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Lake Ontario water temperature

Lake Ontario, West Lake Ontario (OMECP) · Lake

The current water temperature at Lake Ontario is 18.6 °C (as of September 6, 2026, source: GLOS).

Lakes stratify in summer: bathing-warm on top, markedly colder a few metres down. Measurements are taken at the surface — right where you swim.

18.6 °C
Measured: September 6, 2026 · continuously updated
💧 Water 18.6° · ☀️ Air 17.7° · high today 22.0°
Temperature trend of recent weeks

Nearby waters

Lake Ontario, Marie Curtis Park East Beach · 2.8 km away15.0 °CLake Ontario, Sunnyside Beach · 8.7 km away15.0 °CLake Ontario, Hanlan's Point Beach · 10.7 km away20.0 °CLake Ontario, Gibraltar Point Beach · 11.3 km away20.0 °CLake Ontario, Centre Island Beach · 12.1 km away20.0 °C

More measuring points: Lake Ontario

Sodus Point Nearshore Monitoring23.0 °CNiagara-on-the-Lake (ECCC)22.6 °COswego, NY (274)22.4 °COswego22.3 °CSodus Point, NY22.2 °CWolfe Island (ECCC)22.2 °C

Frequently asked questions

Can you swim at Lake Ontario right now?
The current water temperature is 18.6 °C. See live swimming conditions, weather and quality in the BrrChecker app.

How warm is the water at Lake Ontario?
Currently 18.6 °C (updated continuously).

Open in the BrrChecker app

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