In August, Sarnia typically sees daytime highs of 26.2°C and overnight lows around 14.9°C. Compared to the annual average high of 13.3°C, August runs +12.9°C.
August in Sarnia averages a daytime high of 26.2°C and an overnight low of 14.9°C.
August runs +12.9°C compared to Sarnia's annual average high of 13.3°C, ranking #2 of 12 months by warmth.
Plan for daytime highs near 26.2°C and cooler evenings around 14.9°C.