temperature in vallejo california
Vallejo, California Average Temperature. The average temperature for Vallejo is 57.45Â°F, 2.90Â°F higher than the nationwide average (54.55Â°F), and 4.20Â°F lower than the California average of 61.65Â°F. In the summer, temperatures rise to 65.1Â°F on average, 9.3% lower than average - one of the 20% lowest recorded averages. The winter average of 50.4Â°F is 23% higher than the U.S. average.