MONTHLY NAO INDEX BASED ON RAW ANOMALIES JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 1874 13.5 4.3 2.5 8.7 -5.6 -0.8 2.0 1.8 5.2 8.7 -3.0 -5.5 1875 -6.0 -11.7 -9.3 -7.8 10.1 8.4 -3.9 -4.5 -4.4 -2.2 -19.4 -0.8 1876 5.9 -7.9 -0.4 -5.0 1.0 9.6 6.2 0.2 -14.1 -10.4 -24.9 -12.6 1877 8.2 5.9 -2.4 -15.4 -10.8 -1.5 2.8 -15.9 -11.3 -0.8 10.7 11.7 1878 1.9 -2.5 -3.6 -12.3 -2.4 -4.5 1.9 -9.5 3.8 -7.9 -19.9 -33.3 1879 -9.9 2.7 2.7 -2.1 4.5 -4.1 -3.4 -2.7 10.7 -4.9 -22.5 -6.0 1880 -10.5 8.0 -6.4 5.8 -2.6 -2.5 -9.2 -2.3 -4.5 -31.9 2.7 -14.3 1881 -42.7 -13.7 -18.2 -9.5 0.7 2.3 3.8 -3.6 -9.0 -9.7 8.1 14.3 1882 8.0 1.2 19.3 -9.4 -6.3 -3.8 3.7 -0.1 3.6 -2.3 6.1 -11.5 1883 6.0 16.6 -19.8 4.1 3.1 -7.8 -8.3 2.4 -4.7 9.1 8.9 3.2 1884 5.0 4.1 3.5 -9.5 -0.3 1.3 -9.6 1.8 4.8 3.0 -10.1 10.8 1885 -2.7 -14.7 1.3 3.0 -8.0 3.5 -0.6 -15.4 4.8 -4.5 -6.7 -8.1 1886 0.8 -5.2 -9.5 -5.9 -6.4 1.9 1.0 8.3 -3.8 0.4 7.3 -2.5 1887 14.5 5.0 -15.6 -14.5 1.7 -6.9 -1.1 -7.6 -3.6 -16.1 -9.7 -14.8 1888 -12.5 -15.4 -12.8 -5.7 -5.3 -6.9 -6.6 -3.4 -9.3 -16.1 10.1 9.5 1889 7.8 -3.5 -5.4 7.0 1.5 5.5 -8.9 5.0 -6.0 0.9 7.7 15.6 1890 20.4 -8.1 10.0 5.7 -3.1 3.5 2.8 1.1 3.8 -2.8 12.1 -7.8 1891 -0.3 2.1 -9.8 -8.9 -4.2 -13.6 -4.8 -0.6 4.9 5.0 -1.6 10.1 1892 3.1 -17.8 -12.8 -4.8 -9.4 -6.6 -1.1 -3.7 7.8 -17.1 0.9 -9.4 1893 -16.4 2.5 -4.5 -0.7 -4.8 -8.5 -2.1 -8.6 0.7 -2.2 -14.3 13.8 1894 5.7 23.8 9.2 6.2 -5.6 7.0 0.1 -1.6 -16.2 -16.7 11.2 3.5 1895 -13.3 -38.0 1.7 -4.3 0.3 -3.9 -1.4 -4.4 -0.2 -13.9 -2.0 -2.8 1896 -6.9 5.3 13.9 9.5 1.8 -4.1 4.2 -3.2 1.1 -15.1 -6.0 11.1 1897 -10.9 7.6 2.1 15.5 0.9 -10.2 -2.2 2.0 1.2 -12.4 -5.9 4.3 1898 12.0 9.6 -5.6 10.1 -3.6 -4.3 -4.2 3.5 -2.1 -6.3 6.3 5.6 1899 -6.6 -12.0 -17.0 -2.4 -6.6 2.1 4.0 -8.7 3.5 -9.1 3.3 -4.2 1900 13.9 -25.2 -17.6 3.3 0.5 -4.0 -3.8 -2.0 7.1 -5.3 7.6 9.1 1901 2.7 -23.9 -7.1 5.3 -5.5 4.6 2.4 1.1 2.8 4.6 -14.9 1.1 1902 -1.6 -21.7 0.6 -9.8 0.5 -14.6 -8.3 -5.8 -8.8 -0.5 -1.7 4.0 1903 4.1 14.6 20.8 -1.5 3.7 -12.2 -3.4 0.4 -4.0 -8.1 2.6 2.8 1904 16.5 4.9 1.1 17.9 1.9 -3.0 -3.4 -7.1 1.4 0.7 -3.5 -5.6 1905 6.1 8.5 8.2 -8.3 3.9 -4.1 