September weather in Poplar, MT
The average temperature in Poplar in September is 56.3°F (40.1°F–72.5°F). Average precipitation: 1.07 inches.
September is a fall month in Poplar, and is warmer than the annual average of 40.5°F. Daily temperatures swing about 32.4°F between overnight low and afternoon high. Expect about 8 days with precipitation. Daylight averages about 12h 20m. For travel, September is a comfortable month to visit.
Avg High
72.5°F
Avg Low
40.1°F
Precipitation
1.07 in
Daylight
12h 20m
September records in Poplar
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 100.9°F (2004) | 34.3°F (2006) | 0.20 in (2008) |
| September 2 | 98.8°F (2015) | 32.5°F (2006) | 0.20 in (2010) |
| September 3 | 99.3°F (2005) | 30.9°F (2008) | 0.17 in (2008) |
| September 4 | 94.8°F (2003) | 32.9°F (2011) | 1.15 in (2007) |
| September 5 | 97.2°F (2022) | 29.5°F (2018) | 0.52 in (2015) |
| September 6 | 97.5°F (2003) | 26.2°F (2025) | 0.35 in (2002) |
| September 7 | 100.6°F (2022) | 26.4°F (2020) | 0.96 in (2019) |
| September 8 | 94.5°F (2024) | 18.7°F (2020) | 0.09 in (2002) |
| September 9 | 99.0°F (2005) | 26.6°F (2020) | 0.41 in (2019) |
| September 10 | 89.8°F (2012) | 30.7°F (2020) | 0.38 in (2006) |
| September 11 | 89.1°F (2017) | 30.0°F (2014) | 0.67 in (2019) |
| September 12 | 88.5°F (2015) | 23.4°F (2014) | 0.59 in (2019) |
| September 13 | 88.2°F (2006) | 19.2°F (2016) | 0.24 in (2008) |
| September 14 | 87.3°F (2009) | 20.1°F (2007) | 0.07 in (2017) |
| September 15 | 92.8°F (2002) | 26.8°F (2007) | 0.70 in (2017) |
| September 16 | 93.4°F (2002) | 29.5°F (2014) | 0.28 in (2015) |
| September 17 | 94.1°F (2024) | 22.5°F (2010) | 1.13 in (2024) |
| September 18 | 98.2°F (2021) | 18.1°F (2010) | 0.14 in (2024) |
| September 19 | 95.0°F (2009) | 24.3°F (2006) | 0.85 in (2019) |
| September 20 | 84.0°F (2025) | 29.8°F (2013) | 1.04 in (2018) |
| September 21 | 88.7°F (2025) | 24.4°F (2004) | 0.53 in (2016) |
| September 22 | 86.4°F (2020) | 21.9°F (2002) | 0.76 in (2006) |
| September 23 | 86.4°F (2011) | 23.9°F (2002) | 0.37 in (2016) |
| September 24 | 90.1°F (2014) | 26.4°F (2007) | 0.26 in (2007) |
| September 25 | 96.4°F (2014) | 23.4°F (2007) | 0.06 in (2018) |
| September 26 | 93.0°F (2015) | 27.0°F (2005) | 0.06 in (2002) |
| September 27 | 90.3°F (2021) | 27.1°F (2018) | 0.11 in (2009) |
| September 28 | 93.6°F (2021) | 19.9°F (2005) | 0.54 in (2019) |
| September 29 | 93.4°F (2024) | 18.9°F (2003) | 0.53 in (2019) |
| September 30 | 91.9°F (2025) | 14.0°F (2003) | 0.36 in (2014) |