Glacier County Weather in September
Average highs run from 69°F on September 1 to 56°F on September 30, and lows from 42°F to 36°F. Normal precipitation for the month is 1.63 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
- 63°F
- Average low
- 39°F
- Precipitation
- 1.63 in
- Record high
- 97°FSep 1, 1967
- Record low
- -4°FSep 25, 1934
- Chance of a freeze
- 95%
- Daylight
- 13 h 25 min to 11 h 43 min
- Cloud cover
- 57%
- Humidity
- 63%
- Dew point
- 36°F
- Wind
- 7.2 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 | 69°F | 42°F | 97°F 1967 | 30°F 1914 | 28% |
| Sep 2 | 68°F | 42°F | 92°F 1969 | 28°F 1956 | 28% |
| Sep 3 | 68°F | 42°F | 96°F 2022 | 24°F 1962 | 28% |
| Sep 4 | 68°F | 42°F | 94°F 2003 | 26°F 1929 | 28% |
| Sep 5 | 67°F | 41°F | 94°F 1967 | 24°F 1956 | 28% |
| Sep 6 | 67°F | 41°F | 91°F 1966 | 18°F 1929 | 28% |
| Sep 7 | 66°F | 41°F | 95°F 2022 | 24°F 1939 | 28% |
| Sep 8 | 66°F | 41°F | 93°F 1981 | 27°F 1943 | 28% |
| Sep 9 | 66°F | 41°F | 90°F 1981 | 26°F 1992 | 29% |
| Sep 10 | 65°F | 40°F | 88°F 1963 | 27°F 1921 | 29% |
| Sep 11 | 65°F | 40°F | 90°F 1981 | 24°F 1949 | 29% |
| Sep 12 | 64°F | 40°F | 88°F 1953 | 20°F 1949 | 29% |
| Sep 13 | 64°F | 40°F | 87°F 1908 | 20°F 1970 | 29% |
| Sep 14 | 64°F | 40°F | 88°F 1923 | 18°F 1970 | 29% |
| Sep 15 | 63°F | 39°F | 91°F 2000 | 21°F 1912 | 30% |
| Sep 16 | 63°F | 39°F | 90°F 1938 | 25°F 1973 | 30% |
| Sep 17 | 62°F | 39°F | 90°F 1981 | 24°F 1973 | 30% |
| Sep 18 | 62°F | 39°F | 94°F 1981 | 23°F 1991 | 30% |
| Sep 19 | 61°F | 39°F | 90°F 2009 | 14°F 1957 | 31% |
| Sep 20 | 61°F | 38°F | 86°F 1922 | 17°F 1934 | 31% |
| Sep 21 | 60°F | 38°F | 88°F 1967 | 20°F 1995 | 31% |
| Sep 22 | 60°F | 38°F | 87°F 1938 | 16°F 1934 | 31% |
| Sep 23 | 59°F | 38°F | 92°F 2009 | 15°F 1926 | 32% |
| Sep 24 | 59°F | 37°F | 92°F 2001 | 0°F 1926 | 32% |
| Sep 25 | 59°F | 37°F | 90°F 2014 | -4°F 1934 | 32% |
| Sep 26 | 58°F | 37°F | 89°F 1963 | 4°F 1908 | 32% |
| Sep 27 | 58°F | 37°F | 87°F 1922 | 18°F 1908 | 33% |
| Sep 28 | 57°F | 36°F | 91°F 2022 | 20°F 1984 | 33% |
| Sep 29 | 57°F | 36°F | 91°F 1967 | 18°F 1929 | 33% |
| Sep 30 | 56°F | 36°F | 89°F 1992 | 6°F 2019 | 33% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (MDT).
- September 1
- sunrise 6:49 AM, sunset 8:14 PM
- September 30
- sunrise 7:30 AM, sunset 7:13 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USW00004130 (St. Mary 1 Ssw), public domain. Records: NOAA GHCN-Daily, station USW00024137, 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.