Lake Ontario Water Temperature

(Today) 2025

12.1°C / 53.7°F

The water will feel cool (fresh). Probably too cold for all but seasoned swimmers. We'd recommend a 4mm or 5mm wetsuit if you want to stay in the water.

*Live data from EAST Lake Ontario - 20NM North Northeast of Rochester, NY: 10.9°C / 51.6°F

Current weather

8°C / 47°F
(scattered clouds)
Partly cloudy
Wind
17 mph
Humidity
74%

The measurements for the water temperature in Lake Ontario, New York are provided by the daily satellite readings provided by the NOAA. The temperatures given are the sea surface temperature (SST) which is most relevant to recreational users.

*Live data may vary from satellite readings for a number of reasons. These include local factors, depth of smapling and time of day.

Water temp by month

Monthly average max / min water temperatures

The graph below shows the range of monthly Lake Ontario water temperature derived from many years of historical sea surface temperature data.

Lake Ontario average maximum / minimum water temperatures
Maximum and minimum monthly sea temperatures in Lake Ontario
  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Min °C 2.2 1.2 0.3 1 2.7 7.8 17.2 20.6 17.4 9.8 7.3 3.1
Max °C 4.7 4.4 4.2 6.1 8.3 22 25.6 24.8 23.2 18.6 11.1 7.7
Min °F 36.9 35.4 34.1 35.8 39.1 51.7 66.3 70.8 65.6 53.2 46.7 39.4
Max °F 39.4 38.6 38 40.9 44.7 65.9 74.7 75 71.4 62 50.5 44

The warmest water temperature is in August with an average around 72.9°F / 22.7°C. The coldest month is March with an average water temperature of 36°F / 2.2°C.

7 day tide forecast for Lake Ontario

MonTueWedThuFriSatSun
  • High 1:40am
    (1.58m)
  • Low 8:47am
    (0.05m)
  • High 2:07pm
    (1.67m)
  • Low 9:25pm
    (0.08m)
  • High 2:30am
    (1.58m)
  • Low 9:34am
    (0.02m)
  • High 2:50pm
    (1.75m)
  • Low 10:19pm
    (0.02m)
  • High 3:19am
    (1.58m)
  • Low 10:21am
    (0.01m)
  • High 3:32pm
    (1.8m)
  • Low 11:12pm
    (-0.01m)
  • High 4:08am
    (1.55m)
  • Low 11:08am
    (0.01m)
  • High 4:17pm
    (1.82m)
  • Low 12:05am
    (-0.02m)
  • High 5:00am
    (1.51m)
  • Low 11:57am
    (0.03m)
  • High 5:05pm
    (1.8m)
  • Low 12:58am
    (-0m)
  • High 5:57am
    (1.46m)
  • Low 12:48pm
    (0.05m)
  • High 6:01pm
    (1.74m)
  • Low 1:52am
    (0.02m)
  • High 6:58am
    (1.42m)
  • Low 1:41pm
    (0.09m)
  • High 7:05pm
    (1.67m)
7 day tide times for Lake Ontario

*These tide times are estimates based on the nearest accurate location (Troy, Hudson River, New York) and may differ by up to half an hour depending on distance. Please note, the tide times given are not suitable for navigational purposes.