September weather in Chester, MT
The average temperature in Chester in September is 55.7°F (40.5°F–71.0°F). Average precipitation: 1.00 inches. Average snowfall is 0.6 inches.
September is a fall month in Chester, and is warmer than the annual average of 41.4°F. Daily temperatures swing about 30.5°F between overnight low and afternoon high. Expect about 6 days with precipitation. Daylight averages about 12h 20m. For travel, September is a comfortable month to visit.
Avg High
71.0°F
Avg Low
40.5°F
Precipitation
1.00 in
Snow
0.6 in
September records in Chester
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 96.1°F (1991) | 25.0°F (1914) | 1.27 in (2008) |
| September 2 | 96.1°F (1955) | 23.0°F (1962) | 0.95 in (1915) |
| September 3 | 97.0°F (1950) | 23.0°F (1962) | 0.82 in (1916) |
| September 4 | 93.9°F (1950) | 28.0°F (1962) | 2.35 in (1911) |
| September 5 | 96.1°F (1967) | 21.0°F (1956) | 1.15 in (2015) |
| September 6 | 93.9°F (1967) | 27.0°F (1956) | 0.84 in (1985) |
| September 7 | 99.0°F (2022) | 25.0°F (1992) | 0.78 in (1946) |
| September 8 | 93.0°F (1981) | 21.9°F (1943) | 0.28 in (1946) |
| September 9 | 93.0°F (1981) | 21.0°F (1962) | 0.42 in (1915) |
| September 10 | 90.0°F (1968) | 25.0°F (1983) | 0.67 in (2005) |
| September 11 | 91.0°F (1958) | 19.9°F (1989) | 0.45 in (1988) |
| September 12 | 90.0°F (1958) | 19.9°F (1989) | 0.63 in (1978) |
| September 13 | 91.0°F (1953) | 21.0°F (1970) | 0.68 in (2024) |
| September 14 | 89.1°F (1946) | 3.9°F (1914) | 0.51 in (1991) |
| September 15 | 96.1°F (2000) | 19.0°F (1970) | 0.50 in (2006) |
| September 16 | 89.1°F (1979) | 21.9°F (1955) | 0.41 in (1954) |
| September 17 | 88.0°F (1981) | 21.9°F (1965) | 0.76 in (1996) |
| September 18 | 93.0°F (2009) | 21.0°F (1904) | 0.93 in (1947) |
| September 19 | 90.0°F (1981) | 15.1°F (1904) | 1.21 in (2024) |
| September 20 | 91.0°F (2009) | 21.0°F (1914) | 1.30 in (1968) |
| September 21 | 89.1°F (1967) | 15.1°F (1995) | 0.24 in (1968) |
| September 22 | 88.0°F (1987) | 18.0°F (1904) | 0.67 in (1945) |
| September 23 | 89.1°F (1990) | 12.9°F (1946) | 0.71 in (2023) |
| September 24 | 91.9°F (2001) | 18.0°F (1961) | 0.50 in (1951) |
| September 25 | 93.9°F (2001) | 15.1°F (1904) | 1.00 in (1908) |
| September 26 | 93.0°F (2011) | 19.9°F (1955) | 0.63 in (1999) |
| September 27 | 88.0°F (1957) | 15.1°F (1961) | 1.03 in (1982) |
| September 28 | 89.1°F (1967) | 15.1°F (1972) | 0.58 in (2019) |
| September 29 | 90.0°F (1963) | 8.1°F (2019) | 0.34 in (2022) |
| September 30 | 90.0°F (1992) | 10.9°F (2019) | 0.48 in (1977) |