August weather in Keystone, SD
The average temperature in Keystone in August is 67.8°F (58.0°F–77.5°F). Average precipitation: 2.29 inches.
August is a summer month in Keystone, and is warmer than the annual average of 45.7°F. Daily temperatures swing about 19.5°F between overnight low and afternoon high. Expect about 11 days with precipitation. Daylight averages about 13h 49m. For travel, August is one of the best months of the year to visit.
Avg High
77.5°F
Avg Low
58.0°F
Precipitation
2.29 in
Daylight
13h 49m
August records in Keystone
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 93.0°F (1988) | 46.0°F (1995) | 1.01 in (1972) |
| August 2 | 91.0°F (2024) | 42.1°F (1978) | 0.94 in (1972) |
| August 3 | 93.0°F (2016) | 42.1°F (1978) | 1.18 in (1988) |
| August 4 | 93.0°F (2001) | 41.0°F (1978) | 1.23 in (1965) |
| August 5 | 93.0°F (1970) | 46.0°F (1992) | 1.60 in (2013) |
| August 6 | 96.1°F (1980) | 48.0°F (1989) | 0.65 in (2013) |
| August 7 | 96.1°F (1975) | 46.9°F (1989) | 1.65 in (1970) |
| August 8 | 95.0°F (1975) | 45.0°F (1966) | 0.64 in (2009) |
| August 9 | 93.9°F (1983) | 45.0°F (1985) | 1.32 in (1996) |
| August 10 | 93.0°F (1983) | 44.1°F (1997) | 1.65 in (1998) |
| August 11 | 98.1°F (1969) | 37.9°F (1968) | 1.43 in (1994) |
| August 12 | 97.0°F (1969) | 41.0°F (1977) | 1.07 in (1966) |
| August 13 | 97.0°F (2007) | 42.1°F (1966) | 0.59 in (1971) |
| August 14 | 98.1°F (1971) | 42.1°F (1979) | 0.54 in (2018) |
| August 15 | 98.1°F (1988) | 45.0°F (1978) | 1.95 in (1996) |
| August 16 | 97.0°F (1988) | 45.0°F (1968) | 0.32 in (1976) |
| August 17 | 95.0°F (1970) | 39.9°F (1968) | 1.20 in (2015) |
| August 18 | 93.9°F (1976) | 33.1°F (1968) | 1.06 in (1968) |
| August 19 | 96.1°F (1986) | 37.9°F (2006) | 1.72 in (1966) |
| August 20 | 99.0°F (1973) | 45.0°F (1980) | 0.59 in (2006) |
| August 21 | 91.9°F (1978) | 42.1°F (1964) | 0.49 in (1966) |
| August 22 | 95.0°F (2010) | 35.1°F (1966) | 0.55 in (2007) |
| August 23 | 95.0°F (2020) | 39.9°F (1966) | 0.64 in (1963) |
| August 24 | 96.1°F (1967) | 37.9°F (1992) | 0.31 in (1992) |
| August 25 | 93.9°F (1991) | 37.0°F (2006) | 0.97 in (2022) |
| August 26 | 96.1°F (1970) | 39.0°F (1992) | 1.59 in (2015) |
| August 27 | 95.0°F (2010) | 39.0°F (1964) | 0.87 in (2006) |
| August 28 | 93.0°F (1983) | 44.1°F (2004) | 0.12 in (1982) |
| August 29 | 97.0°F (2012) | 45.0°F (1964) | 2.26 in (1996) |
| August 30 | 93.9°F (1990) | 39.9°F (1994) | 1.07 in (1967) |
| August 31 | 93.9°F (1978) | 37.0°F (1994) | 0.31 in (1980) |