In August, Washington typically sees daytime highs of 18.0°C and overnight lows around 10.5°C. Compared to the annual average high of 11.4°C, August runs +6.6°C.
August in Washington averages a daytime high of 18.0°C and an overnight low of 10.5°C.
August runs +6.6°C compared to Washington's annual average high of 11.4°C, ranking #2 of 12 months by warmth.
Plan for daytime highs near 18.0°C and cooler evenings around 10.5°C.