August weather in St. Marys, PA
The average temperature in St. Marys in August is 65.5°F (53.7°F–77.4°F). Average precipitation: 4.25 inches.
August is a summer month in St. Marys, and is warmer than the annual average of 45.1°F. Daily temperatures swing about 23.7°F between overnight low and afternoon high. Expect about 12 days with precipitation. Daylight averages about 13h 40m. For travel, August is a comfortable month to visit.
Avg High
77.4°F
Avg Low
53.7°F
Precipitation
4.25 in
Daylight
13h 40m
August records in St. Marys
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| August 1 | 88.0°F (2024) | 45.0°F (1966) | 3.69 in (1949) |
| August 2 | 91.0°F (2024) | 45.0°F (1966) | 1.80 in (1965) |
| August 3 | 89.1°F (2006) | 42.1°F (1966) | 1.29 in (1961) |
| August 4 | 88.0°F (2012) | 39.9°F (1966) | 2.10 in (2014) |
| August 5 | 88.0°F (2005) | 45.0°F (1970) | 1.21 in (1953) |
| August 6 | 87.1°F (2024) | 43.0°F (2004) | 1.80 in (2022) |
| August 7 | 86.0°F (2018) | 42.1°F (2004) | 2.30 in (1985) |
| August 8 | 86.0°F (2018) | 42.1°F (2004) | 2.90 in (1960) |
| August 9 | 88.0°F (2007) | 46.0°F (2006) | 1.59 in (1953) |
| August 10 | 86.0°F (1973) | 46.9°F (2006) | 2.44 in (1953) |
| August 11 | 88.0°F (2010) | 46.9°F (2019) | 1.26 in (2015) |
| August 12 | 87.1°F (2016) | 44.1°F (2006) | 0.91 in (2014) |
| August 13 | 87.1°F (2005) | 42.1°F (2022) | 1.89 in (2023) |
| August 14 | 89.1°F (2005) | 42.1°F (2022) | 4.34 in (1994) |
| August 15 | 89.1°F (2005) | 41.0°F (2013) | 1.24 in (1973) |
| August 16 | 86.0°F (2024) | 42.1°F (2013) | 1.34 in (1997) |
| August 17 | 84.9°F (2009) | 43.0°F (2014) | 1.51 in (1966) |
| August 18 | 86.0°F (2009) | 42.1°F (2013) | 1.79 in (1949) |
| August 19 | 86.0°F (2009) | 45.0°F (2007) | 1.62 in (2021) |
| August 20 | 84.0°F (2022) | 43.0°F (2008) | 0.88 in (1957) |
| August 21 | 84.0°F (2016) | 41.0°F (2024) | 1.78 in (2004) |
| August 22 | 82.9°F (2003) | 41.0°F (2024) | 1.70 in (2018) |
| August 23 | 86.0°F (2020) | 42.1°F (2024) | 2.19 in (1959) |
| August 24 | 82.9°F (2008) | 41.0°F (2013) | 1.46 in (1988) |
| August 25 | 87.1°F (2007) | 41.0°F (1966) | 0.99 in (2011) |
| August 26 | 86.0°F (2007) | 43.0°F (1966) | 0.48 in (1961) |
| August 27 | 88.0°F (2024) | 45.0°F (2010) | 1.84 in (1987) |
| August 28 | 89.1°F (2024) | 45.0°F (2015) | 2.42 in (2006) |
| August 29 | 91.0°F (1973) | 43.0°F (2011) | 1.45 in (1992) |
| August 30 | 87.1°F (1973) | 43.0°F (2014) | 1.85 in (1975) |
| August 31 | 88.0°F (1973) | 45.0°F (2003) | 2.32 in (1970) |