MUD MOUNTAIN DAM, WASHINGTON

NCDC 1971-2000 Monthly Normals

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
Monthly
Mean Max. Temperature (F) 43.8 46.8 50.4 54.8 60.2 65.2 71.6 72.9 68.0 58.5 48.3 43.6 57.0
Highest Mean Max. Temperature (F) 50.8 53.3 55.0 58.4 66.9 70.9 79.4 78.1 75.5 65.3 55.1 48.6 79.4
Year Highest Occurred 1981 1991 1992 1989 1992 1992 1985 1981 1974 1987 1997 1997 1985
Lowest Mean Max. Temperature (F) 36.1 37.8 45.4 50.1 55.8 59.0 64.1 66.1 61.8 54.2 36.8 36.3 36.1
Year Lowest Occurred 2000 1989 1971 1975 1974 1971 1993 1976 2000 2000 1985 1990 2000
Mean Temperature (F) 37.6 39.6 42.3 46.0 51.1 55.9 61.0 61.7 57.2 49.2 41.5 37.5 48.4
Highest Mean Temperature (F) 44.7 45.3 46.8 49.2 55.9 59.9 65.7 65.6 61.9 53.1 47.4 42.2 65.7
Year Highest Occurred 1981 1992 1992 1992 1997 1982 1985 1981 1974 1987 1997 1979 1985
Lowest Mean Temperature (F) 31.4 31.4 37.4 40.1 47.2 51.2 56.5 57.6 53.2 45.2 31.1 30.6 30.6
Year Lowest Occurred 1980 1989 1971 1975 1999 1971 2000 1973 2000 1984 1985 1990 1990
Mean Min. Temperature (F) 31.4 32.3 34.2 37.1 42.0 46.5 50.3 50.5 46.3 39.9 34.7 31.3 39.7
Highest Mean Min. Temperature (F) 38.6 38.8 38.6 40.7 47.0 49.6 55.0 53.3 49.5 43.9 39.9 35.8 55.0
Year Highest Occurred 1981 1992 1992 1990 1993 1982 1998 1997 1997 1988 1995 1979 1998
Lowest Mean Min. Temperature (F) 24.6 25.0 29.3 30.1 37.1 43.2 47.6 45.3 42.6 34.9 25.3 24.8 24.6
Year Lowest Occurred 1980 1989 1971 1975 1999 1976 1999 1973 1972 1984 1985 1990 1980
Mean Precipitation (in.) 6.65 5.36 5.44 5.11 4.48 3.90 2.17 2.13 2.97 4.60 8.18 6.76 57.75
Highest Precipitation (in.) 12.87 10.42 9.58 8.66 7.89 6.89 7.09 8.28 8.39 9.26 14.54 12.51 14.54
Year Highest Occurred 1990 1996 1988 1993 1984 1993 1983 1975 1978 1975 1990 1975 1990
Lowest Precipitation (in.) 1.12 0.36 2.52 2.42 1.32 1.26 0.03 0.29 0.12 0.41 2.41 1.07 0.03
Year Lowest Occurred 1985 1993 1992 1998 1982 1979 1984 1998 1993 1987 1979 1985 1984
Heating Degree Days (F) 850. 712. 704. 571. 431. 278. 154. 137. 248. 491. 705. 854. 6135.
Cooling Degree Days (F) 0. 0. 0. 0. 0. 3. 29. 34. 12. 0. 0. 0. 78.

Western Regional Climate Center, wrcc@dri.edu