0.6 -1.0 2.2 -14.3 1.1 1.8 1906 16.4 10.9 -5.3 10.6 -11.9 -6.6 5.8 -8.4 -0.1 5.1 -1.6 6.9 1907 5.5 11.1 17.3 5.8 -11.1 0.2 -10.2 -2.9 -1.5 -3.0 7.7 3.4 1908 8.5 13.2 10.6 -8.2 3.1 1.7 -3.8 -2.6 -0.5 -5.3 -1.2 9.3 1909 12.5 -2.7 -16.2 -0.2 -9.4 -5.1 6.2 6.2 -7.8 6.7 -9.6 -10.5 1910 16.2 24.5 7.8 -4.4 7.8 -0.9 -4.4 -6.9 -5.7 -7.3 -14.2 -0.7 1911 6.8 5.0 -2.2 -4.6 11.1 -3.1 -6.0 -3.8 0.0 -8.3 1.3 8.0 1912 -7.7 -16.8 7.5 2.8 1.7 -2.2 -3.6 -6.3 -11.5 3.2 4.0 13.1 1913 5.1 -0.1 16.8 12.2 3.6 2.9 -3.9 2.0 -6.7 -9.2 20.0 3.6 1914 -0.2 12.4 5.5 7.3 10.0 6.6 -2.9 0.6 -0.7 -3.8 0.5 8.6 1915 5.8 5.1 -21.1 14.4 -9.1 -9.1 -0.6 -7.8 -10.7 1.6 -16.0 -14.6 1916 17.8 14.9 -20.9 5.0 -2.4 -6.0 -0.1 -5.3 -4.4 8.3 -2.1 -15.7 1917 -15.4 -8.9 -4.5 -10.4 -9.1 1.1 -5.5 -2.2 6.8 6.0 9.0 -10.0 1918 -26.6 18.3 3.1 -1.8 0.5 4.3 -9.9 0.7 0.3 5.0 2.1 3.6 1919 8.3 -20.9 -5.4 0.3 -3.1 11.1 -2.1 0.3 -0.5 -12.2 -11.1 13.2 1920 20.7 9.3 23.2 -5.0 9.1 -0.7 8.1 -2.6 4.4 -2.7 11.0 -9.3 1921 13.0 2.2 19.7 -0.8 10.1 -1.2 -2.2 1.4 -0.9 -4.3 -6.1 16.4 1922 6.7 20.3 0.3 -1.1 5.2 9.6 3.4 3.6 2.8 -19.0 -2.8 13.4 1923 12.7 6.8 -3.4 0.2 -1.6 1.2 6.5 -0.7 5.3 7.4 -0.7 6.8 1924 6.3 -5.0 -23.4 -9.7 -1.6 -2.0 4.5 4.0 4.1 3.1 1.1 19.9 1925 12.0 14.1 -9.1 9.0 5.6 2.1 5.6 2.1 -1.0 -8.6 -10.0 -19.7 1926 5.0 4.3 -1.7 3.8 -6.1 -6.3 1.7 1.2 -3.1 -16.5 10.9 -4.8 1927 14.9 0.9 9.6 4.5 -8.5 -2.6 -0.9 -1.2 -1.9 -16.3 0.9 -21.0 1928 24.6 12.5 -9.7 4.7 -10.9 -9.3 2.6 -5.8 -3.5 5.7 7.7 3.6 1929 -29.6 -3.5 -9.9 -13.6 5.5 -2.7 -2.0 -0.8 4.8 6.9 11.3 19.1 1930 14.3 -3.9 -8.2 -0.4 7.9 9.1 -1.6 -1.6 -12.3 1.9 5.0 13.3 1931 0.1 13.0 -25.0 6.0 -4.3 -7.6 3.7 -6.1 -7.9 -4.3 14.8 0.0 1932 11.5 -29.5 -10.2 3.2 -7.1 -4.9 2.4 3.5 1.0 5.2 3.1 4.3 1933 17.1 -17.6 2.5 -8.8 -0.9 6.3 4.6 5.0 -2.7 -10.8 -1.5 -5.2 1934 15.1 2.2 12.0 -8.9 10.4 -7.5 1.1 5.1 8.0 4.3 -3.1 -2.9 1935 -0.1 16.7 -4.0 -9.9 -7.7 1.2 9.3 4.8 -1.4 14.3 8.9 -9.0 1936 -18.1 -19.9 -8.1 -5.8 1.8 1.3 0.5 5.2 -8.7 8.5 10.2 10.4 1937 10.2 1.6 -17.2 5.1 5.1 -0.6 0.4 2.5 5.4 -3.8 -14.8 -6.9 1938 18.5 -7.1 14.6 -7.1 1.5 4.6 4.5 1.9 5.0 18.1 14.3 6.2 