In August, Ontario typically sees daytime highs of 31.4°C and overnight lows around 15.5°C. Compared to the annual average high of 23.1°C, August runs +8.3°C.
August in Ontario averages a daytime high of 31.4°C and an overnight low of 15.5°C.
August runs +8.3°C compared to Ontario's annual average high of 23.1°C, ranking #2 of 12 months by warmth.
Plan for daytime highs near 31.4°C and cooler evenings around 15.5°C.