December weather in Foster City, CA

The average temperature in Foster City in December is 49.4°F (40.2°F–58.6°F). Average precipitation: 3.92 inches.

December is a winter month in Foster City, and is cooler than the annual average of 59.4°F. Daily temperatures swing about 18.4°F between overnight low and afternoon high. Expect about 9 days with precipitation. Daylight averages about 9h 25m. For travel, December is a comfortable month to visit.

Avg High
58.6°F
Avg Low
40.2°F
Precipitation
3.92 in
Daylight
9h 25m

December records in Foster City

Date Record High Record Low Record Precip
December 1 73.0°F (1943) 30.0°F (1931) 2.49 in (1952)
December 2 75.0°F (1941) 30.0°F (1936) 1.97 in (2014)
December 3 73.0°F (1959) 28.0°F (1936) 2.15 in (1950)
December 4 73.9°F (1958) 28.0°F (1936) 2.19 in (1915)
December 5 73.0°F (1976) 27.0°F (2013) 1.95 in (1909)
December 6 75.0°F (2024) 28.0°F (1931) 1.17 in (1992)
December 7 75.0°F (1934) 21.9°F (1998) 2.76 in (1952)
December 8 75.0°F (2024) 25.0°F (1978) 1.50 in (1909)
December 9 73.9°F (1934) 21.9°F (1972) 1.15 in (1908)
December 10 71.1°F (1934) 25.0°F (1972) 2.00 in (1937)
December 11 72.0°F (1958) 23.0°F (1932) 4.19 in (2014)
December 12 75.9°F (1958) 18.0°F (1932) 2.43 in (1995)
December 13 70.0°F (1953) 19.0°F (1932) 2.09 in (2021)
December 14 71.1°F (1958) 21.9°F (1932) 2.67 in (1915)
December 15 72.0°F (1980) 19.9°F (1932) 1.86 in (1957)
December 16 73.9°F (1998) 26.1°F (1932) 2.15 in (2002)
December 17 73.0°F (1958) 27.0°F (1965) 1.40 in (1977)
December 18 70.0°F (1998) 27.0°F (1965) 1.06 in (1970)
December 19 70.0°F (1999) 28.9°F (1935) 3.04 in (1955)
December 20 71.1°F (1944) 28.0°F (1965) 1.58 in (1981)
December 21 70.0°F (1999) 24.1°F (1968) 1.94 in (1982)
December 22 68.0°F (1999) 19.0°F (1990) 2.56 in (1982)
December 23 69.1°F (2014) 21.0°F (1990) 4.00 in (1955)
December 24 72.0°F (2013) 21.9°F (1990) 1.32 in (1931)
December 25 75.0°F (1967) 25.0°F (1998) 1.93 in (2008)
December 26 73.9°F (1967) 25.0°F (1998) 1.82 in (1948)
December 27 75.0°F (1967) 28.0°F (1990) 2.83 in (1931)
December 28 73.9°F (1967) 26.1°F (1930) 1.41 in (1951)
December 29 72.0°F (2025) 21.9°F (1930) 2.46 in (1981)
December 30 69.1°F (1958) 24.1°F (1930) 1.06 in (1907)
December 31 70.0°F (1958) 28.0°F (1990) 4.47 in (2022)

Other months in Foster City