1939 -12.9 17.6 1.0 -2.2 0.9 -1.8 -3.1 2.8 -14.3 -7.0 5.2 -9.3 1940 -17.5 -17.1 -10.7 -2.8 0.8 5.6 -1.0 1.6 0.7 -3.2 7.0 -1.0 1941 -21.5 -7.7 -9.8 -9.3 0.3 0.6 3.8 -1.5 -5.0 -8.6 -0.7 4.9 1942 10.9 -22.4 -14.6 -2.9 -1.0 -6.2 3.3 4.3 7.5 3.4 -8.6 4.2 1943 -4.0 18.1 3.0 16.4 1.6 1.0 0.4 -7.0 8.1 2.6 5.0 6.1 1944 10.5 -4.2 -12.6 -3.4 1.6 -2.0 -8.7 4.6 2.8 6.7 1.5 6.9 1945 -16.0 19.0 2.3 -8.2 0.0 1.0 0.0 2.0 1.0 -9.8 -14.9 -10.3 1946 12.2 -2.3 -2.1 13.7 -8.5 8.1 5.4 3.5 4.9 -12.9 -6.2 8.4 1947 1.4 -34.4 -19.1 15.2 -1.9 -0.7 1.9 -2.6 6.9 -3.8 -10.9 -11.6 1948 7.1 -3.9 11.0 7.2 -2.1 -3.7 -3.2 -1.5 0.1 4.9 -8.2 -0.7 1949 10.2 15.9 -4.0 12.1 -1.4 -7.2 -3.8 -3.6 -3.5 -1.0 7.6 3.9 1950 0.1 10.6 -1.8 9.5 -8.7 -0.7 -1.6 3.4 10.3 3.0 -3.0 -6.6 1951 7.8 9.2 -15.9 -8.2 -7.9 -10.2 -0.7 4.3 -0.3 4.5 -2.6 16.6 1952 14.8 -8.8 -15.9 10.8 -7.9 -1.2 0.3 -2.7 -7.3 -2.5 -11.6 -5.4 1953 -5.2 3.2 0.1 -10.2 -4.9 2.8 3.3 4.3 3.7 6.5 12.4 7.6 1954 1.8 9.2 2.1 1.8 -6.9 2.8 7.3 -1.7 6.7 4.5 11.4 11.6 1955 -11.2 -17.8 -18.9 2.8 0.1 -1.2 3.3 3.3 11.7 -8.5 -16.6 -3.4 1956 -3.2 -17.8 1.1 -6.2 18.1 0.8 -2.7 -4.7 -3.3 3.5 9.4 10.6 1957 16.8 -6.8 -10.9 2.8 -1.9 -10.2 -6.7 1.3 -7.3 12.5 -10.6 8.6 1958 -0.2 -16.8 -19.9 6.8 -3.9 -7.2 -6.7 -1.7 -4.3 6.5 6.4 -5.4 1959 -21.2 10.2 9.1 2.8 -2.9 3.8 3.3 -0.7 -1.3 5.5 4.4 12.6 1960 -14.2 -23.8 -7.9 6.8 -0.9 0.8 3.3 -11.7 2.7 -16.5 0.4 12.6 1961 5.8 7.2 1.1 -4.2 -1.9 11.8 0.5 5.3 8.7 7.5 0.4 -23.5 1962 16.8 3.2 -29.9 0.8 -0.9 -0.2 -6.7 2.3 -1.3 -0.5 -4.6 -7.4 1963 -37.2 -11.8 3.1 -3.2 19.1 -5.2 -3.7 0.3 8.7 10.5 -5.6 -15.4 1964 -9.2 -11.8 -9.9 5.8 7.1 -0.2 6.3 -7.7 -3.3 4.5 1.4 0.6 1965 -1.2 -30.8 -10.9 13.8 -3.9 3.8 -2.7 3.3 -0.3 -2.5 -14.6 2.6 1966 -24.2 -19.8 0.1 -4.2 8.1 2.8 2.3 -8.7 -3.3 -15.5 2.4 11.6 1967 -12.2 11.2 13.1 3.8 -2.9 6.8 0.3 0.3 1.7 9.5 4.4 -6.4 1968 2.8 -12.8 8.1 -8.2 -4.9 1.8 -9.7 -2.7 -3.3 -16.5 -9.6 -9.4 1969 -21.2 -24.8 -18.9 5.8 -4.9 1.8 5.3 -1.7 6.7 3.5 -1.6 5.6 1970 -15.2 4.2 -9.9 4.8 8.1 2.8 1.3 -0.7 1.7 -3.5 -0.6 -10.4 1971 -5.8 7.9 -1.6 -6.7 10.5 -6.6 -3.9 7.1 -4.7 -1.4 4.5 5.1 1972 5.1 3.0 6.4 