September weather in Basco, IL
The average temperature in Basco in September is 67.2°F (55.5°F–78.8°F). Average precipitation: 3.67 inches.
September is a fall month in Basco, and is warmer than the annual average of 52.8°F. Daily temperatures swing about 23.3°F between overnight low and afternoon high. Expect about 7 days with precipitation. Daylight averages about 12h 15m. For travel, September is one of the best months of the year to visit.
Avg High
78.8°F
Avg Low
55.5°F
Precipitation
3.67 in
Daylight
12h 15m
September records in Basco
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 100.9°F (2011) | 46.9°F (2009) | 3.06 in (2003) |
| September 2 | 104.0°F (2011) | 48.0°F (2009) | 2.03 in (1993) |
| September 3 | 104.0°F (2011) | 48.9°F (2009) | 1.04 in (1961) |
| September 4 | 102.0°F (2011) | 44.1°F (1997) | 1.30 in (1953) |
| September 5 | 98.1°F (2018) | 46.0°F (1997) | 0.91 in (1971) |
| September 6 | 93.0°F (1998) | 43.0°F (2025) | 3.42 in (2018) |
| September 7 | 93.9°F (1998) | 45.0°F (2011) | 2.30 in (1995) |
| September 8 | 95.0°F (2013) | 43.0°F (2024) | 2.57 in (1992) |
| September 9 | 98.1°F (2000) | 44.1°F (1998) | 1.75 in (1992) |
| September 10 | 102.0°F (2013) | 44.1°F (2008) | 4.72 in (2014) |
| September 11 | 98.1°F (2013) | 45.0°F (1995) | 1.65 in (1986) |
| September 12 | 98.1°F (2013) | 41.0°F (2007) | 2.46 in (2020) |
| September 13 | 93.9°F (1998) | 39.0°F (2014) | 3.00 in (1961) |
| September 14 | 98.1°F (2025) | 37.9°F (1996) | 2.29 in (1998) |
| September 15 | 98.1°F (2025) | 36.0°F (2007) | 2.08 in (1981) |
| September 16 | 91.9°F (2025) | 37.9°F (2011) | 3.16 in (2004) |
| September 17 | 95.0°F (1997) | 43.0°F (1999) | 2.23 in (1982) |
| September 18 | 91.9°F (2015) | 42.1°F (1995) | 2.62 in (2022) |
| September 19 | 93.9°F (2007) | 42.1°F (2020) | 2.42 in (2022) |
| September 20 | 93.9°F (2007) | 36.0°F (2006) | 1.61 in (2013) |
| September 21 | 97.0°F (2022) | 36.0°F (2006) | 1.35 in (1957) |
| September 22 | 93.0°F (2007) | 30.9°F (1995) | 3.36 in (1970) |
| September 23 | 93.0°F (2017) | 28.9°F (1995) | 3.68 in (1961) |
| September 24 | 93.9°F (2007) | 34.0°F (1995) | 1.53 in (1970) |
| September 25 | 91.9°F (2007) | 37.9°F (2001) | 1.49 in (1993) |
| September 26 | 91.9°F (2007) | 39.0°F (2000) | 1.43 in (1996) |
| September 27 | 89.1°F (1998) | 39.9°F (2000) | 1.15 in (1955) |
| September 28 | 91.9°F (2021) | 39.0°F (2022) | 3.82 in (1999) |
| September 29 | 90.0°F (2025) | 33.1°F (2003) | 2.66 in (1986) |
| September 30 | 91.9°F (2002) | 36.0°F (2003) | 0.82 in (1978) |