September weather in Monticello, UT
The average temperature in Monticello in September is 59.9°F (46.2°F–73.6°F). Average precipitation: 1.67 inches.
September is a fall month in Monticello, and is warmer than the annual average of 47.3°F. Daily temperatures swing about 27.4°F between overnight low and afternoon high. Daylight averages about 12h 14m. For travel, September is a comfortable month to visit.
Avg High
73.6°F
Avg Low
46.2°F
Precipitation
1.67 in
Daylight
12h 14m
September records in Monticello
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 87.1°F (2019) | 46.0°F (2014) | 1.11 in (2015) |
| September 2 | 90.0°F (2019) | 43.0°F (2018) | 0.53 in (2021) |
| September 3 | 90.0°F (2022) | 48.0°F (2018) | 0.31 in (2021) |
| September 4 | 90.0°F (2017) | 45.0°F (2016) | 0.59 in (2021) |
| September 5 | 91.0°F (2017) | 39.9°F (2016) | 0.56 in (2015) |
| September 6 | 91.0°F (2022) | 41.0°F (2016) | 0.32 in (2014) |
| September 7 | 93.0°F (2022) | 41.0°F (2016) | 0.55 in (2011) |
| September 8 | 89.1°F (2022) | 45.0°F (2016) | 0.21 in (2014) |
| September 9 | 90.0°F (2022) | 28.9°F (2020) | 0.42 in (2014) |
| September 10 | 87.1°F (2021) | 30.9°F (2020) | 0.90 in (2020) |
| September 11 | 84.9°F (2021) | 33.1°F (2020) | 0.62 in (2013) |
| September 12 | 81.0°F (2015) | 37.0°F (2019) | 0.14 in (2012) |
| September 13 | 84.0°F (2015) | 39.0°F (2019) | 0.46 in (2021) |
| September 14 | 81.0°F (2015) | 37.0°F (2025) | 0.21 in (2013) |
| September 15 | 81.0°F (2019) | 36.0°F (2016) | 0.52 in (2023) |
| September 16 | 82.0°F (2021) | 43.0°F (2012) | 0.18 in (2011) |
| September 17 | 79.0°F (2020) | 42.1°F (2017) | 0.15 in (2011) |
| September 18 | 84.9°F (2018) | 36.0°F (2024) | 0.26 in (2011) |
| September 19 | 82.0°F (2018) | 39.9°F (2024) | 0.11 in (2021) |
| September 20 | 79.0°F (2016) | 41.0°F (2011) | 0.09 in (2014) |
| September 21 | 82.9°F (2014) | 39.9°F (2019) | 0.10 in (2016) |
| September 22 | 80.1°F (2015) | 37.0°F (2023) | 0.69 in (2022) |
| September 23 | 78.1°F (2012) | 36.0°F (2016) | 0.49 in (2016) |
| September 24 | 79.0°F (2012) | 33.1°F (2017) | 0.00 in (2011) |
| September 25 | 81.0°F (2015) | 32.0°F (2017) | 0.06 in (2012) |
| September 26 | 80.1°F (2014) | 34.0°F (2017) | 0.14 in (2012) |
| September 27 | 82.9°F (2024) | 36.0°F (2017) | 0.26 in (2025) |
| September 28 | 82.9°F (2024) | 30.9°F (2013) | 1.07 in (2014) |
| September 29 | 82.0°F (2024) | 30.0°F (2013) | 0.33 in (2014) |
| September 30 | 80.1°F (2011) | 35.1°F (2014) | 0.55 in (2016) |