September weather in Danbury, CT
The average temperature in Danbury in September is 62.9°F (52.3°F–73.6°F). Average precipitation: 4.81 inches.
September is a fall month in Danbury, and is warmer than the annual average of 49.6°F. Daily temperatures swing about 21.3°F between overnight low and afternoon high. Expect about 14 days with precipitation. Daylight averages about 12h 16m. For travel, September is a comfortable month to visit.
Avg High
73.6°F
Avg Low
52.3°F
Precipitation
4.81 in
Daylight
12h 16m
September records in Danbury
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 90.0°F (2010) | 45.0°F (2009) | 2.14 in (2021) |
| September 2 | 90.0°F (2010) | 39.9°F (2017) | 2.51 in (2021) |
| September 3 | 89.1°F (2015) | 46.0°F (2024) | 0.79 in (2017) |
| September 4 | 90.0°F (2022) | 46.9°F (2024) | 0.84 in (2002) |
| September 5 | 91.0°F (2023) | 44.1°F (2000) | 3.15 in (2022) |
| September 6 | 91.0°F (2018) | 39.9°F (2000) | 5.22 in (2008) |
| September 7 | 93.0°F (2023) | 41.0°F (2000) | 0.71 in (1998) |
| September 8 | 93.9°F (2015) | 45.0°F (2025) | 2.83 in (2011) |
| September 9 | 89.1°F (2015) | 42.1°F (2013) | 1.05 in (2023) |
| September 10 | 86.0°F (2016) | 44.1°F (1998) | 2.03 in (1999) |
| September 11 | 91.9°F (2013) | 43.0°F (1998) | 2.85 in (2023) |
| September 12 | 89.1°F (2005) | 37.9°F (2006) | 0.89 in (2013) |
| September 13 | 88.0°F (2005) | 43.0°F (2002) | 1.61 in (2023) |
| September 14 | 86.0°F (2016) | 45.0°F (2014) | 1.94 in (2003) |
| September 15 | 86.0°F (2021) | 39.9°F (2001) | 0.99 in (2006) |
| September 16 | 84.9°F (2015) | 37.9°F (2007) | 9.66 in (1999) |
| September 17 | 84.9°F (2015) | 36.0°F (2007) | 0.13 in (2005) |
| September 18 | 84.0°F (2021) | 37.0°F (2013) | 3.22 in (2004) |
| September 19 | 84.9°F (2022) | 36.0°F (2019) | 1.83 in (2000) |
| September 20 | 82.0°F (2007) | 36.0°F (2020) | 1.01 in (2001) |
| September 21 | 84.9°F (2019) | 32.0°F (2020) | 1.13 in (1999) |
| September 22 | 86.0°F (2019) | 32.0°F (2020) | 1.71 in (1998) |
| September 23 | 89.1°F (2019) | 39.0°F (1998) | 2.61 in (2021) |
| September 24 | 90.0°F (2017) | 35.1°F (1998) | 1.67 in (2021) |
| September 25 | 89.1°F (2017) | 37.9°F (2016) | 2.71 in (2018) |
| September 26 | 90.0°F (2007) | 35.1°F (2016) | 1.64 in (2008) |
| September 27 | 87.1°F (2017) | 35.1°F (2000) | 0.95 in (2002) |
| September 28 | 84.9°F (2025) | 35.1°F (2000) | 2.14 in (2004) |
| September 29 | 82.0°F (2015) | 28.9°F (2000) | 4.34 in (2023) |
| September 30 | 81.0°F (2025) | 32.0°F (2000) | 2.74 in (2010) |