September weather in Hermantown, MN
The average temperature in Hermantown in September is 56.7°F (47.3°F–66.1°F). Average precipitation: 3.50 inches.
September is a fall month in Hermantown, and is warmer than the annual average of 39.7°F. Daily temperatures swing about 18.8°F between overnight low and afternoon high. Daylight averages about 12h 19m. For travel, September is a comfortable month to visit.
Avg High
66.1°F
Avg Low
47.3°F
Precipitation
3.50 in
Daylight
12h 19m
September records in Hermantown
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 81.0°F (2012) | 46.0°F (2019) | 0.86 in (2018) |
| September 2 | 84.0°F (2015) | 46.9°F (2020) | 0.64 in (2025) |
| September 3 | 88.0°F (2023) | 41.0°F (2025) | 1.12 in (2015) |
| September 4 | 93.9°F (2023) | 39.9°F (2025) | 0.46 in (2025) |
| September 5 | 90.0°F (2023) | 39.9°F (2025) | 0.18 in (2018) |
| September 6 | 86.0°F (2023) | 37.9°F (2025) | 2.17 in (2023) |
| September 7 | 84.9°F (2013) | 36.0°F (2024) | 1.31 in (2015) |
| September 8 | 82.0°F (2013) | 41.0°F (2020) | 0.84 in (2016) |
| September 9 | 80.1°F (2022) | 35.1°F (2020) | 0.15 in (2025) |
| September 10 | 75.0°F (2014) | 36.0°F (2020) | 1.37 in (2019) |
| September 11 | 81.0°F (2024) | 35.1°F (2020) | 0.22 in (2014) |
| September 12 | 82.0°F (2012) | 37.0°F (2014) | 0.69 in (2023) |
| September 13 | 75.0°F (2018) | 33.1°F (2014) | 0.98 in (2019) |
| September 14 | 77.0°F (2018) | 33.1°F (2014) | 0.24 in (2021) |
| September 15 | 80.1°F (2024) | 39.0°F (2016) | 1.07 in (2021) |
| September 16 | 84.0°F (2024) | 39.0°F (2013) | 1.74 in (2018) |
| September 17 | 82.0°F (2024) | 34.0°F (2013) | 0.66 in (2021) |
| September 18 | 82.9°F (2024) | 32.0°F (2020) | 1.12 in (2015) |
| September 19 | 79.0°F (2024) | 30.0°F (2020) | 0.36 in (2025) |
| September 20 | 82.9°F (2021) | 39.9°F (2020) | 0.30 in (2012) |
| September 21 | 81.0°F (2022) | 43.0°F (2012) | 0.77 in (2018) |
| September 22 | 79.0°F (2023) | 32.0°F (2012) | 0.23 in (2012) |
| September 23 | 81.0°F (2020) | 32.0°F (2012) | 0.06 in (2023) |
| September 24 | 82.0°F (2020) | 30.9°F (2012) | 1.42 in (2015) |
| September 25 | 78.1°F (2025) | 39.9°F (2012) | 2.66 in (2023) |
| September 26 | 81.0°F (2024) | 34.0°F (2012) | 0.61 in (2016) |
| September 27 | 82.0°F (2024) | 33.1°F (2012) | 0.18 in (2016) |
| September 28 | 82.9°F (2024) | 32.0°F (2022) | 0.25 in (2018) |
| September 29 | 81.0°F (2025) | 30.9°F (2022) | 0.37 in (2013) |
| September 30 | 78.1°F (2024) | 28.9°F (2018) | 0.12 in (2014) |