Year Annual DJF MAM JJA SON 1957 -27.6 -999.0 -34.0 -34.4 -25.9 1958 -29.1 -14.0 -28.8 -41.0 -30.7 1959 -27.5 -17.9 -27.2 -35.1 -30.7 1960 -28.3 -18.0 -31.4 -34.9 -28.6 1961 -27.9 -15.6 -29.8 -35.4 -30.5 1962 -29.7 -18.1 -31.4 -36.8 -32.5 1963 -27.6 -16.7 -31.4 -34.5 -27.4 1964 -27.3 -18.4 -28.4 -34.9 -28.3 1965 -26.7 -15.6 -31.0 -32.3 -28.4 1966 -26.5 -14.8 -28.5 -34.3 -28.2 1967 -27.0 -13.6 -29.0 -34.0 -31.3 1968 -28.7 -14.4 -29.9 -38.9 -31.0 1969 -27.9 -17.3 -29.2 -36.3 -28.9 1970 -26.0 -16.0 -27.6 -32.6 -28.0 1971 -27.7 -15.3 -28.6 -37.4 -29.0 1972 -25.7 -16.4 -27.7 -32.3 -26.6 1973 -26.4 -16.3 -29.7 -33.7 -26.2 1974 -26.9 -15.2 -28.6 -35.3 -28.8 1975 -27.4 -15.9 -29.4 -35.4 -28.5 1976 -28.6 -15.8 -30.4 -37.0 -31.9 1977 -28.2 -16.2 -31.2 -35.1 -29.8 1978 -28.6 -17.6 -28.9 -38.7 -29.0 1979 -27.7 -16.7 -30.9 -36.9 -27.2 1980 -24.2 -13.7 -24.2 -29.9 -28.2 1981 -28.0 -17.7 -29.1 -36.3 -29.1 1982 -28.2 -16.1 -34.8 -33.0 -29.3 1983 -29.4 -18.2 -28.6 -40.7 -29.4 1984 -26.4 -16.8 -26.3 -36.1 -27.4 1985 -27.3 -16.5 -28.4 -36.9 -26.3 1986 -28.4 -16.8 -27.5 -38.0 -31.8 1987 -26.6 -15.7 -32.4 -29.7 -28.7 1988 -25.0 -16.1 -29.1 -30.3 -24.8 1989 -26.5 -14.9 -28.4 -34.8 -27.5 1990 -28.1 -15.4 -29.9 -38.5 -28.6 1991 -26.0 -14.8 -29.2 -35.1 -25.8 1992 -25.0 -16.0 -25.2 -32.0 -26.1 1993 -25.2 -14.5 -29.6 -28.6 -27.8 1994 -26.4 -17.0 -28.5 -34.5 -26.3 1995 -26.7 -14.2 -31.4 -32.1 -28.3 1996 -26.6 -16.2 -29.0 -33.7 -28.0 1997 -26.2 -15.2 -31.3 -34.0 -25.1 1998 -26.5 -13.2 -28.0 -33.5 -30.1 1999 -26.4 -16.4 -30.9 -34.4 -23.9 2000 -25.2 -16.8 -28.3 -31.1 -24.1 2001 -26.0 -15.9 -25.5 -34.3 -28.4 2002 -24.5 -16.2 -25.8 -33.6 -22.5 2003 -26.2 -15.5 -27.4 -35.1 -27.0 2004 -28.5 -15.9 -30.7 -38.0 -29.0 2005 -25.2 -15.6 -30.1 -32.5 -23.0 2006 -26.7 -13.2 -34.0 -32.6 -26.3 2007 -24.8 -14.8 -25.1 -32.0 -27.4 2008 -26.2 -15.4 -28.1 -35.4 -25.1 2009 -25.9 -17.1 -28.5 -31.5 -27.8 2010 -27.3 -14.9 -29.2 -35.9 -28.0 2011 -25.9 -17.3 -29.3 -28.8 -28.2 2012 -26.7 -16.4 -26.9 -36.9 -27.6 2013 -27.9 -14.6 -30.4 -37.3 -28.7 2014 -26.3 -16.3 -28.7 -33.6 -25.2 2015 -28.1 -16.1 -30.8 -39.0 -27.1 2016 -26.9 -16.8 -30.6 -33.4 -27.7 2017 -27.0 -15.1 -25.5 -35.2 -31.2 2018 -27.6 -17.4 -30.4 -36.3 -26.7 2019 -25.8 -15.6 -30.3 -30.9 -27.0 2020 -26.8 -14.7 -28.6 -33.9 -29.1 2021 -28.0 -18.0 -32.1 -33.3 -28.3