September weather in Idaho Falls, ID
The average temperature in Idaho Falls in September is 60.1°F (45.3°F–74.9°F). Average precipitation: 1.13 inches.
September is a fall month in Idaho Falls, and is warmer than the annual average of 46.5°F. Daily temperatures swing about 29.6°F between overnight low and afternoon high. Expect about 5 days with precipitation. Daylight averages about 12h 17m. For travel, September is a comfortable month to visit.
Avg High
74.9°F
Avg Low
45.3°F
Precipitation
1.13 in
Daylight
12h 17m
September records in Idaho Falls
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 93.9°F (2022) | 34.0°F (1952) | 0.31 in (1970) |
| September 2 | 91.9°F (1987) | 33.1°F (1974) | 0.69 in (1985) |
| September 3 | 98.1°F (2022) | 32.0°F (1964) | 0.36 in (2023) |
| September 4 | 93.9°F (1998) | 30.9°F (1964) | 0.26 in (1995) |
| September 5 | 95.0°F (2020) | 30.0°F (1956) | 0.25 in (1970) |
| September 6 | 97.0°F (2022) | 33.1°F (1956) | 0.39 in (1978) |
| September 7 | 96.1°F (2022) | 30.0°F (2010) | 0.60 in (2002) |
| September 8 | 91.9°F (1977) | 30.9°F (1976) | 0.42 in (1973) |
| September 9 | 90.0°F (1990) | 27.0°F (1962) | 0.56 in (2013) |
| September 10 | 91.0°F (1959) | 30.9°F (1970) | 0.39 in (1969) |
| September 11 | 91.0°F (1959) | 32.0°F (1989) | 0.53 in (1997) |
| September 12 | 93.0°F (1990) | 27.0°F (1988) | 1.73 in (1998) |
| September 13 | 91.0°F (1990) | 28.0°F (2003) | 0.62 in (2001) |
| September 14 | 91.9°F (2000) | 27.0°F (1961) | 0.21 in (1966) |
| September 15 | 95.0°F (1990) | 27.0°F (1970) | 0.70 in (2017) |
| September 16 | 91.0°F (1995) | 28.0°F (1970) | 0.75 in (1996) |
| September 17 | 90.0°F (2014) | 24.1°F (1971) | 0.63 in (2024) |
| September 18 | 89.1°F (1962) | 28.0°F (2003) | 0.77 in (2002) |
| September 19 | 88.0°F (1956) | 28.0°F (1971) | 0.53 in (1961) |
| September 20 | 84.9°F (1966) | 19.0°F (1983) | 0.26 in (1963) |
| September 21 | 87.1°F (1966) | 23.0°F (1983) | 1.13 in (2023) |
| September 22 | 88.0°F (1966) | 24.1°F (1956) | 0.94 in (2022) |
| September 23 | 89.1°F (2001) | 25.0°F (1985) | 0.78 in (2016) |
| September 24 | 89.1°F (2001) | 24.1°F (2000) | 0.61 in (2016) |
| September 25 | 89.1°F (2015) | 21.0°F (1970) | 0.28 in (1955) |
| September 26 | 88.0°F (2015) | 27.0°F (1970) | 0.54 in (1982) |
| September 27 | 87.1°F (2001) | 26.1°F (1964) | 1.06 in (2014) |
| September 28 | 87.1°F (1994) | 21.0°F (1985) | 0.96 in (2014) |
| September 29 | 89.1°F (2024) | 18.0°F (1985) | 0.47 in (1994) |
| September 30 | 88.0°F (1957) | 18.0°F (1985) | 0.86 in (1994) |