In December, Mission Viejo typically sees daytime highs of 19.5°C and overnight lows around 6.2°C. Compared to the annual average high of 23.2°C, December runs -3.7°C.
December in Mission Viejo averages a daytime high of 19.5°C and an overnight low of 6.2°C.
December runs -3.7°C compared to Mission Viejo's annual average high of 23.2°C, ranking #10 of 12 months by warmth.
Plan for daytime highs near 19.5°C and cooler evenings around 6.2°C.