In August, San Juan typically sees daytime highs of 18.9°C and overnight lows around 2.2°C. Compared to the annual average high of 24.0°C, August runs -5.1°C.
August in San Juan averages a daytime high of 18.9°C and an overnight low of 2.2°C.
August runs -5.1°C compared to San Juan's annual average high of 24.0°C, ranking #10 of 12 months by warmth.
Plan for daytime highs near 18.9°C and cooler evenings around 2.2°C.