September weather in Monongahela, PA
The average temperature in Monongahela in September is 66.9°F (55.9°F–77.8°F). Average precipitation: 3.26 inches.
September is a fall month in Monongahela, and is warmer than the annual average of 52.9°F. Daily temperatures swing about 21.9°F between overnight low and afternoon high. Expect about 9 days with precipitation. Daylight averages about 12h 15m. For travel, September is one of the best months of the year to visit.
Avg High
77.8°F
Avg Low
55.9°F
Precipitation
3.26 in
Daylight
12h 15m
September records in Monongahela
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 91.9°F (2012) | 50.0°F (2025) | 1.72 in (2021) |
| September 2 | 91.9°F (2015) | 51.1°F (2025) | 1.68 in (2012) |
| September 3 | 91.0°F (2018) | 50.0°F (2024) | 1.42 in (1962) |
| September 4 | 95.0°F (2011) | 50.0°F (2024) | 2.17 in (1993) |
| September 5 | 95.0°F (2018) | 51.1°F (2024) | 2.11 in (1937) |
| September 6 | 95.0°F (2018) | 51.1°F (2013) | 1.00 in (1941) |
| September 7 | 93.0°F (2023) | 51.1°F (2013) | 1.78 in (1990) |
| September 8 | 87.1°F (2016) | 45.0°F (2025) | 0.81 in (1938) |
| September 9 | 89.1°F (2020) | 45.0°F (2025) | 2.50 in (2018) |
| September 10 | 88.0°F (2020) | 46.0°F (2024) | 4.38 in (2018) |
| September 11 | 89.1°F (2016) | 41.0°F (2012) | 2.10 in (2018) |
| September 12 | 93.9°F (2019) | 48.9°F (2017) | 1.54 in (1960) |
| September 13 | 90.0°F (2019) | 51.1°F (2025) | 1.85 in (1938) |
| September 14 | 89.1°F (2018) | 48.9°F (2014) | 1.04 in (1951) |
| September 15 | 84.9°F (2018) | 48.9°F (2013) | 1.19 in (1990) |
| September 16 | 88.0°F (2024) | 42.1°F (2011) | 1.18 in (1952) |
| September 17 | 88.0°F (2015) | 42.1°F (2011) | 1.34 in (1996) |
| September 18 | 89.1°F (2015) | 48.0°F (2012) | 3.23 in (2004) |
| September 19 | 89.1°F (2021) | 43.0°F (2020) | 1.11 in (2012) |
| September 20 | 87.1°F (2025) | 37.9°F (2020) | 1.87 in (1953) |
| September 21 | 89.1°F (2024) | 37.9°F (2020) | 1.67 in (1961) |
| September 22 | 90.0°F (2018) | 43.0°F (2020) | 2.30 in (1950) |
| September 23 | 90.0°F (2019) | 43.0°F (2020) | 1.33 in (1932) |
| September 24 | 89.1°F (2016) | 44.1°F (2022) | 1.70 in (1975) |
| September 25 | 91.0°F (2017) | 44.1°F (2022) | 1.20 in (1986) |
| September 26 | 89.1°F (2017) | 45.0°F (2012) | 1.68 in (1977) |
| September 27 | 90.0°F (2017) | 48.9°F (2021) | 1.88 in (2002) |
| September 28 | 90.0°F (2017) | 45.0°F (2022) | 1.23 in (2010) |
| September 29 | 88.0°F (2019) | 45.0°F (2022) | 1.74 in (1979) |
| September 30 | 82.0°F (2019) | 42.1°F (2022) | 1.72 in (2015) |