U.S. Climate Extremes Index (CEI)

NCDC transitioned to the nClimDiv dataset on Thursday, March 13, 2014. This was coincident with the release of the February 2014 monthly monitoring report. For details on this transition, please visit our public FTP site and our U.S. Climate Divisional Database site.

Graph

Choose a period/season and an indicator from the options below and click "Plot" to create a time series graph. Note that the sixth indicator (Step 6) is not calculated for the spring (March-May), winter (December-February) and cold (October-March) seasons since most months during these periods are outside of the traditional hurricane season.



Move mouse towards an axis until highlighted. Left-click mouse to pan. Shift key + left-click to zoom.

Year Percent
1910 11.70%
1911 3.80%
1912 8.10%
1913 4.20%
1914 2.00%
1915 4.50%
1916 6.10%
1917 0.00%
1918 11.50%
1919 11.90%
1920 3.90%
1921 7.60%
1922 13.10%
1923 7.60%
1924 0.00%
1925 3.80%
1926 5.70%
1927 14.80%
1928 7.60%
1929 11.40%
1930 0.00%
1931 9.40%
1932 3.80%
1933 13.20%
1934 9.30%
1935 1.90%
1936 13.30%
1937 15.40%
1938 9.20%
1939 10.90%
1940 7.40%
1941 5.50%
1942 3.70%
1943 0.00%
1944 9.40%
1945 5.90%
1946 3.90%
1947 3.70%
1948 7.50%
1949 7.40%
1950 27.60%
1951 1.90%
1952 5.60%
1953 1.80%
1954 11.00%
1955 7.60%
1956 0.00%
1957 9.50%
1958 19.20%
1959 5.50%
1960 5.60%
1961 11.00%
1962 5.80%
1963 3.80%
1964 11.30%
1965 9.70%
1966 11.40%
1967 0.00%
1968 5.80%
1969 13.30%
1970 11.30%
1971 7.50%
1972 1.90%
1973 13.80%
1974 3.90%
1975 5.90%
1976 15.20%
1977 13.30%
1978 6.00%
1979 9.50%
1980 5.70%
1981 12.60%
1982 15.40%
1983 17.20%
1984 5.80%
1985 11.90%
1986 16.00%
1987 5.50%
1988 11.60%
1989 11.20%
1990 36.90%
1991 7.50%
1992 4.00%
1993 17.30%
1994 14.30%
1995 10.00%
1996 32.50%
1997 2.00%
1998 24.30%
1999 9.30%
2000 23.00%
2001 7.90%
2002 22.10%
2003 18.90%
2004 19.80%
2005 12.00%
2006 13.50%
2007 22.70%
2008 34.90%
2009 20.40%
2010 28.50%
2011 23.40%
2012 14.30%
2013 29.70%

*As of September 2005, the fourth and fifth indicators are computed with data from one station per each grid box rather than multiple stations. This was done to eliminate many of the artificial extremes which resulted from a changing number of available stations over time. Therefore, the percentages in the step 4 and 5 graphs above will likely be significantly different from the percentages calculated prior to the changes implemented in September 2005.

View CEI Data Files

Limitations: Statistics for the most recent period/season are computed from a fraction of the U.S. which has data available at that time. Extreme percentage values can and will likely change as final quality controlled data become available and fill in the data gaps.