.

30.0 inch high pressure will approach Lake Michigan during the
day on Monday, resulting in fair conditions and weakening
northerly winds. The high will cross the open waters Monday
evening and night, resulting in light and variable winds.
Generally light and variable winds will continue through mid-week
as a second area of 30.1 inch high pressure lingers across the
western Great Lakes. Periods of showers and embedded thunderstorms
return to the open waters Tuesday through late week as humidity
builds back into the Upper Midwest.

LMZ261-362-364-366-563-565-567-868-051515-
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-
248 AM CDT Sat Jul 5 2025

SHEBOYGAN WI TO PENTWATER MI NORTH...

.TODAY...Southwest winds 10 to 20 kt becoming south to 30 kt.
Slight chance of showers and thunderstorms this afternoon. Waves
3 to 5 ft.
.TONIGHT...Southwest winds to 30 kt diminishing to 15 to 25 kt
late in the evening, then diminishing to 10 to 20 kt after
midnight becoming west late. Showers likely with a chance of
thunderstorms in the evening, then chance of showers and
thunderstorms overnight. Waves 3 to 5 ft.
.SUNDAY...Northwest winds 10 to 20 kt becoming north 15 to 25 kt.
Waves 3 to 5 ft.
.SUNDAY NIGHT...North winds 15 to 25 kt diminishing to 10 to
20 kt. Waves 3 to 5 ft.
.MONDAY...North winds 10 to 15 kt increasing to 10 to 20 kt.
Waves 1 to 3 ft.
.MONDAY NIGHT...Northeast winds 10 to 15 kt veering to southeast
5 to 10 kt. Waves 1 to 2 ft.
.TUESDAY...South winds 5 to 10 kt becoming southwest 10 to 15 kt.
Waves 1 ft or less.
.WEDNESDAY...Northeast winds 5 to 10 kt becoming north 10 to
15 kt. Waves 1 ft or less.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-051515-
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-
248 AM CDT Sat Jul 5 2025

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.TODAY...Southwest winds 10 to 20 kt becoming south 15 to 25 kt.
Waves 3 to 5 ft.
.TONIGHT...South winds 15 to 25 kt becoming southwest 10 to
20 kt. Chance of showers and thunderstorms. Waves 3 to 5 ft.
.SUNDAY...Southwest winds 10 to 20 kt veering to north 15 to
25 kt. Chance of showers and thunderstorms. Waves 3 to 5 ft.
.SUNDAY NIGHT...North winds 15 to 25 kt diminishing to 10 to
20 kt. Waves 4 to 6 ft occasionally to 8 ft.
.MONDAY...North winds 10 to 15 kt increasing to 10 to 20 kt.
Waves 3 to 5 ft.
.MONDAY NIGHT...Northeast winds 10 to 15 kt diminishing to 5 to
10 kt. Waves 1 to 3 ft.
.TUESDAY...West winds 5 to 10 kt becoming south 10 to 15 kt.
Waves 1 to 2 ft.
.WEDNESDAY...Southeast winds 5 to 10 kt backing to northeast
10 to 15 kt. Waves 1 ft or less.

$$

LMZ761-051515-
MAFOR 0510/
MICHIGAN NORTH 11520 12430 12440 11536 12520. A chance of
thunderstorms tonight. Waves 1 to 3 feet building to 2 to 4 feet
today. Waves 3 to 5 feet subsiding to 2 to 4 feet tonight.

MICHIGAN SOUTH 11520 11420 13430 11530 12520. A chance of showers
and thunderstorms tonight. Waves 1 to 3 feet building to 2 to 4
feet today. Waves 2 to 4 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