September weather in Hamilton, MT
The average temperature in Hamilton in September is 56.2°F (40.4°F–71.9°F). Average precipitation: 0.81 inches.
September is a fall month in Hamilton, and is warmer than the annual average of 44.8°F. Daily temperatures swing about 31.5°F between overnight low and afternoon high. Expect about 6 days with precipitation. Daylight averages about 12h 19m. For travel, September is a comfortable month to visit.
Avg High
71.9°F
Avg Low
40.4°F
Precipitation
0.81 in
Daylight
12h 19m
September records in Hamilton
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 98.1°F (1967) | 28.0°F (1895) | 0.78 in (1961) |
| September 2 | 98.1°F (1998) | 28.9°F (1895) | 0.65 in (1989) |
| September 3 | 93.9°F (1931) | 28.0°F (1895) | 0.50 in (1936) |
| September 4 | 93.9°F (1998) | 24.1°F (1895) | 0.62 in (1936) |
| September 5 | 95.0°F (1955) | 19.0°F (1895) | 0.46 in (2001) |
| September 6 | 93.9°F (2020) | 17.1°F (1895) | 1.70 in (1911) |
| September 7 | 98.1°F (1931) | 10.0°F (1895) | 0.60 in (2016) |
| September 8 | 93.9°F (2022) | 21.0°F (1895) | 1.06 in (1973) |
| September 9 | 91.9°F (2021) | 28.0°F (1895) | 0.70 in (1931) |
| September 10 | 95.0°F (1935) | 28.0°F (1895) | 0.31 in (1998) |
| September 11 | 95.0°F (1935) | 27.0°F (1895) | 0.77 in (1980) |
| September 12 | 91.9°F (1953) | 19.9°F (1895) | 0.56 in (1985) |
| September 13 | 93.0°F (2015) | 19.9°F (1895) | 0.78 in (1950) |
| September 14 | 90.0°F (1948) | 19.0°F (1895) | 0.44 in (1973) |
| September 15 | 91.9°F (2002) | 21.9°F (1895) | 1.45 in (1954) |
| September 16 | 87.1°F (1989) | 21.0°F (1895) | 1.02 in (1947) |
| September 17 | 91.9°F (2009) | 19.0°F (1895) | 0.56 in (1947) |
| September 18 | 90.0°F (1984) | 24.1°F (1965) | 0.99 in (1957) |
| September 19 | 90.0°F (1901) | 27.0°F (1965) | 0.57 in (1970) |
| September 20 | 87.1°F (1899) | 19.0°F (1895) | 0.86 in (1968) |
| September 21 | 93.9°F (1936) | 16.0°F (1895) | 0.70 in (1937) |
| September 22 | 89.1°F (1938) | 16.0°F (1895) | 0.82 in (1934) |
| September 23 | 87.1°F (1903) | 17.1°F (1895) | 0.95 in (2007) |
| September 24 | 91.0°F (2011) | 18.0°F (1934) | 0.40 in (1992) |
| September 25 | 93.9°F (2014) | 25.0°F (1933) | 0.54 in (2013) |
| September 26 | 90.0°F (2015) | 21.0°F (1972) | 0.42 in (1948) |
| September 27 | 90.0°F (1899) | 25.0°F (1961) | 0.90 in (1982) |
| September 28 | 87.1°F (1967) | 25.0°F (1999) | 1.43 in (1940) |
| September 29 | 89.1°F (2010) | 21.0°F (1985) | 0.29 in (1909) |
| September 30 | 86.0°F (1963) | 18.0°F (1985) | 0.50 in (1947) |