Ravalli County Weather in September
Average highs run from 76°F on September 1 to 66°F on September 30, and lows from 44°F to 38°F. Normal precipitation for the month is 1.23 in over about 6 wet days.
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
- 71°F
- Average low
- 42°F
- Precipitation
- 1.23 in
- Snowfall
- 0.4 in
- Record high
- 98°FSep 1, 1967
- Record low
- 10°FSep 7, 1895
- Chance of a freeze
- 69%
- Days of 90°F or more
- 1.3
- Daylight
- 13 h 18 min to 11 h 44 min
- Cloud cover
- 51%
- Humidity
- 60%
- Dew point
- 33°F
- Wind
- 4.5 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Sep 1 | 76°F | 44°F | 98°F 1967 | 28°F 1895 | 20% | 0% |
| Sep 2 | 76°F | 44°F | 98°F 1998 | 29°F 1895 | 20% | 0% |
| Sep 3 | 75°F | 44°F | 94°F 1931 | 28°F 1895 | 20% | 0% |
| Sep 4 | 75°F | 44°F | 94°F 1998 | 24°F 1895 | 20% | 0% |
| Sep 5 | 75°F | 44°F | 95°F 1955 | 19°F 1895 | 20% | 1% |
| Sep 6 | 75°F | 43°F | 94°F 2020 | 17°F 1895 | 20% | 1% |
| Sep 7 | 74°F | 43°F | 98°F 1931 | 10°F 1895 | 20% | 1% |
| Sep 8 | 74°F | 43°F | 94°F 2022 | 21°F 1895 | 21% | 1% |
| Sep 9 | 74°F | 43°F | 92°F 2021 | 28°F 1895 | 21% | 1% |
| Sep 10 | 73°F | 43°F | 95°F 1935 | 28°F 1895 | 21% | 1% |
| Sep 11 | 73°F | 43°F | 95°F 1935 | 27°F 1895 | 21% | 1% |
| Sep 12 | 73°F | 42°F | 92°F 1953 | 20°F 1895 | 21% | 1% |
| Sep 13 | 73°F | 42°F | 93°F 2015 | 20°F 1895 | 21% | 1% |
| Sep 14 | 72°F | 42°F | 90°F 1948 | 19°F 1895 | 21% | 1% |
| Sep 15 | 72°F | 42°F | 92°F 2002 | 22°F 1895 | 21% | 1% |
| Sep 16 | 72°F | 42°F | 87°F 1989 | 21°F 1895 | 21% | 1% |
| Sep 17 | 71°F | 41°F | 92°F 2009 | 19°F 1895 | 21% | 1% |
| Sep 18 | 71°F | 41°F | 90°F 1984 | 24°F 1965 | 21% | 1% |
| Sep 19 | 71°F | 41°F | 90°F 1901 | 27°F 1965 | 21% | 2% |
| Sep 20 | 70°F | 41°F | 87°F 1899 | 19°F 1895 | 21% | 2% |
| Sep 21 | 70°F | 41°F | 94°F 1936 | 16°F 1895 | 21% | 2% |
| Sep 22 | 69°F | 40°F | 89°F 1938 | 16°F 1895 | 21% | 2% |
| Sep 23 | 69°F | 40°F | 87°F 1903 | 17°F 1895 | 21% | 2% |
| Sep 24 | 69°F | 40°F | 91°F 2011 | 18°F 1934 | 21% | 2% |
| Sep 25 | 68°F | 40°F | 94°F 2014 | 25°F 1933 | 21% | 2% |
| Sep 26 | 68°F | 39°F | 90°F 2015 | 21°F 1972 | 21% | 2% |
| Sep 27 | 67°F | 39°F | 90°F 1899 | 25°F 1961 | 21% | 2% |
| Sep 28 | 67°F | 39°F | 87°F 1967 | 25°F 1999 | 21% | 3% |
| Sep 29 | 66°F | 38°F | 89°F 2010 | 21°F 1985 | 21% | 3% |
| Sep 30 | 66°F | 38°F | 86°F 1963 | 18°F 1985 | 21% | 3% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (MDT).
- September 1
- sunrise 6:57 AM, sunset 8:15 PM
- September 30
- sunrise 7:34 AM, sunset 7:18 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00242221 (Darby), public domain. Records: NOAA GHCN-Daily, station USC00243885, 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 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.