September weather in Mundelein, IL
The average temperature in Mundelein in September is 63.3°F (52.8°F–73.7°F). Average precipitation: 3.38 inches.
September is a fall month in Mundelein, and is warmer than the annual average of 47.9°F. Daily temperatures swing about 20.9°F between overnight low and afternoon high. Expect about 9 days with precipitation. Daylight averages about 12h 16m. For travel, September is one of the best months of the year to visit.
Avg High
73.7°F
Avg Low
52.8°F
Precipitation
3.38 in
Daylight
12h 16m
September records in Mundelein
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 93.9°F (2012) | 43.0°F (2009) | 0.27 in (2019) |
| September 2 | 93.9°F (2000) | 45.0°F (2009) | 2.24 in (2018) |
| September 3 | 93.0°F (2008) | 45.0°F (2017) | 1.78 in (2002) |
| September 4 | 90.0°F (2023) | 48.0°F (2009) | 1.18 in (2018) |
| September 5 | 91.0°F (2012) | 46.0°F (2010) | 3.10 in (2008) |
| September 6 | 90.0°F (2012) | 42.1°F (2000) | 1.07 in (2014) |
| September 7 | 91.0°F (2016) | 44.1°F (2000) | 0.75 in (2001) |
| September 8 | 89.1°F (2003) | 48.0°F (2011) | 1.39 in (2020) |
| September 9 | 91.0°F (2002) | 46.0°F (2008) | 1.41 in (2020) |
| September 10 | 90.0°F (2002) | 42.1°F (2008) | 0.92 in (2014) |
| September 11 | 93.9°F (2013) | 43.0°F (2008) | 0.89 in (2014) |
| September 12 | 89.1°F (2005) | 42.1°F (2007) | 3.53 in (2022) |
| September 13 | 89.1°F (2005) | 39.0°F (2014) | 2.74 in (2019) |
| September 14 | 91.9°F (2005) | 41.0°F (2014) | 1.62 in (2008) |
| September 15 | 86.0°F (2004) | 35.1°F (2007) | 0.96 in (2008) |
| September 16 | 84.9°F (2004) | 36.0°F (2007) | 1.16 in (2013) |
| September 17 | 86.0°F (2017) | 41.0°F (2000) | 1.00 in (2023) |
| September 18 | 89.1°F (2018) | 43.0°F (2014) | 1.47 in (2015) |
| September 19 | 87.1°F (2007) | 37.0°F (2012) | 2.11 in (2001) |
| September 20 | 87.1°F (2021) | 39.9°F (2003) | 0.64 in (2023) |
| September 21 | 90.0°F (2018) | 39.0°F (2006) | 0.72 in (2001) |
| September 22 | 91.0°F (2017) | 39.9°F (2014) | 0.90 in (2019) |
| September 23 | 91.9°F (2017) | 37.0°F (2012) | 1.99 in (2000) |
| September 24 | 91.9°F (2017) | 34.0°F (2012) | 0.62 in (2001) |
| September 25 | 90.0°F (2017) | 37.9°F (2001) | 0.35 in (2022) |
| September 26 | 90.0°F (2017) | 37.9°F (2001) | 1.14 in (2011) |
| September 27 | 89.1°F (2017) | 39.9°F (2012) | 0.68 in (2011) |
| September 28 | 84.9°F (2021) | 39.0°F (2000) | 2.86 in (1999) |
| September 29 | 82.0°F (2013) | 35.1°F (2018) | 1.11 in (1999) |
| September 30 | 84.0°F (2002) | 36.0°F (2018) | 0.42 in (2008) |