In August, Sioux City typically sees daytime highs of 29.6°C and overnight lows around 16.1°C. Compared to the annual average high of 15.8°C, August runs +13.8°C.
August in Sioux City averages a daytime high of 29.6°C and an overnight low of 16.1°C.
August runs +13.8°C compared to Sioux City's annual average high of 15.8°C, ranking #2 of 12 months by warmth.
Plan for daytime highs near 29.6°C and cooler evenings around 16.1°C.