September weather in Mount Morris, MI
The average temperature in Mount Morris in September is 61.4°F (48.4°F–74.4°F). Average precipitation: 2.95 inches.
September is a fall month in Mount Morris, and is warmer than the annual average of 47.2°F. Daily temperatures swing about 26°F between overnight low and afternoon high. Daylight averages about 12h 17m. For travel, September is a comfortable month to visit.
Avg High
74.4°F
Avg Low
48.4°F
Precipitation
2.95 in
Daylight
12h 17m
September records in Mount Morris
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 91.9°F (2012) | 37.9°F (2009) | 0.09 in (2016) |
| September 2 | 90.0°F (2011) | 37.9°F (2017) | 0.97 in (2020) |
| September 3 | 96.1°F (2011) | 37.9°F (2017) | 0.28 in (2019) |
| September 4 | 91.0°F (2011) | 44.1°F (2024) | 0.52 in (2011) |
| September 5 | 91.0°F (2018) | 46.0°F (2024) | 1.03 in (2012) |
| September 6 | 91.9°F (2007) | 41.0°F (2013) | 0.40 in (2014) |
| September 7 | 91.9°F (2016) | 39.0°F (2025) | 0.66 in (2023) |
| September 8 | 91.9°F (2015) | 37.0°F (2025) | 1.78 in (2012) |
| September 9 | 84.9°F (2006) | 35.1°F (2017) | 0.71 in (2020) |
| September 10 | 84.0°F (2016) | 35.1°F (2017) | 0.22 in (2016) |
| September 11 | 93.9°F (2013) | 37.9°F (2017) | 0.83 in (2007) |
| September 12 | 91.0°F (2013) | 41.0°F (2017) | 1.57 in (2019) |
| September 13 | 91.0°F (2005) | 37.0°F (2007) | 1.28 in (2021) |
| September 14 | 91.0°F (2005) | 33.1°F (2013) | 0.74 in (2012) |
| September 15 | 87.1°F (2021) | 33.1°F (2013) | 0.28 in (2021) |
| September 16 | 84.9°F (2024) | 33.1°F (2007) | 0.20 in (2005) |
| September 17 | 84.0°F (2015) | 30.9°F (2013) | 0.39 in (2010) |
| September 18 | 86.0°F (2018) | 30.9°F (2013) | 1.29 in (2016) |
| September 19 | 87.1°F (2025) | 30.9°F (2020) | 0.41 in (2010) |
| September 20 | 88.0°F (2007) | 30.9°F (2020) | 0.67 in (2011) |
| September 21 | 82.9°F (2019) | 35.1°F (2020) | 0.62 in (2014) |
| September 22 | 91.9°F (2017) | 39.0°F (2020) | 1.17 in (2021) |
| September 23 | 91.0°F (2017) | 34.0°F (2013) | 2.92 in (2005) |
| September 24 | 91.9°F (2017) | 32.0°F (2013) | 0.47 in (2021) |
| September 25 | 91.0°F (2017) | 32.0°F (2013) | 0.16 in (2025) |
| September 26 | 90.0°F (2017) | 36.0°F (2006) | 0.65 in (2009) |
| September 27 | 91.0°F (2017) | 37.0°F (2006) | 0.65 in (2022) |
| September 28 | 87.1°F (2025) | 33.1°F (2012) | 0.80 in (2019) |
| September 29 | 79.0°F (2015) | 30.9°F (2009) | 0.57 in (2005) |
| September 30 | 82.0°F (2025) | 33.1°F (2006) | 0.61 in (2016) |