437
FZUS63 KMKX 210144
GLFLM
OPEN LAKE FORECAST FOR LAKE MICHIGAN
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
844 PM CDT MON APR 20 2026
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
HIGH PRESSURE AROUND 30.4 INCHES OVER LOWER MICHIGAN AND LOW
PRESSURE AROUND 29.7 INCHES DEVELOPING IN THE PLAINS WILL BRING
INCREASING SOUTHERLY WINDS TO LAKE MICHIGAN THROUGH TUESDAY
MORNING. A FEW GALES ARE POSSIBLE TONIGHT INTO EARLY TUESDAY
MORNING, ESPECIALLY OVER THE NORTHERN THIRD OF THE LAKE AS LOW
PRESSURE AROUND 29.5 INCHES ALSO PROGRESSES ACROSS THE HUDSON BAY.
THEN A COLD FRONT FROM THIS LOW WILL PROGRESS SOUTHWARD DOWN THE
LAKE TUESDAY AFTERNOON AND EVENING, WITH NORTHEASTERLY WINDS
BEHIND IT. HIGH PRESSURE AROUND 30.4 INCHES BUILDS INTO ONTARIO
ON WEDNESDAY, BRINGING LIGHT AND VARIABLE WINDS ACROSS THE LAKE.
WINDS WILL THEN BECOME SOUTHEAST AND INCREASE THURSDAY INTO
FRIDAY, AS STRONG LOW PRESSURE AROUND 29.2 INCHES DEVELOPS IN THE
NORTHERN PLAINS.
LMZ261-362-364-366-563-565-567-868-210915-
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-
844 PM CDT MON APR 20 2026
SHEBOYGAN WI TO PENTWATER MI NORTH...
REST OF TONIGHT
SOUTH WINDS TO 30 KT. WAVES 4 TO 7 FT
OCCASIONALLY TO 9 FT BUILDING TO 5 TO 8 FT OCCASIONALLY TO 10 FT.
TUESDAY
SOUTH WINDS 15 TO 25 KT BECOMING SOUTHWEST 10 TO
15 KT. WAVES 4 TO 7 FT OCCASIONALLY TO 9 FT SUBSIDING TO 4 TO
6 FT OCCASIONALLY TO 8 FT.
TUESDAY NIGHT
NORTH WINDS 5 TO 10 KT BECOMING NORTHEAST. WAVES
2 TO 4 FT SUBSIDING TO 1 TO 2 FT.
WEDNESDAY
NORTHEAST WINDS 5 TO 10 KT. WAVES 1 TO 2 FT.
WEDNESDAY NIGHT
EAST WINDS 5 TO 10 KT BECOMING SOUTHEAST
OVERNIGHT. WAVES 1 FT OR LESS BUILDING TO 1 TO 3 FT.
THURSDAY
SOUTH WINDS 10 TO 20 KT INCREASING TO 15 TO 25 KT.
WAVES 2 TO 4 FT BUILDING TO 4 TO 6 FT OCCASIONALLY TO 8 FT.
THURSDAY NIGHT
SOUTHEAST WINDS 15 TO 25 KT INCREASING TO
30 KT. CHANCE OF RAIN SHOWERS. WAVES 5 TO 8 FT OCCASIONALLY TO
10 FT.
FRIDAY
SOUTH WINDS 15 TO 25 KT DIMINISHING TO 10 TO 20 KT.
CHANCE OF RAIN SHOWERS. WAVES 5 TO 8 FT OCCASIONALLY TO 10 FT
SUBSIDING TO 4 TO 7 FT OCCASIONALLY TO 9 FT.
SATURDAY
NORTH WINDS 10 TO 20 KT. WAVES 3 TO 5 FT.
LMZ080-669-671-673-675-777-779-870-872-874-876-878-210915-
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-
844 PM CDT MON APR 20 2026
SHEBOYGAN WI TO PENTWATER MI SOUTH...
REST OF TONIGHT
SOUTHEAST WINDS 15 TO 25 KT BECOMING SOUTH.
WAVES 4 TO 6 FT OCCASIONALLY TO 8 FT.
TUESDAY
SOUTH WINDS TO 30 KT DIMINISHING TO 10 TO 20 KT.
CHANCE OF RAIN SHOWERS IN THE AFTERNOON. WAVES 4 TO 7 FT
OCCASIONALLY TO 9 FT SUBSIDING TO 3 TO 5 FT.
TUESDAY NIGHT
NORTH WINDS 10 TO 15 KT DIMINISHING TO 5 TO
10 KT. WAVES 2 TO 4 FT SUBSIDING TO 1 TO 2 FT.
WEDNESDAY
NORTHEAST WINDS 5 TO 10 KT BECOMING NORTH. WAVES
1 TO 2 FT.
WEDNESDAY NIGHT
EAST WINDS 5 TO 10 KT BECOMING SOUTH 10 TO
15 KT. WAVES 1 FT OR LESS BUILDING TO 1 TO 3 FT.
THURSDAY
SOUTH WINDS 10 TO 20 KT INCREASING TO 15 TO 25 KT.
WAVES 2 TO 4 FT BUILDING TO 4 TO 6 FT OCCASIONALLY TO 8 FT.
THURSDAY NIGHT
SOUTH WINDS 15 TO 25 KT. CHANCE OF SHOWERS.
WAVES 5 TO 8 FT OCCASIONALLY TO 10 FT.
FRIDAY
SOUTH WINDS 15 TO 25 KT DIMINISHING TO 10 TO 20 KT.
SHOWERS LIKELY. WAVES 5 TO 8 FT OCCASIONALLY TO 10 FT SUBSIDING
TO 4 TO 7 FT OCCASIONALLY TO 9 FT.
SATURDAY
NORTH WINDS 10 TO 20 KT. WAVES 4 TO 6 FT OCCASIONALLY
TO 8 FT.
LMZ761-210915-
MAFOR 2104/
MICHIGAN NORTH 13440 11520 12510 11800 11110. WAVES 4 TO 7 FEET
OVERNIGHT. WAVES 3 TO 6 FEET SUBSIDING TO 2 TO 4 FEET TUESDAY.
WAVES 1 TO 3 FEET TUESDAY EVENING.
MICHIGAN SOUTH 14430 11430 11420 11410 11810. A CHANCE OF RAIN
SHOWERS TUESDAY AFTERNOON. A CHANCE OF SHOWERS TUESDAY EVENING.
WAVES 3 TO 6 FEET OVERNIGHT. WAVES 3 TO 6 FEET SUBSIDING TO 2 TO
4 FEET TUESDAY. WAVES 1 TO 3 FEET TUESDAY EVENING.
WAGNER
EXPERIMENTAL MODERNIZED OPEN LAKE FORECAST IS AVAILABLE ONLINE AT
WEATHER.GOV/MKX/GLFTABLE
GRAPHICAL MARINE FORECASTS ARE AVAILABLE ONLINE AT:
WEATHER.GOV/GREATLAKES
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