LAKE YELLOWSTONE, WYOMING

NCDC 1961-1990 Monthly Normals

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
Mean Max. Temperature (F) 21.3 27.2 33.6 41.5 51.1 61.1 71.1 70.1 59.7 48.2 33.3 23.9 45.2
Highest Mean Max. Temperature (F) 32.6 34.0 42.3 50.2 58.7 70.7 77.2 76.1 68.0 57.7 38.1 32.6 48.7
Year Highest Occurred 1981 1963 1986 1987 1986 1988 1988 1969 1990 1988 1981 1980 1987
Lowest Mean Max. Temperature (F) 11.2 21.3 25.5 33.8 45.9 54.7 64.5 63.4 49.6 41.1 28.9 16.0 42.8
Year Lowest Occurred 1979 1964 1965 1970 1975 1964 1986 1968 1961 1969 1973 1990 1975
Mean Temperature (F) 8.6 12.6 17.9 27.7 37.7 46.9 54.6 53.3 44.2 34.3 22.0 12.1 31.0
Highest Mean Temperature (F) 18.3 20.4 27.0 35.9 46.0 54.0 58.0 58.9 50.7 40.6 27.1 22.1 34.6
Year Highest Occurred 1981 1986 1986 1987 1987 1988 1988 1969 1990 1988 1981 1980 1987
Lowest Mean Temperature (F) -3.0 2.6 4.7 19.5 32.6 41.9 50.7 48.4 37.9 28.2 15.8 3.3 28.0
Year Lowest Occurred 1979 1985 1965 1975 1975 1975 1972 1975 1965 1984 1985 1990 1985
Mean Min. Temperature (F) -4.2 -2.1 2.2 13.9 24.2 32.6 38.0 36.5 28.6 20.4 10.7 0.4 16.8
Highest Mean Min. Temperature (F) 4.3 9.9 11.6 21.5 33.3 37.2 42.8 42.0 34.9 25.7 16.2 11.5 20.5
Year Highest Occurred 1967 1986 1986 1987 1987 1988 1987 1983 1966 1983 1965 1980 1987
Lowest Mean Min. Temperature (F) -17.1 -16.4 -16.1 4.2 11.1 27.5 32.7 30.2 22.3 14.5 2.2 -9.5 12.0
Year Lowest Occurred 1979 1985 1965 1975 1986 1975 1972 1985 1985 1984 1985 1990 1985
Mean Precipitation (in.) 2.00 1.48 1.59 1.36 1.79 2.14 1.58 1.83 1.83 1.34 1.73 1.76 20.43
Highest Precipitation (in.) 5.62 5.31 4.06 2.78 4.70 6.36 4.13 5.00 4.09 5.38 3.88 4.64 28.37
Year Highest Occurred 1969 1986 1974 1982 1981 1969 1985 1968 1961 1975 1986 1964 1986
Lowest Precipitation (in.) 0.28 0.35 0.48 0.42 0.52 0.49 0.34 0.34 0.11 0.06 0.37 0.06 12.62
Year Lowest Occurred 1961 1977 1969 1987 1969 1961 1976 1988 1987 1986 1976 1986 1976
Heating Degree Days (F) 1748. 1467. 1460. 1119. 846. 543. 322. 366. 624. 952. 1290. 1640. 12377.
Cooling Degree Days (F) 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.

Western Regional Climate Center, wrcc@dri.edu