September weather in Mason, WI
The average temperature in Mason in September is 57.4°F (45.8°F–69.0°F). Average precipitation: 3.03 inches.
September is a fall month in Mason, and is warmer than the annual average of 41.5°F. Daily temperatures swing about 23.2°F between overnight low and afternoon high. Expect about 13 days with precipitation. Daylight averages about 12h 19m. For travel, September is a comfortable month to visit.
Avg High
69.0°F
Avg Low
45.8°F
Precipitation
3.03 in
Daylight
12h 19m
September records in Mason
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 89.1°F (2022) | 37.0°F (2017) | 0.61 in (2014) |
| September 2 | 88.0°F (2008) | 42.1°F (2009) | 1.20 in (2018) |
| September 3 | 91.9°F (2023) | 37.9°F (2022) | 0.37 in (2014) |
| September 4 | 95.0°F (2023) | 33.1°F (2022) | 0.97 in (1999) |
| September 5 | 91.0°F (2007) | 36.0°F (2000) | 1.74 in (2023) |
| September 6 | 88.0°F (2007) | 37.9°F (2025) | 0.52 in (2010) |
| September 7 | 90.0°F (2002) | 39.0°F (2024) | 0.85 in (2001) |
| September 8 | 88.0°F (2002) | 33.1°F (2020) | 0.44 in (2001) |
| September 9 | 87.1°F (2002) | 30.2°F (2020) | 2.00 in (2022) |
| September 10 | 90.0°F (2005) | 31.1°F (2006) | 1.66 in (2014) |
| September 11 | 91.9°F (2005) | 32.0°F (2006) | 0.77 in (2008) |
| September 12 | 87.1°F (2011) | 36.0°F (2007) | 0.97 in (2019) |
| September 13 | 86.0°F (2017) | 35.1°F (2006) | 1.24 in (2005) |
| September 14 | 86.0°F (2017) | 26.2°F (2007) | 0.62 in (2021) |
| September 15 | 86.0°F (2015) | 25.2°F (2007) | 1.09 in (2004) |
| September 16 | 89.1°F (2024) | 27.1°F (2011) | 0.11 in (2010) |
| September 17 | 87.1°F (2024) | 30.2°F (2011) | 0.72 in (2021) |
| September 18 | 87.1°F (2024) | 25.2°F (2020) | 1.94 in (2003) |
| September 19 | 87.1°F (2021) | 28.2°F (2020) | 0.80 in (2005) |
| September 20 | 82.0°F (2021) | 30.9°F (1999) | 1.05 in (2018) |
| September 21 | 82.0°F (2007) | 28.0°F (1999) | 0.33 in (2011) |
| September 22 | 84.9°F (2017) | 32.0°F (2013) | 0.67 in (2006) |
| September 23 | 91.0°F (2017) | 28.9°F (2000) | 2.20 in (2010) |
| September 24 | 89.1°F (2017) | 28.0°F (2000) | 0.82 in (2007) |
| September 25 | 79.0°F (2025) | 28.0°F (2001) | 1.21 in (2017) |
| September 26 | 82.0°F (2008) | 28.2°F (2010) | 0.49 in (2017) |
| September 27 | 86.0°F (2024) | 26.2°F (2012) | 0.28 in (2018) |
| September 28 | 82.0°F (2014) | 27.1°F (2022) | 0.40 in (2009) |
| September 29 | 84.9°F (2025) | 28.0°F (2003) | 0.48 in (2014) |
| September 30 | 80.1°F (2024) | 28.2°F (2015) | 2.06 in (2019) |