September weather in Monona, WI
The average temperature in Monona in September is 62.3°F (50.7°F–73.9°F). Average precipitation: 3.92 inches.
September is a fall month in Monona, and is warmer than the annual average of 47.2°F. Daily temperatures swing about 23.2°F between overnight low and afternoon high. Expect about 9 days with precipitation. Daylight averages about 12h 17m. For travel, September is one of the best months of the year to visit.
Avg High
73.9°F
Avg Low
50.7°F
Precipitation
3.92 in
Daylight
12h 17m
September records in Monona
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 95.0°F (2013) | 39.9°F (1974) | 2.43 in (1981) |
| September 2 | 93.0°F (2000) | 39.9°F (1994) | 1.31 in (2018) |
| September 3 | 91.0°F (1984) | 37.9°F (1987) | 1.92 in (2010) |
| September 4 | 95.0°F (2023) | 28.9°F (1992) | 1.98 in (2014) |
| September 5 | 93.9°F (1990) | 27.0°F (1983) | 2.05 in (1985) |
| September 6 | 89.1°F (1979) | 30.0°F (1988) | 1.80 in (1983) |
| September 7 | 95.0°F (1990) | 33.1°F (1986) | 0.76 in (2015) |
| September 8 | 96.1°F (1978) | 33.1°F (1986) | 1.69 in (2001) |
| September 9 | 99.0°F (1978) | 32.0°F (1975) | 1.84 in (1985) |
| September 10 | 95.0°F (1978) | 39.0°F (1998) | 1.77 in (2019) |
| September 11 | 95.0°F (2013) | 35.1°F (1995) | 2.29 in (1986) |
| September 12 | 91.9°F (1998) | 34.0°F (1975) | 2.34 in (2022) |
| September 13 | 90.0°F (1990) | 30.9°F (1975) | 2.11 in (2021) |
| September 14 | 91.0°F (1998) | 33.1°F (1975) | 3.36 in (2003) |
| September 15 | 89.1°F (1994) | 32.0°F (2007) | 1.68 in (1998) |
| September 16 | 89.1°F (1994) | 28.9°F (1984) | 1.05 in (1983) |
| September 17 | 88.0°F (2018) | 34.0°F (1984) | 1.55 in (1992) |
| September 18 | 91.0°F (1988) | 35.1°F (1974) | 3.06 in (1978) |
| September 19 | 86.0°F (1988) | 28.9°F (1979) | 0.71 in (2002) |
| September 20 | 90.0°F (1978) | 28.0°F (1991) | 1.44 in (2016) |
| September 21 | 90.0°F (2017) | 28.0°F (1991) | 0.87 in (1972) |
| September 22 | 90.0°F (2024) | 23.0°F (1974) | 2.46 in (2024) |
| September 23 | 91.0°F (2017) | 19.9°F (1974) | 2.52 in (2009) |
| September 24 | 91.9°F (2017) | 26.1°F (1989) | 3.50 in (1994) |
| September 25 | 89.1°F (2017) | 28.0°F (1995) | 2.05 in (1984) |
| September 26 | 89.1°F (2017) | 27.0°F (1975) | 1.63 in (2023) |
| September 27 | 88.0°F (1998) | 25.0°F (1991) | 0.93 in (1992) |
| September 28 | 87.1°F (1990) | 24.1°F (1991) | 0.66 in (1999) |
| September 29 | 84.0°F (1983) | 23.0°F (1984) | 1.60 in (2015) |
| September 30 | 89.1°F (2025) | 25.0°F (1984) | 0.39 in (2018) |