September weather in Grand Lake, CO
The average temperature in Grand Lake in September is 49.7°F (31.8°F–67.6°F). Average precipitation: 1.59 inches. Average snowfall is 0.4 inches.
September is a fall month in Grand Lake, and is warmer than the annual average of 36.9°F. Daily temperatures swing about 35.8°F between overnight low and afternoon high. Expect about 12 days with precipitation. Daylight averages about 12h 15m. For travel, September is cool.
Avg High
67.6°F
Avg Low
31.8°F
Precipitation
1.59 in
Snow
0.4 in
September records in Grand Lake
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 84.0°F (1960) | 19.9°F (1956) | 0.75 in (1984) |
| September 2 | 82.0°F (1947) | 21.9°F (1952) | 0.42 in (1918) |
| September 3 | 82.9°F (1948) | 21.9°F (1959) | 0.52 in (1961) |
| September 4 | 88.0°F (1959) | 23.0°F (1943) | 0.90 in (1997) |
| September 5 | 88.0°F (1978) | 23.0°F (1953) | 0.60 in (2004) |
| September 6 | 89.1°F (1978) | 19.9°F (1956) | 0.59 in (2007) |
| September 7 | 86.0°F (1978) | 16.0°F (1964) | 0.75 in (2003) |
| September 8 | 84.9°F (1988) | 23.0°F (1948) | 0.75 in (1971) |
| September 9 | 82.0°F (2021) | 17.1°F (1962) | 1.13 in (1941) |
| September 10 | 82.9°F (2022) | 14.0°F (1962) | 0.75 in (1947) |
| September 11 | 86.0°F (1988) | 21.0°F (1955) | 1.10 in (1916) |
| September 12 | 84.0°F (1958) | 21.0°F (1957) | 1.86 in (2008) |
| September 13 | 82.9°F (1990) | 16.0°F (1978) | 1.76 in (1993) |
| September 14 | 82.9°F (1990) | 19.9°F (1951) | 0.95 in (1914) |
| September 15 | 82.0°F (1990) | 19.9°F (1979) | 0.50 in (1987) |
| September 16 | 82.9°F (2000) | 15.1°F (1951) | 2.22 in (1984) |
| September 17 | 82.0°F (2000) | 18.0°F (1951) | 0.74 in (2007) |
| September 18 | 82.0°F (1981) | 17.1°F (1971) | 0.60 in (1960) |
| September 19 | 78.1°F (2010) | 14.0°F (1971) | 0.91 in (1964) |
| September 20 | 79.0°F (2010) | 17.1°F (1971) | 0.89 in (1997) |
| September 21 | 79.0°F (1944) | 12.0°F (1978) | 0.51 in (1961) |
| September 22 | 75.9°F (1954) | 15.1°F (1957) | 1.85 in (1961) |
| September 23 | 75.0°F (1992) | 12.9°F (1956) | 0.75 in (1961) |
| September 24 | 79.0°F (1963) | 15.1°F (1956) | 0.69 in (1954) |
| September 25 | 81.0°F (2024) | 7.0°F (1961) | 0.85 in (1915) |
| September 26 | 82.0°F (2024) | 12.9°F (1970) | 0.55 in (1959) |
| September 27 | 81.0°F (2001) | 12.0°F (1973) | 1.00 in (1959) |
| September 28 | 80.1°F (2001) | 17.1°F (2020) | 3.20 in (1985) |
| September 29 | 80.1°F (2024) | 14.0°F (1999) | 0.65 in (1960) |
| September 30 | 75.0°F (1957) | 7.0°F (1959) | 0.60 in (1940) |