789
FZUS53 KLOT 200720
NSHLOT

Nearshore Marine Forecast
National Weather Service Chicago/Romeoville IL
220 AM CDT Mon Jul 20 2026

For waters within 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 waves, along with the
average height of the highest 10 percent of the waves which will
occasionally be encountered.

LMZ740>742-202130-
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
220 AM CDT Mon Jul 20 2026

.EARLY THIS MORNING...Nearly calm winds. Patchy smoke. Waves
around 1 ft.
.TODAY...South winds around 10 kt increasing to 15 to 25 kt.
Smoke in the morning. Waves 1 to 2 ft building to 2 to 4 ft.
.TONIGHT...Southwest winds 15 to 25 kt becoming west. Scattered
showers and thunderstorms. Waves 2 to 4 ft subsiding to 1 to 3 ft.
.TUESDAY...West winds 15 to 25 kt becoming northwest to 30 kt in
the evening. Isolated showers in the afternoon. Waves 1 to 3 ft
building to 2 to 4 ft.
.TUESDAY NIGHT...North winds to 30 kt diminishing to 15 to 25 kt.
Isolated showers in the evening. Waves 5 to 8 ft occasionally to
10 ft building to 7 to 10 ft occasionally to 13 ft. A small craft
advisory will likely be needed.

$$

LMZ743>745-202130-
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
220 AM CDT Mon Jul 20 2026

.EARLY THIS MORNING...Nearly calm winds. Patchy Smoke. Waves
around 1 ft.
.TODAY...South winds 10 to 20 kt. Smoke in the morning. Waves
1 to 2 ft.
.TONIGHT...Southwest winds 15 to 25 kt. Scattered showers and
thunderstorms after midnight. Waves 1 to 2 ft building to 2 to 4
ft.
.TUESDAY...West winds 15 to 25 kt becoming northwest in the
afternoon. Isolated showers in the afternoon. Waves 2 to 4 ft.
.TUESDAY NIGHT...North winds to 30 kt. Isolated showers in the
evening. Waves 6 to 9 ft occasionally to 12 ft building to 8 to
11 ft occasionally to 14 ft. A small craft advisory will likely
be needed.

$$

Borchardt