August weather in Foster City, CA
The average temperature in Foster City in August is 68.7°F (56.5°F–80.8°F). Average precipitation: 0.04 inches.
August is a summer month in Foster City, and is warmer than the annual average of 59.4°F. Daily temperatures swing about 24.3°F between overnight low and afternoon high. Expect about 0 days with precipitation. Daylight averages about 13h 27m. For travel, August is a comfortable month to visit.
Avg High
80.8°F
Avg Low
56.5°F
Precipitation
0.04 in
Daylight
13h 27m
August records in Foster City
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 104.0°F (1993) | 46.0°F (1937) | 0.00 in (1913) |
| August 2 | 102.9°F (1946) | 48.0°F (1956) | 0.00 in (1913) |
| August 3 | 104.0°F (1998) | 46.0°F (1956) | 0.00 in (1913) |
| August 4 | 99.0°F (1947) | 44.1°F (1934) | 0.00 in (1913) |
| August 5 | 98.1°F (1964) | 44.1°F (1954) | 0.00 in (1913) |
| August 6 | 102.9°F (1983) | 43.0°F (1979) | 0.00 in (1913) |
| August 7 | 105.1°F (1983) | 45.0°F (1975) | 0.00 in (1913) |
| August 8 | 98.1°F (1984) | 45.0°F (1934) | 0.00 in (1913) |
| August 9 | 100.0°F (1970) | 46.0°F (1934) | 0.03 in (1999) |
| August 10 | 99.0°F (1970) | 46.0°F (1931) | 0.00 in (1913) |
| August 11 | 102.0°F (1937) | 46.9°F (1932) | 0.07 in (1965) |
| August 12 | 100.0°F (1959) | 48.0°F (1932) | 0.00 in (1913) |
| August 13 | 95.0°F (1935) | 48.0°F (1946) | 0.15 in (1991) |
| August 14 | 102.9°F (2020) | 48.0°F (1934) | 0.10 in (1916) |
| August 15 | 100.0°F (2019) | 48.0°F (1946) | 0.27 in (1976) |
| August 16 | 100.9°F (2015) | 45.0°F (1932) | 0.00 in (1913) |
| August 17 | 102.0°F (1939) | 43.0°F (1932) | 0.01 in (1976) |
| August 18 | 99.0°F (1934) | 44.1°F (1931) | 0.46 in (1975) |
| August 19 | 97.0°F (1950) | 45.0°F (1931) | 0.22 in (1976) |
| August 20 | 97.0°F (1964) | 46.0°F (1932) | 0.81 in (1997) |
| August 21 | 97.0°F (2025) | 46.9°F (1931) | 0.01 in (1968) |
| August 22 | 96.1°F (1974) | 44.1°F (1973) | 0.02 in (1976) |
| August 23 | 96.1°F (1931) | 48.0°F (1932) | 0.00 in (1913) |
| August 24 | 104.0°F (2010) | 46.0°F (1955) | 0.02 in (1959) |
| August 25 | 102.0°F (1988) | 45.0°F (1955) | 0.35 in (1971) |
| August 26 | 100.9°F (1944) | 46.0°F (1952) | 0.31 in (1935) |
| August 27 | 102.0°F (1981) | 46.0°F (1931) | 0.19 in (1949) |
| August 28 | 100.9°F (2009) | 45.0°F (1933) | 0.02 in (1949) |
| August 29 | 102.0°F (1968) | 45.0°F (1932) | 0.05 in (1992) |
| August 30 | 100.9°F (1968) | 42.1°F (1939) | 0.20 in (1984) |
| August 31 | 96.1°F (2025) | 46.0°F (1955) | 0.08 in (1964) |