September weather in Long Lake, SD
The average temperature in Long Lake in September is 59.1°F (47.1°F–71.0°F). Average precipitation: 2.00 inches.
September is a fall month in Long Lake, and is warmer than the annual average of 41.9°F. Daily temperatures swing about 23.9°F between overnight low and afternoon high. Expect about 8 days with precipitation. Daylight averages about 12h 18m. For travel, September is a comfortable month to visit.
Avg High
71.0°F
Avg Low
47.1°F
Precipitation
2.00 in
Daylight
12h 18m
September records in Long Lake
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 93.6°F (2012) | 47.1°F (2024) | 0.50 in (2008) |
| September 2 | 92.1°F (2023) | 41.4°F (2008) | 0.79 in (2018) |
| September 3 | 96.1°F (2007) | 38.1°F (2008) | 0.05 in (2021) |
| September 4 | 91.4°F (2023) | 38.3°F (2025) | 0.24 in (2016) |
| September 5 | 93.0°F (2007) | 37.6°F (2025) | 0.27 in (2023) |
| September 6 | 90.3°F (2013) | 35.1°F (2025) | 1.30 in (2010) |
| September 7 | 90.3°F (2013) | 38.7°F (2008) | 1.95 in (2019) |
| September 8 | 89.6°F (2022) | 37.4°F (2020) | 1.36 in (2010) |
| September 9 | 83.3°F (2024) | 31.6°F (2020) | 0.78 in (2019) |
| September 10 | 93.7°F (2012) | 36.0°F (2020) | 0.56 in (2010) |
| September 11 | 84.6°F (2011) | 36.0°F (2014) | 0.56 in (2019) |
| September 12 | 95.2°F (2017) | 34.7°F (2014) | 0.45 in (2019) |
| September 13 | 87.6°F (2015) | 30.4°F (2014) | 0.72 in (2024) |
| September 14 | 84.4°F (2022) | 32.7°F (2014) | 0.19 in (2013) |
| September 15 | 87.3°F (2012) | 32.7°F (2007) | 0.49 in (2017) |
| September 16 | 86.0°F (2018) | 36.3°F (2010) | 0.04 in (2016) |
| September 17 | 84.6°F (2019) | 36.3°F (2010) | 0.58 in (2025) |
| September 18 | 88.0°F (2013) | 33.6°F (2010) | 0.96 in (2025) |
| September 19 | 88.0°F (2022) | 35.2°F (2007) | 0.79 in (2025) |
| September 20 | 83.8°F (2019) | 41.5°F (2013) | 1.42 in (2018) |
| September 21 | 90.3°F (2015) | 32.9°F (2012) | 0.59 in (2008) |
| September 22 | 87.1°F (2013) | 23.7°F (2012) | 0.28 in (2023) |
| September 23 | 91.2°F (2007) | 34.5°F (2012) | 1.43 in (2010) |
| September 24 | 80.6°F (2012) | 37.6°F (2021) | 0.81 in (2017) |
| September 25 | 83.3°F (2014) | 36.3°F (2021) | 0.06 in (2017) |
| September 26 | 89.1°F (2024) | 33.8°F (2018) | 0.06 in (2019) |
| September 27 | 83.5°F (2021) | 34.0°F (2018) | 0.17 in (2013) |
| September 28 | 90.1°F (2021) | 27.1°F (2018) | 0.26 in (2013) |
| September 29 | 91.6°F (2024) | 31.6°F (2018) | 0.58 in (2021) |
| September 30 | 82.9°F (2012) | 34.9°F (2018) | 0.34 in (2007) |