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 8.20%
1911 13.90%
1912 6.00%
1913 7.30%
1914 17.70%
1915 12.80%
1916 8.30%
1917 2.50%
1918 8.40%
1919 7.30%
1920 7.10%
1921 15.00%
1922 6.90%
1923 10.50%
1924 1.20%
1925 7.80%
1926 2.40%
1927 9.20%
1928 9.10%
1929 7.30%
1930 7.90%
1931 7.00%
1932 5.60%
1933 17.40%
1934 8.00%
1935 12.80%
1936 13.70%
1937 1.10%
1938 18.80%
1939 3.30%
1940 5.80%
1941 12.90%
1942 11.50%
1943 5.70%
1944 2.30%
1945 11.70%
1946 11.80%
1947 3.00%
1948 8.20%
1949 8.40%
1950 9.10%
1951 10.10%
1952 7.00%
1953 12.70%
1954 9.20%
1955 10.00%
1956 1.20%
1957 13.60%
1958 5.70%
1959 6.90%
1960 5.70%
1961 13.80%
1962 7.80%
1963 9.20%
1964 13.90%
1965 18.00%
1966 14.20%
1967 11.50%
1968 6.70%
1969 7.80%
1970 3.40%
1971 9.00%
1972 5.50%
1973 18.40%
1974 15.90%
1975 6.70%
1976 7.60%
1977 7.60%
1978 7.90%
1979 15.10%
1980 14.20%
1981 10.50%
1982 6.00%
1983 12.70%
1984 5.80%
1985 19.60%
1986 15.80%
1987 6.90%
1988 6.60%
1989 9.20%
1990 11.50%
1991 16.40%
1992 3.70%
1993 5.90%
1994 8.30%
1995 21.40%
1996 21.50%
1997 10.90%
1998 34.30%
1999 13.80%
2000 5.90%
2001 16.10%
2002 15.60%
2003 10.00%
2004 5.80%
2005 14.20%
2006 12.90%
2007 18.80%
2008 23.00%
2009 18.20%
2010 15.20%
2011 14.70%
2012 12.70%
2013 16.50%

*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.