September weather in Gustavus, AK
The average temperature in Gustavus in September is 48.7°F (40.9°F–56.4°F). Average precipitation: 7.64 inches.
September is a fall month in Gustavus, and is warmer than the annual average of 40.7°F. Daily temperatures swing about 15.5°F between overnight low and afternoon high. Daylight averages about 12h 29m. For travel, September is a wet month.
Avg High
56.4°F
Avg Low
40.9°F
Precipitation
7.64 in
Daylight
12h 29m
September records in Gustavus
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 68.7°F (2016) | 32.0°F (2016) | 0.52 in (2020) |
| September 2 | 66.7°F (2016) | 32.9°F (2018) | 0.63 in (2021) |
| September 3 | 72.7°F (2025) | 28.4°F (2017) | 0.47 in (2021) |
| September 4 | 66.7°F (2025) | 30.6°F (2018) | 1.63 in (2017) |
| September 5 | 69.4°F (2018) | 32.4°F (2018) | 0.58 in (2016) |
| September 6 | 68.7°F (2019) | 30.6°F (2019) | 1.08 in (2017) |
| September 7 | 70.3°F (2019) | 29.5°F (2018) | 1.43 in (2012) |
| September 8 | 72.3°F (2019) | 30.6°F (2019) | 0.78 in (2012) |
| September 9 | 70.5°F (2018) | 29.1°F (2019) | 1.72 in (2016) |
| September 10 | 72.0°F (2018) | 32.7°F (2018) | 1.84 in (2025) |
| September 11 | 70.3°F (2018) | 28.4°F (2018) | 0.37 in (2012) |
| September 12 | 65.1°F (2018) | 28.4°F (2018) | 1.58 in (2016) |
| September 13 | 63.3°F (2020) | 31.1°F (2018) | 1.33 in (2012) |
| September 14 | 64.2°F (2018) | 26.4°F (2018) | 1.63 in (2023) |
| September 15 | 65.8°F (2019) | 22.3°F (2018) | 0.33 in (2016) |
| September 16 | 62.2°F (2020) | 18.5°F (2018) | 0.65 in (2019) |
| September 17 | 64.8°F (2019) | 19.6°F (2018) | 1.09 in (2015) |
| September 18 | 62.4°F (2018) | 20.5°F (2018) | 0.63 in (2013) |
| September 19 | 62.1°F (2018) | 19.9°F (2018) | 0.70 in (2014) |
| September 20 | 61.2°F (2018) | 21.0°F (2018) | 2.03 in (2019) |
| September 21 | 61.9°F (2018) | 21.6°F (2018) | 1.20 in (2022) |
| September 22 | 59.9°F (2012) | 25.5°F (2018) | 0.57 in (2016) |
| September 23 | 59.7°F (2012) | 32.4°F (2015) | 1.41 in (2022) |
| September 24 | 65.5°F (2014) | 28.8°F (2013) | 0.65 in (2021) |
| September 25 | 57.0°F (2022) | 26.4°F (2013) | 1.05 in (2018) |
| September 26 | 59.7°F (2022) | 27.3°F (2019) | 1.79 in (2022) |
| September 27 | 60.4°F (2017) | 26.1°F (2019) | 1.34 in (2020) |
| September 28 | 57.9°F (2017) | 23.4°F (2019) | 0.63 in (2020) |
| September 29 | 66.2°F (2018) | 24.1°F (2019) | 0.97 in (2015) |
| September 30 | 66.2°F (2018) | 24.1°F (2018) | 1.21 in (2022) |