In December, San Diego typically sees daytime highs of 19.3°C and overnight lows around 8.1°C. Compared to the annual average high of 22.1°C, December runs -2.8°C.
December in San Diego averages a daytime high of 19.3°C and an overnight low of 8.1°C.
December runs -2.8°C compared to San Diego's annual average high of 22.1°C, ranking #9 of 12 months by warmth.
Plan for daytime highs near 19.3°C and cooler evenings around 8.1°C.