August weather in Rapid City, SD
The average temperature in Rapid City in August is 71.6°F (59.9°F–83.4°F). Average precipitation: 2.17 inches.
August is a summer month in Rapid City, and is warmer than the annual average of 48°F. Daily temperatures swing about 23.5°F between overnight low and afternoon high. Expect about 9 days with precipitation. Daylight averages about 13h 50m. For travel, August is a comfortable month to visit.
Avg High
83.4°F
Avg Low
59.9°F
Precipitation
2.17 in
Daylight
13h 50m
August records in Rapid City
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 99.0°F (2004) | 52.0°F (2009) | 0.95 in (2000) |
| August 2 | 102.0°F (2024) | 54.0°F (1999) | 0.33 in (1997) |
| August 3 | 99.0°F (2024) | 50.0°F (2017) | 1.34 in (2007) |
| August 4 | 100.9°F (2001) | 50.0°F (2017) | 0.57 in (2003) |
| August 5 | 99.0°F (2022) | 52.0°F (2005) | 1.87 in (2014) |
| August 6 | 98.1°F (2001) | 55.0°F (2022) | 0.45 in (2008) |
| August 7 | 100.9°F (2001) | 54.0°F (1996) | 1.67 in (2006) |
| August 8 | 98.1°F (2005) | 53.1°F (2017) | 0.98 in (2016) |
| August 9 | 97.0°F (2007) | 53.1°F (2009) | 0.77 in (2014) |
| August 10 | 99.0°F (2007) | 48.9°F (2004) | 0.97 in (2019) |
| August 11 | 102.0°F (2022) | 45.0°F (2004) | 1.11 in (2019) |
| August 12 | 99.0°F (2020) | 50.0°F (2005) | 0.59 in (2023) |
| August 13 | 100.9°F (2007) | 46.9°F (2004) | 2.01 in (1997) |
| August 14 | 98.1°F (2025) | 48.9°F (2004) | 1.50 in (2017) |
| August 15 | 97.0°F (2003) | 51.1°F (2008) | 0.21 in (2009) |
| August 16 | 98.1°F (2021) | 46.9°F (2002) | 0.06 in (2010) |
| August 17 | 102.9°F (2021) | 45.0°F (2002) | 1.26 in (2015) |
| August 18 | 100.9°F (2023) | 48.9°F (2002) | 0.22 in (1996) |
| August 19 | 96.1°F (2020) | 48.9°F (2004) | 0.69 in (2007) |
| August 20 | 100.0°F (2025) | 50.0°F (2016) | 0.29 in (2021) |
| August 21 | 98.1°F (2008) | 50.0°F (2021) | 0.22 in (2014) |
| August 22 | 100.0°F (2010) | 50.0°F (2009) | 0.59 in (2007) |
| August 23 | 102.0°F (2020) | 46.0°F (2015) | 0.33 in (2018) |
| August 24 | 99.0°F (2000) | 50.0°F (2007) | 0.50 in (2007) |
| August 25 | 99.0°F (2011) | 48.0°F (2014) | 1.49 in (2022) |
| August 26 | 97.0°F (2013) | 51.1°F (2016) | 1.15 in (2016) |
| August 27 | 100.9°F (2013) | 50.0°F (2004) | 0.91 in (2006) |
| August 28 | 98.1°F (2012) | 48.9°F (2004) | 0.63 in (2001) |
| August 29 | 106.0°F (2012) | 48.9°F (2018) | 1.15 in (2011) |
| August 30 | 100.9°F (2015) | 46.9°F (2009) | 1.16 in (2013) |
| August 31 | 97.0°F (2008) | 48.0°F (2010) | 1.15 in (2014) |