September weather in Alamosa, CO
The average temperature in Alamosa in September is 56.0°F (37.1°F–74.9°F). Average precipitation: 0.94 inches.
September is a fall month in Alamosa, and is warmer than the annual average of 42.6°F. Daily temperatures swing about 37.8°F between overnight low and afternoon high. Expect about 7 days with precipitation. Daylight averages about 12h 14m. For travel, September is cool.
Avg High
74.9°F
Avg Low
37.1°F
Precipitation
0.94 in
Daylight
12h 14m
September records in Alamosa
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 87.1°F (2011) | 30.9°F (2010) | 0.23 in (2011) |
| September 2 | 87.1°F (2023) | 30.9°F (2010) | 0.22 in (2021) |
| September 3 | 86.0°F (2019) | 36.0°F (2024) | 0.15 in (2018) |
| September 4 | 88.0°F (2017) | 32.0°F (2008) | 0.10 in (2007) |
| September 5 | 89.1°F (2020) | 33.1°F (2008) | 0.04 in (2009) |
| September 6 | 89.1°F (2020) | 32.0°F (2008) | 0.37 in (2025) |
| September 7 | 91.0°F (2020) | 30.9°F (2008) | 0.70 in (2005) |
| September 8 | 87.1°F (2020) | 32.0°F (2008) | 0.16 in (2019) |
| September 9 | 88.0°F (2021) | 27.0°F (2020) | 1.39 in (2020) |
| September 10 | 89.1°F (2021) | 27.0°F (2020) | 0.19 in (2005) |
| September 11 | 89.1°F (2021) | 28.9°F (2010) | 0.32 in (2013) |
| September 12 | 89.1°F (2021) | 30.0°F (2010) | 0.20 in (2023) |
| September 13 | 84.9°F (2021) | 27.0°F (2008) | 0.74 in (2012) |
| September 14 | 86.0°F (2018) | 28.0°F (2005) | 0.41 in (2023) |
| September 15 | 82.0°F (2018) | 25.0°F (2005) | 0.54 in (2013) |
| September 16 | 84.0°F (2018) | 25.0°F (2005) | 0.28 in (2019) |
| September 17 | 84.0°F (2018) | 28.0°F (2008) | 0.16 in (2024) |
| September 18 | 84.0°F (2018) | 25.0°F (2012) | 0.28 in (2007) |
| September 19 | 84.9°F (2018) | 24.1°F (2005) | 0.14 in (2013) |
| September 20 | 84.0°F (2010) | 28.0°F (2005) | 0.42 in (2018) |
| September 21 | 84.0°F (2014) | 28.0°F (2012) | 0.28 in (2009) |
| September 22 | 81.0°F (2020) | 23.0°F (2009) | 0.63 in (2024) |
| September 23 | 80.1°F (2012) | 25.0°F (2009) | 0.98 in (2013) |
| September 24 | 81.0°F (2021) | 23.0°F (2008) | 0.12 in (2017) |
| September 25 | 80.1°F (2020) | 21.9°F (2007) | 0.02 in (2012) |
| September 26 | 82.9°F (2020) | 21.9°F (2007) | 0.02 in (2012) |
| September 27 | 84.0°F (2020) | 27.0°F (2007) | 0.06 in (2017) |
| September 28 | 87.1°F (2020) | 19.9°F (2013) | 0.86 in (2017) |
| September 29 | 82.9°F (2010) | 25.0°F (2020) | 0.37 in (2014) |
| September 30 | 84.0°F (2010) | 24.1°F (2020) | 0.27 in (2014) |