Boulder County, CO
Tuesday : a low of 48.4°F averaged over Boulder County, CO, the warmest 29 September night in the county average since the data begin in 1951 (county average from NOAA gridded data, 1951 to 2026).
Last updated . This page normally updates every day; the latest update is late.
- High
- 65.6°F
- Coldest since 2020
- 30th coldest of 76
- Low
- 48.4°F
- Warmest since the data begin
- Warmest of 76
- Precipitation
- 0.01 in
- Wettest since 2025
- 20th wettest of 76
- Normal range, 32.3 to 44.9°F
Every year as a table
Every 29 September high of the county average in Boulder County, CO since 1951: 65.6°F in 2026; the highest is 82.2°F, in 2010.
| Year | High, °F | Low, °F |
|---|---|---|
| 2026 | 65.6 | 48.4 |
| 2025 | 70.5 | 43.1 |
| 2024 | 79.6 | 44.9 |
| 2023 | 77.9 | 43.4 |
| 2022 | 73.8 | 45 |
| 2021 | 71.5 | 47.2 |
| 2020 | 56.6 | 31.4 |
| 2019 | 67.7 | 41.7 |
| 2018 | 58 | 34.5 |
| 2017 | 52.6 | 38.7 |
| 2016 | 73.3 | 40.6 |
| 2015 | 73.4 | 47.6 |
| 2014 | 66.2 | 44.9 |
| 2013 | 59.4 | 31.8 |
| 2012 | 64.4 | 37.3 |
| 2011 | 77.9 | 44.7 |
| 2010 | 82.2 | 45.2 |
| 2009 | 65.7 | 32.4 |
| 2008 | 75.6 | 38.1 |
| 2007 | 70.6 | 41.4 |
| 2006 | 70.2 | 34.6 |
| 2005 | 52.3 | 35.2 |
| 2004 | 58.1 | 37.6 |
| 2003 | 65 | 33.8 |
| 2002 | 63 | 38 |
| 2001 | 77.7 | 46.4 |
| 2000 | 71.9 | 40.1 |
| 1999 | 39.3 | 21.9 |
| 1998 | 77.5 | 43.5 |
| 1997 | 69.4 | 38.1 |
| 1996 | 65.4 | 36.5 |
| 1995 | 63.2 | 40.5 |
| 1994 | 79.6 | 40.5 |
| 1993 | 67.9 | 36.1 |
| 1992 | 70.8 | 35.9 |
| 1991 | 74.7 | 43.2 |
| 1990 | 57.3 | 41.8 |
| 1989 | 75.3 | 43.1 |
| 1988 | 51.5 | 29.4 |
| 1987 | 62.6 | 32.2 |
| 1986 | 58.2 | 36.5 |
| 1985 | 35.9 | 17.6 |
| 1984 | 35.2 | 22.2 |
| 1983 | 68.2 | 42.5 |
| 1982 | 57.7 | 35.5 |
| 1981 | 77.8 | 44.1 |
| 1980 | 77 | 42 |
| 1979 | 72 | 39.2 |
| 1978 | 73.7 | 41.1 |
| 1977 | 75.2 | 43.4 |
| 1976 | 59.8 | 30.8 |
| 1975 | 66.5 | 34.1 |
| 1974 | 62 | 32.1 |
| 1973 | 48.4 | 34.8 |
| 1972 | 61 | 35.1 |
| 1971 | 62.6 | 32.8 |
| 1970 | 66.2 | 37.3 |
| 1969 | 76.9 | 42.2 |
| 1968 | 64.1 | 40.4 |
| 1967 | 75.4 | 39.1 |
| 1966 | 71.8 | 40.6 |
| 1965 | 53.7 | 37.2 |
| 1964 | 70.1 | 37.5 |
| 1963 | 70.1 | 37.7 |
| 1962 | 63.8 | 43.6 |
| 1961 | 64.4 | 35.7 |
| 1960 | 67 | 37.9 |
| 1959 | 40.5 | 26 |
| 1958 | 69.8 | 39.8 |
| 1957 | 78.5 | 42.3 |
| 1956 | 69.7 | 42.7 |
| 1955 | 70.3 | 35.6 |
| 1954 | 67.8 | 37.4 |
| 1953 | 72.3 | 42.8 |
| 1952 | 72.1 | 41.8 |
| 1951 | 67 | 38.7 |
The month
September 2026 so far averaged 61.9°F in Boulder County, CO, the warmest 1 to 29 September in the county average since the data begin in 1951 (county average from NOAA gridded data, 1951 to 2026).
The month in words
- August 2026 averaged 67.9°F in Boulder County, CO, the warmest August in the county average since the data begin in 1895 (county average from NOAA's monthly county data, 1895 to 2026).
- Tuesday 29 September 2026: a high of 65.6°F averaged over Boulder County, CO, the coldest 29 September day in the county average since 2020, 30th coldest of 76 (county average from NOAA gridded data, 1951 to 2026).
- Tuesday 29 September 2026: 0.01 in of precipitation averaged over Boulder County, CO, the wettest 29 September in the county average since 2025, tied 20th wettest of 76 (with 2025, 2019, 1995 and 3 other years) (county average from NOAA gridded data, 1951 to 2026).
- Days of the month without a value
- 0
Nearby
Denver, CO 42.8 mi, the nearest city with its own station