Lake Ontario water temperature

Lake Ontario, Niagara-on-the-Lake (ECCC) · Lake

The current water temperature at Lake Ontario is 22.6 °C (as of September 5, 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.

22.6 °C

Measured: September 5, 2026 · continuously updated

💧 Water 22.6° · ☀️ Air 18.4° · high today 23.2°

Nearby waters

Eighteenmile Creek at Burt, New York · 28.7 km away21.8 °C Erie (Barge) C above Halls Waste Weir at Lockport, New York · 31.4 km away21.5 °C Lake Erie, Fort Erie (ECCC) · 37.9 km away23.1 °C Lake Ontario, Grimsby · 41.0 km away19.2 °C Atlantic, Emerald Beach · 43.4 km away22.9 °C

More measuring points: Lake Ontario

Sodus Point Nearshore Monitoring23.0 °C Oswego, NY (274)22.4 °C Oswego22.3 °C Sodus Point, NY22.2 °C Wolfe Island (ECCC)22.2 °C Oak Orchard, NY21.9 °C

Frequently asked questions

Can you swim at Lake Ontario right now?
The current water temperature is 22.6 °C. See live swimming conditions, weather and quality in the BrrChecker app.

How warm is the water at Lake Ontario?
Currently 22.6 °C (updated continuously).

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