September weather in Cahokia Heights, IL
The average temperature in Cahokia Heights in September is 68.9°F (57.1°F–80.7°F). Average precipitation: 3.36 inches.
September is a fall month in Cahokia Heights, and is warmer than the annual average of 56.5°F. Daily temperatures swing about 23.6°F between overnight low and afternoon high. Expect about 9 days with precipitation. Daylight averages about 12h 14m. For travel, September is a comfortable month to visit.
Avg High
80.7°F
Avg Low
57.1°F
Precipitation
3.36 in
Daylight
12h 14m
September records in Cahokia Heights
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 102.0°F (2011) | 45.0°F (2009) | 1.73 in (2014) |
| September 2 | 100.9°F (2011) | 46.0°F (2017) | 0.69 in (2010) |
| September 3 | 100.0°F (2011) | 50.0°F (2009) | 2.24 in (2022) |
| September 4 | 96.1°F (1999) | 46.9°F (1997) | 2.95 in (2008) |
| September 5 | 96.1°F (1998) | 44.1°F (1997) | 1.73 in (2009) |
| September 6 | 96.1°F (1998) | 48.9°F (2003) | 0.60 in (2007) |
| September 7 | 96.1°F (2002) | 44.1°F (2017) | 2.42 in (2018) |
| September 8 | 95.0°F (2002) | 42.1°F (2024) | 4.76 in (2018) |
| September 9 | 97.0°F (2013) | 43.0°F (2024) | 2.39 in (2016) |
| September 10 | 98.1°F (2013) | 45.0°F (2024) | 1.49 in (2016) |
| September 11 | 98.1°F (2013) | 46.9°F (2017) | 0.64 in (2015) |
| September 12 | 93.9°F (2025) | 46.9°F (1997) | 0.74 in (1999) |
| September 13 | 96.1°F (2025) | 46.0°F (2014) | 0.70 in (2005) |
| September 14 | 97.0°F (2025) | 42.1°F (2014) | 3.70 in (2008) |
| September 15 | 93.9°F (2025) | 43.0°F (2007) | 1.84 in (2005) |
| September 16 | 95.0°F (2019) | 42.1°F (2000) | 1.69 in (2016) |
| September 17 | 93.0°F (2018) | 42.1°F (1999) | 1.53 in (2006) |
| September 18 | 95.0°F (2025) | 44.1°F (1999) | 1.17 in (2001) |
| September 19 | 96.1°F (2022) | 42.1°F (2012) | 1.56 in (2005) |
| September 20 | 99.0°F (2017) | 37.9°F (2006) | 0.44 in (2002) |
| September 21 | 97.0°F (2022) | 42.1°F (2000) | 1.60 in (2022) |
| September 22 | 98.1°F (2017) | 37.0°F (1999) | 2.37 in (2024) |
| September 23 | 95.0°F (2017) | 37.9°F (2012) | 1.00 in (2024) |
| September 24 | 95.0°F (2017) | 37.9°F (2012) | 0.28 in (2000) |
| September 25 | 95.0°F (2017) | 35.1°F (2001) | 1.32 in (2005) |
| September 26 | 93.0°F (2017) | 35.1°F (2000) | 1.64 in (2003) |
| September 27 | 91.9°F (1998) | 39.9°F (2000) | 1.67 in (2024) |
| September 28 | 90.0°F (2021) | 39.0°F (2022) | 1.59 in (2005) |
| September 29 | 91.9°F (2019) | 37.9°F (2003) | 0.27 in (2008) |
| September 30 | 91.9°F (2019) | 36.0°F (1999) | 0.23 in (2003) |