September weather in Granby, CO
The average temperature in Granby in September is 51.3°F (35.8°F–66.9°F). Average precipitation: 1.46 inches.
September is a fall month in Granby, and is warmer than the annual average of 37.4°F. Daily temperatures swing about 31.1°F between overnight low and afternoon high. Expect about 10 days with precipitation. Daylight averages about 12h 15m. For travel, September is cool.
Avg High
66.9°F
Avg Low
35.8°F
Precipitation
1.46 in
Daylight
12h 15m
September records in Granby
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 82.9°F (1988) | 25.0°F (1956) | 0.58 in (1984) |
| September 2 | 81.0°F (2002) | 28.0°F (1959) | 0.26 in (2021) |
| September 3 | 81.0°F (1998) | 26.1°F (2006) | 0.57 in (1961) |
| September 4 | 82.9°F (1998) | 27.0°F (2008) | 0.31 in (1983) |
| September 5 | 82.9°F (1998) | 28.0°F (1950) | 0.38 in (1982) |
| September 6 | 82.0°F (1978) | 27.0°F (1956) | 0.93 in (2003) |
| September 7 | 81.0°F (1978) | 23.0°F (2010) | 0.41 in (2011) |
| September 8 | 80.1°F (2022) | 24.1°F (1948) | 0.62 in (2001) |
| September 9 | 78.1°F (1979) | 24.1°F (1962) | 0.70 in (2006) |
| September 10 | 78.1°F (2021) | 21.0°F (1962) | 0.32 in (2013) |
| September 11 | 79.0°F (2021) | 24.1°F (1948) | 0.56 in (2020) |
| September 12 | 79.0°F (1990) | 25.0°F (1948) | 1.53 in (2008) |
| September 13 | 81.0°F (1990) | 21.9°F (1951) | 1.10 in (1993) |
| September 14 | 81.0°F (1990) | 21.9°F (2003) | 0.66 in (1957) |
| September 15 | 82.0°F (1990) | 24.1°F (1979) | 0.47 in (2009) |
| September 16 | 80.1°F (2000) | 19.0°F (1951) | 0.58 in (1959) |
| September 17 | 81.0°F (2000) | 21.0°F (1951) | 0.69 in (2007) |
| September 18 | 77.0°F (2004) | 16.0°F (1971) | 0.32 in (2001) |
| September 19 | 78.1°F (2014) | 19.9°F (1971) | 0.74 in (1964) |
| September 20 | 78.1°F (2010) | 21.0°F (1975) | 0.88 in (1997) |
| September 21 | 78.1°F (1966) | 15.1°F (1983) | 0.41 in (2004) |
| September 22 | 75.0°F (2001) | 18.0°F (1995) | 1.17 in (1961) |
| September 23 | 75.0°F (1949) | 19.0°F (1956) | 0.85 in (1961) |
| September 24 | 75.0°F (2015) | 21.0°F (1956) | 0.84 in (1959) |
| September 25 | 75.0°F (1948) | 17.1°F (1961) | 0.38 in (1990) |
| September 26 | 77.0°F (2024) | 18.0°F (1970) | 0.46 in (2002) |
| September 27 | 78.1°F (2001) | 19.9°F (1973) | 0.59 in (1959) |
| September 28 | 78.1°F (2001) | 19.9°F (1959) | 0.68 in (2005) |
| September 29 | 75.9°F (2010) | 18.0°F (1988) | 0.90 in (2014) |
| September 30 | 75.9°F (2024) | 14.0°F (1959) | 1.28 in (1993) |