6.5 8.6 11.5 0.6 1.2 -9.0 -5.4 7.5 11.9 1973 4.9 16.0 5.5 -12.5 -1.2 7.6 2.1 3.0 -0.1 -7.0 -8.6 -0.2 1974 21.2 7.4 -0.9 -2.0 0.1 -0.2 4.5 0.3 5.1 -3.7 4.5 11.8 1975 12.2 -5.5 -3.7 1.1 -4.2 -3.1 2.0 -0.4 7.8 -5.6 6.4 -1.2 1976 5.6 9.9 12.8 2.6 11.1 3.6 -4.7 -4.3 -15.1 7.1 5.9 -15.9 1977 -12.3 -9.4 -4.8 3.5 -3.1 -3.8 0.4 -2.4 -1.8 4.4 -1.7 -6.9 1978 10.3 -24.1 16.3 -9.6 5.4 3.8 -5.1 -5.0 1.1 0.0 14.2 -18.6 1979 -17.3 -8.3 6.4 -6.7 -1.2 2.9 1.6 0.1 2.0 -0.3 8.5 10.3 1980 -12.6 1.2 -2.3 0.8 -7.5 3.8 -3.9 -5.3 3.9 -10.2 -14.9 7.5 1981 6.3 7.9 -9.7 -5.3 0.0 -4.9 3.9 2.0 -1.3 -1.2 -5.0 -11.7 1982 -9.8 12.5 14.3 0.3 1.8 -10.2 -0.3 6.2 3.9 4.8 12.3 14.2 1983 23.3 -10.6 11.3 -5.2 -2.6 -0.5 1.8 5.0 -6.3 7.4 -16.8 1.5 1984 25.2 12.1 -14.9 -1.1 5.6 0.6 -2.6 2.5 1.6 4.4 2.0 9.7 1985 -21.0 -13.6 0.6 0.3 -2.8 -2.0 1.8 1.8 -5.6 -0.2 -14.8 -11.0 1986 15.7 -25.4 24.1 -0.6 8.0 2.7 2.5 -9.7 -9.4 18.2 17.2 11.3 1987 -22.8 -7.2 -2.4 6.1 -5.2 -4.9 0.7 -9.1 0.5 3.0 0.2 -13.3 1988 6.5 0.6 -3.2 -11.8 -2.0 3.0 2.0 4.9 2.9 -7.8 -10.6 3.9 1989 20.4 24.5 19.3 3.2 3.7 -2.6 1.1 8.4 2.9 3.5 -7.3 -16.5 1990 25.4 26.4 14.5 16.0 -6.2 2.5 0.3 3.3 0.6 1.3 -9.2 10.6 1991 6.6 0.0 -2.6 5.0 4.0 -0.7 -2.1 7.0 0.6 -4.7 9.2 3.0 1992 -6.8 15.5 13.9 7.1 4.2 1.1 1.2 6.7 0.5 -8.5 16.1 7.8 1993 17.4 1.6 8.1 6.3 -12.6 -3.0 -1.7 -0.1 -7.7 -20.5 14.1 11.3 1994 12.2 -5.6 27.1 5.9 -0.6 8.3 4.0 -1.8 -1.2 -6.5 1.3 11.4 1995 13.4 16.3 10.3 -8.6 -5.1 -6.5 -3.3 -1.3 -0.8 -1.6 -18.7 -23.0 1996 -10.3 5.0 -17.4 -9.6 -6.5 1.7 4.8 1.4 1.7 7.4 2.5 -21.8 1997 -13.3 28.0 6.3 -6.6 -7.3 -9.6 2.6 3.0 -0.1 -11.9 -1.5 -5.6 1998 -4.7 6.5 1.6 1.1 0.0 -5.4 2.0 4.8 -8.7 5.0 3.5 9.7 1999 11.4 17.6 -2.0 -4.2 4.3 5.0 -1.5 -11.8 6.2 0.2 5.2 10.4 2000 3.1 23.0 0.1 -11.1 7.4 -2.0 -5.5 1.3 2.1 14.2 -0.1 -12.4 2001 1.0 -5.4 -10.4 5.7 -0.7 -4.3 0.5 2.3 -8.3 3.8 8.5 -21.7 2002 5.3 11.9 2.1 11.0 6.5 4.9 5.1 1.2 -13.0 -12.0 4.4 -12.4 2003 1.4 9.2 2.1 -8.2 3.3 -0.8 1.0 -5.9 -1.0 -4.9 7.0 -7.4 2004 -0.9 -13.4 6.0 8.3 2.7 -4.3 0.9 -4.0 7.8 -9.2 -3.0 17.3 2005 9.4 -6.4 -20.1 0.8 -4.9 -5.3 0.8 5.4 3.6-9999.0-9999.0-9999.0