Clark Fork Weather in September
Average highs run from 77°F on September 1 to 64°F on September 30, and lows from 43°F to 37°F. Normal precipitation for the month is 1.62 in over about 9 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
- 40°F
- Precipitation
- 1.62 in
- Record high
- 96°FSep 2, 1938
- Record low
- 16°FSep 24, 1926
- Chance of a freeze
- 77%
- Daylight
- 13 h 23 min to 11 h 43 min
- Cloud cover
- 54%
- Humidity
- 57%
- Dew point
- 38°F
- Wind
- 4.3 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 | 77°F | 43°F | 95°F 1938 | 29°F 1930 | 23% | 0% |
| Sep 2 | 77°F | 43°F | 96°F 1938 | 32°F 1914 | 24% | 0% |
| Sep 3 | 76°F | 43°F | 95°F 1938 | 30°F 1932 | 24% | 0% |
| Sep 4 | 76°F | 43°F | 90°F 1988 | 30°F 1912 | 24% | 0% |
| Sep 5 | 75°F | 42°F | 93°F 1998 | 32°F 1912 | 25% | 0% |
| Sep 6 | 75°F | 42°F | 95°F 2025 | 31°F 1992 | 25% | 0% |
| Sep 7 | 75°F | 42°F | 93°F 1998 | 26°F 1929 | 26% | 0% |
| Sep 8 | 74°F | 42°F | 91°F 1944 | 29°F 1976 | 26% | 0% |
| Sep 9 | 74°F | 42°F | 89°F 1944 | 29°F 1932 | 26% | 0% |
| Sep 10 | 74°F | 41°F | 88°F 1944 | 26°F 1921 | 27% | 0% |
| Sep 11 | 73°F | 41°F | 89°F 1973 | 29°F 1928 | 27% | 0% |
| Sep 12 | 73°F | 41°F | 91°F 2011 | 25°F 2014 | 28% | 0% |
| Sep 13 | 72°F | 41°F | 91°F 2011 | 22°F 1921 | 28% | 0% |
| Sep 14 | 72°F | 41°F | 90°F 2013 | 21°F 1970 | 28% | 0% |
| Sep 15 | 71°F | 40°F | 90°F 2013 | 24°F 1970 | 29% | 0% |
| Sep 16 | 71°F | 40°F | 90°F 2013 | 23°F 1973 | 29% | 0% |
| Sep 17 | 71°F | 40°F | 87°F 1938 | 26°F 1971 | 30% | 0% |
| Sep 18 | 70°F | 40°F | 85°F 1952 | 27°F 1971 | 30% | 0% |
| Sep 19 | 70°F | 39°F | 84°F 1984 | 25°F 1957 | 30% | 0% |
| Sep 20 | 69°F | 39°F | 83°F 1967 | 23°F 1928 | 31% | 0% |
| Sep 21 | 69°F | 39°F | 87°F 1938 | 25°F 1932 | 31% | 0% |
| Sep 22 | 68°F | 39°F | 88°F 1987 | 28°F 1946 | 31% | 0% |
| Sep 23 | 68°F | 39°F | 83°F 1987 | 22°F 2000 | 32% | 0% |
| Sep 24 | 67°F | 38°F | 85°F 2011 | 16°F 1926 | 32% | 0% |
| Sep 25 | 67°F | 38°F | 85°F 1990 | 20°F 1926 | 33% | 0% |
| Sep 26 | 66°F | 38°F | 86°F 1952 | 24°F 1926 | 33% | 0% |
| Sep 27 | 66°F | 38°F | 83°F 1994 | 25°F 1961 | 33% | 0% |
| Sep 28 | 65°F | 37°F | 85°F 1994 | 23°F 1984 | 34% | 0% |
| Sep 29 | 64°F | 37°F | 82°F 2006 | 21°F 1919 | 34% | 0% |
| Sep 30 | 64°F | 37°F | 78°F 1990 | 21°F 1929 | 35% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (PDT).
- September 1
- sunrise 6:03 AM, sunset 7:26 PM
- September 30
- sunrise 6:43 AM, sunset 6:26 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00244084 (Heron 2 Nw), public domain. Records: NOAA GHCN-Daily, station USC00108137, 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.