BOULDER, COLORADO

NCDC 1961-1990 Monthly Normals

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
Mean Max. Temperature (F) 45.2 48.3 53.9 62.8 71.6 81.5 87.5 85.1 76.7 66.9 53.0 45.6 64.8
Highest Mean Max. Temperature (F) 57.1 55.3 62.2 71.2 77.9 89.5 91.3 91.0 83.9 72.7 59.0 57.2 66.8
Year Highest Occurred 1986 1970 1986 1981 1966 1980 1964 1983 1983 1963 1962 1980 1981
Lowest Mean Max. Temperature (F) 35.7 35.3 43.4 55.1 66.5 73.7 81.6 81.1 68.8 52.9 41.5 32.6 62.8
Year Lowest Occurred 1979 1989 1965 1973 1971 1969 1990 1979 1965 1969 1985 1983 1973
Mean Temperature (F) 32.6 35.9 41.0 49.2 58.0 67.1 73.0 71.0 62.4 52.9 40.8 33.6 51.5
Highest Mean Temperature (F) 42.3 41.1 48.8 56.7 63.5 71.7 77.7 75.4 68.3 60.1 46.0 44.1 53.6
Year Highest Occurred 1986 1976 1986 1981 1966 1980 1966 1983 1963 1963 1981 1980 1963
Lowest Mean Temperature (F) 22.6 24.1 30.8 42.7 54.1 62.2 68.6 67.9 55.9 41.8 31.1 22.4 49.8
Year Lowest Occurred 1979 1989 1965 1973 1983 1969 1990 1979 1965 1969 1985 1983 1973
Mean Min. Temperature (F) 19.9 23.3 28.1 35.6 44.4 52.8 58.5 56.8 48.0 38.8 28.5 21.6 38.0
Highest Mean Min. Temperature (F) 27.4 29.0 35.3 42.1 49.0 56.2 64.1 60.4 55.1 47.4 34.6 31.0 40.4
Year Highest Occurred 1986 1976 1986 1981 1966 1963 1966 1970 1963 1963 1981 1980 1963
Lowest Mean Min. Temperature (F) 9.5 12.8 18.2 30.3 40.0 48.3 54.5 53.6 43.0 30.7 20.7 12.1 36.3
Year Lowest Occurred 1979 1989 1965 1973 1990 1982 1972 1978 1965 1969 1985 1983 1978
Mean Precipitation (in.) 0.59 0.72 1.63 2.16 3.00 2.22 1.97 1.31 1.86 1.27 1.07 0.78 18.58
Highest Precipitation (in.) 1.52 2.44 4.60 6.01 8.66 6.04 5.20 3.94 4.89 5.39 3.46 2.16 27.52
Year Highest Occurred 1962 1987 1983 1971 1969 1987 1965 1967 1961 1969 1983 1988 1969
Lowest Precipitation (in.) 0.02 0.03 0.31 0.15 0.00 0.32 0.00 0.03 0.15 0.03 0.01 0.13 11.13
Year Lowest Occurred 1982 1970 1966 1963 1974 1980 1979 1985 1977 1988 1984 1977 1966
Heating Degree Days (F) 1004. 815. 744. 474. 235. 53. 0. 7. 136. 387. 726. 973. 5554.
Cooling Degree Days (F) 0. 0. 0. 0. 18. 116. 252. 193. 58. 12. 0. 0. 649.

Western Regional Climate Center, wrcc@dri.edu