September weather in Mount Vernon, MO
The average temperature in Mount Vernon in September is 69.1°F (56.8°F–81.5°F). Average precipitation: 4.70 inches.
September is a fall month in Mount Vernon, and is warmer than the annual average of 56.4°F. Daily temperatures swing about 24.7°F between overnight low and afternoon high. Expect about 8 days with precipitation. Daylight averages about 12h 13m. For travel, September is a comfortable month to visit.
Avg High
81.5°F
Avg Low
56.8°F
Precipitation
4.70 in
Daylight
12h 13m
September records in Mount Vernon
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 104.0°F (2000) | 43.0°F (1967) | 1.10 in (1994) |
| September 2 | 104.0°F (2000) | 52.0°F (1967) | 2.41 in (2010) |
| September 3 | 106.0°F (2000) | 42.1°F (1974) | 1.56 in (1970) |
| September 4 | 102.0°F (2000) | 37.9°F (1974) | 2.35 in (2008) |
| September 5 | 102.0°F (1998) | 42.1°F (1997) | 1.95 in (1973) |
| September 6 | 102.9°F (1998) | 42.1°F (2011) | 3.44 in (1971) |
| September 7 | 100.9°F (1990) | 37.9°F (2011) | 1.79 in (2007) |
| September 8 | 100.9°F (1998) | 37.9°F (2011) | 3.11 in (1970) |
| September 9 | 95.0°F (1980) | 37.9°F (2011) | 4.02 in (1992) |
| September 10 | 95.0°F (2005) | 42.1°F (1976) | 1.33 in (1992) |
| September 11 | 97.0°F (2000) | 39.0°F (1997) | 0.47 in (1975) |
| September 12 | 99.0°F (2000) | 42.1°F (1997) | 1.43 in (2000) |
| September 13 | 93.9°F (1980) | 39.9°F (1996) | 2.88 in (1961) |
| September 14 | 100.0°F (2011) | 41.0°F (1999) | 4.50 in (1993) |
| September 15 | 91.9°F (1960) | 37.9°F (1961) | 3.08 in (2005) |
| September 16 | 93.9°F (1980) | 39.0°F (1979) | 1.62 in (1969) |
| September 17 | 96.1°F (1980) | 37.9°F (1981) | 2.18 in (1986) |
| September 18 | 93.9°F (1960) | 34.0°F (1981) | 2.87 in (2006) |
| September 19 | 91.0°F (2002) | 37.0°F (1991) | 1.45 in (1988) |
| September 20 | 93.0°F (2005) | 37.0°F (1991) | 2.19 in (2009) |
| September 21 | 93.0°F (1980) | 32.0°F (1983) | 2.08 in (1990) |
| September 22 | 93.0°F (1980) | 28.9°F (1995) | 2.79 in (2009) |
| September 23 | 93.0°F (2005) | 28.0°F (1995) | 1.45 in (1970) |
| September 24 | 89.1°F (2005) | 30.0°F (1989) | 2.00 in (1997) |
| September 25 | 86.0°F (1966) | 30.9°F (2001) | 8.20 in (1993) |
| September 26 | 89.1°F (2012) | 33.1°F (2001) | 3.77 in (1996) |
| September 27 | 87.1°F (1981) | 37.0°F (1985) | 1.35 in (1996) |
| September 28 | 90.0°F (1998) | 32.0°F (1967) | 0.71 in (1973) |
| September 29 | 90.0°F (2002) | 30.0°F (1967) | 2.72 in (1977) |
| September 30 | 91.0°F (2002) | 28.9°F (1984) | 5.74 in (1986) |