September weather in Rock Falls, IL
The average temperature in Rock Falls in September is °F (°F–°F). Average precipitation: 3.72 inches.
September is a fall month in Rock Falls, and is cooler than the annual average of 0°F. Expect about 8 days with precipitation. Daylight averages about 12h 16m.
Avg High
°F
Avg Low
°F
Precipitation
3.72 in
Daylight
12h 16m
September records in Rock Falls
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | — | — | 0.70 in (2018) |
| September 2 | — | — | 1.66 in (2018) |
| September 3 | — | — | 1.79 in (2018) |
| September 4 | — | — | 1.21 in (2011) |
| September 5 | — | — | 2.53 in (2014) |
| September 6 | — | — | 1.39 in (2020) |
| September 7 | — | — | 1.46 in (2001) |
| September 8 | — | — | 2.21 in (2016) |
| September 9 | — | — | 2.45 in (1991) |
| September 10 | — | — | 2.38 in (1992) |
| September 11 | — | — | 0.95 in (2006) |
| September 12 | — | — | 0.89 in (2020) |
| September 13 | — | — | 2.71 in (2008) |
| September 14 | — | — | 1.72 in (2008) |
| September 15 | — | — | 1.82 in (2019) |
| September 16 | — | — | 0.71 in (2013) |
| September 17 | — | — | 0.96 in (1997) |
| September 18 | — | — | 1.84 in (2015) |
| September 19 | — | — | 1.33 in (2001) |
| September 20 | — | — | 0.40 in (2018) |
| September 21 | — | — | 0.71 in (2000) |
| September 22 | — | — | 0.78 in (2009) |
| September 23 | — | — | 1.28 in (2000) |
| September 24 | — | — | 0.65 in (1994) |
| September 25 | — | — | 1.76 in (2005) |
| September 26 | — | — | 1.66 in (1993) |
| September 27 | — | — | 1.33 in (1996) |
| September 28 | — | — | 3.01 in (1999) |
| September 29 | — | — | 0.73 in (1999) |
| September 30 | — | — | 0.57 in (2008) |