September weather in Knoxville, TN
The average temperature in Knoxville in September is 70.8°F (58.6°F–82.9°F). Average precipitation: 4.13 inches.
September is a fall month in Knoxville, and is warmer than the annual average of 57.9°F. Daily temperatures swing about 24.3°F between overnight low and afternoon high. Expect about 9 days with precipitation. Daylight averages about 12h 13m. For travel, September is a comfortable month to visit.
Avg High
82.9°F
Avg Low
58.6°F
Precipitation
4.13 in
Daylight
12h 13m
September records in Knoxville
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 96.1°F (2016) | 55.0°F (1976) | 2.37 in (2021) |
| September 2 | 95.0°F (1973) | 52.0°F (2017) | 0.87 in (1986) |
| September 3 | 97.0°F (2011) | 52.0°F (2017) | 1.41 in (1986) |
| September 4 | 97.0°F (2011) | 52.0°F (1997) | 2.16 in (1988) |
| September 5 | 96.1°F (2002) | 48.0°F (1997) | 1.45 in (2011) |
| September 6 | 95.0°F (2016) | 48.9°F (1984) | 4.49 in (2011) |
| September 7 | 96.1°F (2016) | 48.9°F (1984) | 0.86 in (2014) |
| September 8 | 96.1°F (1999) | 48.0°F (2024) | 2.35 in (1977) |
| September 9 | 95.0°F (1999) | 46.0°F (1998) | 1.22 in (1969) |
| September 10 | 95.0°F (2002) | 46.0°F (1998) | 0.58 in (1980) |
| September 11 | 96.1°F (2002) | 42.1°F (1976) | 1.39 in (2015) |
| September 12 | 91.9°F (2019) | 44.1°F (1976) | 2.42 in (2010) |
| September 13 | 93.9°F (2019) | 48.0°F (1993) | 2.20 in (1990) |
| September 14 | 95.0°F (1998) | 43.0°F (1985) | 0.97 in (1973) |
| September 15 | 95.0°F (2016) | 41.0°F (1985) | 2.32 in (1989) |
| September 16 | 95.0°F (2019) | 44.1°F (1984) | 1.65 in (1989) |
| September 17 | 93.0°F (1991) | 43.0°F (1984) | 1.40 in (2009) |
| September 18 | 91.9°F (1991) | 41.0°F (1976) | 6.66 in (2012) |
| September 19 | 91.9°F (1991) | 43.0°F (1973) | 1.15 in (1991) |
| September 20 | 91.9°F (1997) | 44.1°F (1984) | 1.65 in (1969) |
| September 21 | 93.9°F (2024) | 37.9°F (1983) | 1.70 in (2002) |
| September 22 | 93.0°F (2022) | 39.0°F (1983) | 2.14 in (2002) |
| September 23 | 93.9°F (2024) | 37.0°F (1983) | 1.81 in (2003) |
| September 24 | 91.0°F (2016) | 39.9°F (1999) | 5.15 in (2006) |
| September 25 | 91.9°F (2016) | 41.0°F (1990) | 2.64 in (2020) |
| September 26 | 90.0°F (2016) | 39.0°F (2001) | 2.51 in (2024) |
| September 27 | 93.0°F (1993) | 37.9°F (1991) | 3.05 in (2009) |
| September 28 | 91.9°F (2019) | 39.0°F (1985) | 2.37 in (2018) |
| September 29 | 95.0°F (2019) | 39.9°F (1985) | 0.93 in (1996) |
| September 30 | 93.0°F (2019) | 37.0°F (1993) | 1.35 in (1972) |