In July, Sarnia typically sees daytime highs of 27.1°C and overnight lows around 15.4°C. Compared to the annual average high of 13.3°C, July runs +13.7°C.
July in Sarnia averages a daytime high of 27.1°C and an overnight low of 15.4°C.
July runs +13.7°C compared to Sarnia's annual average high of 13.3°C, ranking #1 of 12 months by warmth.
Plan for daytime highs near 27.1°C and cooler evenings around 15.4°C.