August weather in Herndon, VA
The average temperature in Herndon in August is 75.7°F (65.2°F–86.3°F). Average precipitation: 3.53 inches.
August is a summer month in Herndon, and is warmer than the annual average of 55.7°F. Daily temperatures swing about 21.1°F between overnight low and afternoon high. Expect about 9 days with precipitation. Daylight averages about 13h 32m. For travel, August is a comfortable month to visit.
Avg High
86.3°F
Avg Low
65.2°F
Precipitation
3.53 in
Daylight
13h 32m
August records in Herndon
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 100.0°F (1980) | 54.0°F (1997) | 1.09 in (2018) |
| August 2 | 100.9°F (2024) | 52.0°F (1998) | 1.37 in (2004) |
| August 3 | 99.0°F (1991) | 50.0°F (1976) | 1.03 in (1970) |
| August 4 | 99.0°F (2002) | 51.1°F (1976) | 1.87 in (2020) |
| August 5 | 99.0°F (1995) | 54.0°F (1985) | 1.78 in (1990) |
| August 6 | 96.1°F (1977) | 50.0°F (1966) | 2.49 in (1986) |
| August 7 | 97.0°F (2007) | 48.9°F (1994) | 2.33 in (2000) |
| August 8 | 100.9°F (2007) | 48.9°F (1989) | 1.39 in (2024) |
| August 9 | 97.0°F (1980) | 46.9°F (1989) | 2.28 in (1969) |
| August 10 | 97.0°F (2009) | 51.1°F (1999) | 2.38 in (1984) |
| August 11 | 99.0°F (2021) | 46.9°F (1972) | 4.68 in (1984) |
| August 12 | 100.0°F (2021) | 51.1°F (1962) | 2.07 in (1996) |
| August 13 | 99.0°F (2016) | 50.0°F (1964) | 1.48 in (2003) |
| August 14 | 100.0°F (1985) | 48.9°F (1983) | 1.12 in (2008) |
| August 15 | 102.0°F (1988) | 45.0°F (1964) | 2.18 in (2019) |
| August 16 | 100.0°F (1997) | 46.0°F (1979) | 1.45 in (2003) |
| August 17 | 100.9°F (1988) | 44.1°F (1979) | 3.32 in (1997) |
| August 18 | 98.1°F (2009) | 45.0°F (1981) | 1.39 in (2010) |
| August 19 | 95.0°F (2002) | 51.1°F (1998) | 1.54 in (1967) |
| August 20 | 104.0°F (1983) | 46.9°F (1964) | 2.17 in (1963) |
| August 21 | 96.1°F (1962) | 46.9°F (1976) | 2.72 in (2018) |
| August 22 | 100.9°F (1983) | 48.9°F (2024) | 0.94 in (2009) |
| August 23 | 96.1°F (1998) | 46.9°F (1981) | 1.60 in (2001) |
| August 24 | 97.0°F (1998) | 46.0°F (1971) | 3.88 in (1967) |
| August 25 | 97.0°F (1998) | 46.9°F (1971) | 3.03 in (1999) |
| August 26 | 95.0°F (1975) | 48.0°F (1977) | 1.48 in (1965) |
| August 27 | 100.0°F (1987) | 46.0°F (1969) | 1.98 in (1971) |
| August 28 | 99.0°F (2024) | 44.1°F (1986) | 1.73 in (2002) |
| August 29 | 98.1°F (1991) | 37.9°F (1982) | 1.92 in (2024) |
| August 30 | 99.0°F (1991) | 41.0°F (1986) | 1.21 in (1978) |
| August 31 | 98.1°F (1991) | 43.0°F (1976) | 3.21 in (1975) |