Mountain Home Weather in September
Average highs run from 88°F on September 1 to 76°F on September 30, and lows from 53°F to 43°F.
September day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
September at a glance
- Average high
- 82°F
- Average low
- 48°F
- Record high
- 103°FSep 1, 1987
- Record low
- 21°FSep 18, 1965
- Chance of a freeze
- 26%
- Days of 90°F or more
- 7.4
- Daylight
- 13 h 10 min to 11 h 46 min
- Cloud cover
- 36%
- Humidity
- 32%
- Dew point
- 33°F
- Wind
- 7.4 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation.
| Date | Normal high | Normal low | Record high | Record low | Chance wet |
|---|---|---|---|---|---|
| Sep 1 | 88°F | 53°F | 103°F 1987 | 36°F 1965 | |
| Sep 2 | 87°F | 53°F | 99°F 1978 | 38°F 1975 | |
| Sep 3 | 87°F | 52°F | 103°F 2007 | 38°F 1975 | |
| Sep 4 | 86°F | 52°F | 99°F 1977 | 35°F 1969 | |
| Sep 5 | 86°F | 52°F | 100°F 1976 | 38°F 1940 | |
| Sep 6 | 86°F | 51°F | 102°F 1944 | 36°F 1996 | |
| Sep 7 | 85°F | 51°F | 101°F 1944 | 34°F 1992 | |
| Sep 8 | 85°F | 51°F | 103°F 1944 | 35°F 1941 | |
| Sep 9 | 85°F | 50°F | 97°F 1969 | 34°F 1962 | |
| Sep 10 | 84°F | 50°F | 99°F 1971 | 35°F 1970 | |
| Sep 11 | 84°F | 50°F | 99°F 1990 | 33°F 2005 | |
| Sep 12 | 83°F | 49°F | 103°F 1944 | 34°F 1988 | |
| Sep 13 | 83°F | 49°F | 98°F 1981 | 33°F 1970 | |
| Sep 14 | 83°F | 49°F | 100°F 2000 | 30°F 1970 | |
| Sep 15 | 82°F | 48°F | 99°F 2000 | 31°F 1970 | |
| Sep 16 | 82°F | 48°F | 98°F 1981 | 35°F 1970 | |
| Sep 17 | 81°F | 48°F | 103°F 1981 | 27°F 1965 | |
| Sep 18 | 81°F | 47°F | 99°F 1981 | 21°F 1965 | |
| Sep 19 | 81°F | 47°F | 98°F 1962 | 24°F 1965 | |
| Sep 20 | 80°F | 47°F | 98°F 1962 | 31°F 2004 | |
| Sep 21 | 80°F | 46°F | 98°F 1962 | 27°F 1983 | |
| Sep 22 | 79°F | 46°F | 99°F 1966 | 27°F 1995 | |
| Sep 23 | 79°F | 45°F | 99°F 2011 | 29°F 1996 | |
| Sep 24 | 79°F | 45°F | 99°F 2011 | 29°F 2000 | |
| Sep 25 | 78°F | 45°F | 94°F 1989 | 26°F 1970 | |
| Sep 26 | 78°F | 44°F | 94°F 1963 | 31°F 1970 | |
| Sep 27 | 77°F | 44°F | 92°F 1967 | 30°F 1964 | |
| Sep 28 | 77°F | 44°F | 95°F 1963 | 28°F 1999 | |
| Sep 29 | 76°F | 43°F | 95°F 1963 | 28°F 1999 | |
| Sep 30 | 76°F | 43°F | 98°F 1992 | 26°F 1985 |
Chance of rain
Sunrise and sunset
Times for 2026, local time (MDT).
- September 1
- sunrise 7:07 AM, sunset 8:17 PM
- September 30
- sunrise 7:39 AM, sunset 7:25 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00106174 (Mtn Home), public domain. Records: NOAA GHCN-Daily, station USC00101195, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus.