Idaho Falls September Weather

Averages and records for weather in Idaho Falls, Idaho in the month of September.
Typical Idaho Falls September Weather
1991–2020
Average daily high 75.1 °F
Average daily low 40.5 °F
Average monthly precipitation 0.9 inches
Idaho Falls September Weather Records
1948–2023
Highest temperature 100 °F September 3, 2022
Lowest temperature 18 °F September 24, 2000
Highest daily low 62 °F September 10, 2017
Lowest daily high 38 °F September 17, 1965
Hottest average temperature 6.7 °F
above average
1990
Coldest average temperature -7.7 °F
below average
1965
Most daily precipitation 1.0 inches September 21, 2006
Most monthly precipitation 2.9 inches 2017
Note: Daily averages are a moving average which includes 14 days before and after
Day Average (°F) Record (°F)
High Low High Low
September 1 80.6 44.1 96 32
September 2 80.3 43.9 96 33
September 3 79.9 43.8 100 30
September 4 79.4 43.5 97 31
September 5 79.0 43.2 97 33
September 6 78.5 43.0 99 31
September 7 78.1 42.7 99 30
September 8 77.7 42.4 92 29
September 9 77.2 42.1 95 26
September 10 76.9 41.9 95 29
September 11 76.5 41.6 93 32
September 12 76.1 41.4 91 24
September 13 75.7 41.1 91 29
September 14 75.4 40.8 94 28
September 15 75.2 40.5 91 26
September 16 74.9 40.3 89 29
September 17 74.5 40.1 90 24
September 18 74.0 39.9 90 21
September 19 73.5 39.7 90 22
September 20 72.9 39.4 86 18
September 21 72.4 39.1 86 22
September 22 71.8 38.7 87 25
September 23 71.4 38.4 88 23
September 24 70.9 38.1 88 18
September 25 70.5 37.8 89 21
September 26 69.9 37.5 87 26
September 27 69.4 37.1 86 24
September 28 68.8 36.8 87 18
September 29 68.3 36.5 89 18
September 30 67.8 36.3 90 18
Weather Station Details
Years Station Coordinates
1948–2023 Idaho Falls Fanning Field location