September weather in Aliquippa, PA
The average temperature in Aliquippa in September is 65.8°F (55.9°F–75.7°F). Average precipitation: 3.45 inches.
September is a fall month in Aliquippa, and is warmer than the annual average of 51.7°F. Daily temperatures swing about 19.8°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
75.7°F
Avg Low
55.9°F
Precipitation
3.45 in
Daylight
12h 15m
September records in Aliquippa
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 95.0°F (2012) | 50.0°F (2025) | 1.90 in (1965) |
| September 2 | 91.0°F (2015) | 52.0°F (2025) | 3.03 in (2019) |
| September 3 | 96.1°F (2011) | 51.1°F (2024) | 1.01 in (1993) |
| September 4 | 97.0°F (2011) | 50.0°F (2024) | 0.97 in (1981) |
| September 5 | 90.0°F (2018) | 52.0°F (2024) | 2.57 in (1958) |
| September 6 | 93.0°F (2015) | 54.0°F (2013) | 1.53 in (2022) |
| September 7 | 90.0°F (2015) | 54.0°F (2013) | 1.90 in (1990) |
| September 8 | 91.0°F (2015) | 46.9°F (2025) | 0.50 in (1998) |
| September 9 | 93.9°F (2016) | 46.0°F (2025) | 4.57 in (2004) |
| September 10 | 91.0°F (2015) | 48.0°F (2017) | 3.05 in (2018) |
| September 11 | 93.0°F (2013) | 46.9°F (2012) | 1.04 in (1968) |
| September 12 | 88.0°F (2013) | 46.0°F (2012) | 1.82 in (1950) |
| September 13 | 87.1°F (2021) | 48.9°F (2012) | 2.37 in (1972) |
| September 14 | 84.9°F (2011) | 48.9°F (2014) | 1.87 in (1972) |
| September 15 | 86.0°F (2021) | 48.9°F (2014) | 0.50 in (1989) |
| September 16 | 84.9°F (2024) | 46.0°F (2011) | 0.77 in (1952) |
| September 17 | 84.0°F (2016) | 46.0°F (2011) | 1.19 in (1994) |
| September 18 | 84.0°F (2021) | 48.9°F (2012) | 7.00 in (2004) |
| September 19 | 84.0°F (2025) | 43.0°F (2020) | 1.30 in (1954) |
| September 20 | 84.9°F (2025) | 42.1°F (2020) | 1.56 in (1953) |
| September 21 | 84.9°F (2018) | 43.0°F (2020) | 1.37 in (1957) |
| September 22 | 88.0°F (2018) | 43.0°F (2020) | 0.88 in (1979) |
| September 23 | 93.0°F (2017) | 43.0°F (2020) | 1.37 in (2025) |
| September 24 | 93.0°F (2017) | 46.9°F (2014) | 1.80 in (1975) |
| September 25 | 91.9°F (2017) | 48.0°F (2012) | 1.17 in (2001) |
| September 26 | 91.0°F (2017) | 48.9°F (2013) | 0.90 in (1945) |
| September 27 | 93.0°F (2017) | 51.1°F (2019) | 1.69 in (2002) |
| September 28 | 81.0°F (2013) | 46.0°F (2022) | 1.40 in (2012) |
| September 29 | 84.9°F (2025) | 46.0°F (2022) | 1.43 in (1979) |
| September 30 | 82.9°F (2025) | 44.1°F (2022) | 2.10 in (2015) |