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Lake Ontario water temperature

Lake Ontario, Sodus Point, NY · Lake

The current water temperature at Lake Ontario is 19.6 °C (as of October 13, 2026, source: NOAA NDBC).

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

19.6 °C
Measured: October 13, 2026 · continuously updated
💧 Water 19.6° · ☀️ Air 18.9°
Temperature trend of recent weeks
Lake Ontario
Photo: DanielPenfield · CC BY-SA 4.0 · Wikimedia Commons

Measurement series & statistics

This measurement series includes 957 data points since August 17, 2026.

Lowest recorded value: 12.8 °C on September 22, 2026 · highest value: 23.7 °C on August 18, 2026.

In October, temperatures have ranged between 15.7 °C and 19.7 °C.

The current value is 3.1 °C above the October average of this series.

Nearby waters

More measuring points: Lake Ontario

Frequently asked questions

Can you swim at Lake Ontario right now?
The current water temperature is 19.6 °C. See live swimming conditions, weather and quality in the BrrChecker app.

How warm is the water at Lake Ontario?
Currently 19.6 °C (updated continuously).

How warm is at Lake Ontario in October?
In October, the water temperature recently averaged 16.5 °C.

When is the water warmest at Lake Ontario?
Across the measurement record, August is on average the warmest month (22.5 °C).

Open in the BrrChecker app

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