Marine Forecast
Illustrated map of Lake Michigan at Chicago

Marine forecast

Calumet Harbor IL to Gary

current wind
8 kt WSW
Gusts
13 kt
Seas
0.7 ft
Air
78°F
72-hr peak
24 kt

Observed Tue 1:54 PM | LMZ743

Gusts now
13 kt
Seas now
0.7 ft
Air
78°F
72-hr peak
24 kt
Peak seas
6 ft

In brief

At 1:54 pm CDT on Oct 13, 2026, NDBC station CMTI2 (Calumet Harbor, IL, 6 miles away) measured wind from the WSW at 8 kt, gusting to 13 kt; buoy 45198 measured seas of 0.7 ft. The NWS forecast for Calumet Harbor IL to Gary issued at 9:41 am CDT on Oct 13, 2026 reads, for rest of today: “West winds 10 to 20 kt becoming north and diminishing to around 10 kt in the afternoon. Partly cloudy.”

Source: National Weather Service Chicago/Romeoville IL forecast; NDBC observations

Wind forecast · ktPeak 24 kt

05101520253035Wed 14Thu 15Fri 1605101520253035Wed 14Thu 15Fri 16
Sustained GustOct 13-16 | CDT

Seas forecast · ftPeak 6 ft

0123456Wed 14Thu 15Fri 160123456Wed 14Thu 15Fri 16
Oct 13-16 | CDT

NWS marine forecast

PeriodForecast
Rest Of TodayWest winds 10 to 20 kt becoming north and diminishing to around 10 kt in the afternoon. Partly cloudy. Waves 1 to 3 ft.
TonightNortheast winds around 5 kt. Showers and thunderstorms likely. Waves 1 to 2 ft.
WednesdayNortheast winds 10 to 20 kt becoming north and increasing to. Chance of showers in the morning. Waves 1 to 2 ft building to 3 to 5 ft.
Wednesday NightNortheast winds 10 to 20 kt becoming east 10 to 15 kt overnight. Slight chance of rain overnight. Waves 4 to 6 ft occasionally to 8 ft. A small craft advisory will likely be needed.

Issued Tue 9:41 AM by Chicago/Romeoville IL (product NSHLOT).

TimeWindGustSeasWater
Tue 1:54 PM 8 kt WSW 13 kt — —
Tue 12:54 PM 8 kt SW 13 kt — —
Tue 11:54 AM 5 kt SW 8 kt — —
Tue 10:54 AM 5 kt SW 12 kt — —
Tue 9:54 AM 7 kt WSW 13 kt — —
Tue 8:54 AM 6 kt WSW 14 kt — —
Tue 7:54 AM 6 kt SW 10 kt — —
Tue 6:54 AM 4 kt SW 6 kt — —
Tue 5:54 AM 6 kt SSW 8 kt — —
Tue 4:54 AM 7 kt SSW 10 kt — —
Tue 3:54 AM 7 kt SSW 10 kt — —
Tue 2:54 AM 8 kt SSW 14 kt — —

Observed Tue 1:54 PM at NDBC buoy CMTI2 (Calumet Harbor, IL), 5.6 miles away. Seas from buoy 45198 (Chicago Buoy), 15.5 miles away, at Tue 2:10 PM.

What is the marine forecast for Calumet Harbor IL to Gary today?

Rest Of Today: West winds 10 to 20 kt becoming north and diminishing to around 10 kt in the afternoon. Partly cloudy. Waves 1 to 3 ft.

Is there a small craft advisory for Calumet Harbor IL to Gary?

No advisories, warnings or watches are in effect for NWS zone LMZ743 as of the last update on this page. Advisories can be issued at any time; check the current bulletin before leaving the dock.

How high are the waves at Calumet Harbor IL to Gary right now?

Seas are running 0.7 ft, measured at NDBC buoy CMTI2 Tue 1:54 PM, 5.6 miles from this zone. The forecast peaks at 6.0 ft Fri 2 PM.

What do the wind speeds in knots mean?

One knot is 1.15 mph. The National Weather Service issues a small craft advisory for sustained winds of roughly 22–33 knots or hazardous seas, a gale warning at 34–47 knots, and a storm warning at 48 knots and above. Exact advisory thresholds vary by forecast office and by water body — a bay reaches dangerous chop at a lower wind speed than open ocean.

Where does this forecast come from?

The forecast text is the National Weather Service's own marine bulletin for zone LMZ743, issued by Chicago/Romeoville IL, reproduced in full. The wind and seas charts are drawn from the NWS gridded forecast for a point inside the zone. Observations come from the nearest reporting NDBC buoy. We are not affiliated with NOAA or the National Weather Service.

Forecast: NOAA/NWS product NSHLOT, issued Tue 9:41 AM. Observations: NOAA National Data Buoy Center station CMTI2, read Tue 1:54 PM. Retrieved Oct 13, 2:42 PM. Conditions offshore change faster than any page can be rebuilt, so check the current NWS bulletin and your own instruments before going out.