Lake Ontario, Oswego · Lake
The current water temperature at Lake Ontario is 24.2 °C (as of August 7, 2026, source: GLOS).
Can you swim at Lake Ontario right now?
The current water temperature is 24.2 °C. See live swimming conditions, weather and quality in the BrrChecker app.
How warm is the water at Lake Ontario?
Currently 24.2 °C (updated continuously).
How warm is at Lake Ontario in August?
In August, the water temperature recently averaged 23.0 °C.