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.

Download: Wet Data | Dry Data
Year Wet Dry
1910 0.00% 32.60%
1911 7.60% 7.80%
1912 8.10% 16.50%
1913 4.10% 10.70%
1914 0.00% 28.10%
1915 23.70% 2.20%
1916 4.00% 14.20%
1917 0.00% 23.10%
1918 0.00% 15.00%
1919 0.00% 9.80%
1920 0.00% 21.00%
1921 1.90% 0.00%
1922 2.00% 18.80%
1923 7.70% 3.70%
1924 13.20% 3.80%
1925 0.00% 11.70%
1926 33.70% 1.90%
1927 18.60% 0.00%
1928 1.90% 3.70%
1929 27.00% 0.00%
1930 0.00% 27.40%
1931 1.90% 5.60%
1932 0.00% 9.50%
1933 1.90% 9.30%
1934 0.00% 31.50%
1935 11.30% 0.00%
1936 0.00% 43.90%
1937 13.70% 3.90%
1938 7.20% 9.30%
1939 3.70% 14.70%
1940 3.60% 3.70%
1941 9.00% 16.70%
1942 18.30% 3.60%
1943 7.30% 13.10%
1944 3.60% 5.60%
1945 40.30% 0.00%
1946 0.00% 7.80%
1947 1.90% 1.90%
1948 3.80% 1.80%
1949 11.30% 0.00%
1950 22.40% 3.70%
1951 31.60% 0.00%
1952 0.00% 11.50%
1953 0.00% 39.90%
1954 1.80% 11.20%
1955 0.00% 17.20%
1956 7.40% 20.30%
1957 15.30% 0.00%
1958 1.90% 9.70%
1959 1.80% 3.80%
1960 2.00% 9.80%
1961 7.50% 1.80%
1962 3.80% 11.20%
1963 0.00% 54.30%
1964 1.80% 14.90%
1965 1.90% 3.90%
1966 0.00% 16.70%
1967 11.00% 3.70%
1968 3.90% 1.90%
1969 1.90% 3.80%
1970 7.40% 3.80%
1971 0.00% 18.70%
1972 32.60% 5.80%
1973 37.40% 0.00%
1974 25.50% 3.80%
1975 21.50% 2.00%
1976 0.00% 36.30%
1977 13.20% 1.90%
1978 6.00% 0.00%
1979 24.80% 0.00%
1980 1.90% 13.50%
1981 9.40% 3.70%
1982 19.30% 0.00%
1983 9.10% 5.70%
1984 28.40% 0.00%
1985 27.30% 6.10%
1986 2.00% 6.10%
1987 0.00% 7.60%
1988 0.00% 38.20%
1989 3.70% 9.20%
1990 1.90% 5.60%
1991 1.80% 9.30%
1992 23.40% 6.00%
1993 46.40% 2.00%
1994 0.00% 17.80%
1995 0.00% 22.50%
1996 20.40% 4.20%
1997 10.30% 2.00%
1998 22.90% 7.30%
1999 0.00% 29.70%
2000 5.80% 3.70%
2001 3.80% 3.90%
2002 4.20% 15.70%
2003 27.10% 3.80%
2004 23.60% 0.00%
2005 2.00% 5.90%
2006 7.60% 3.80%
2007 5.80% 5.80%
2008 30.60% 0.00%
2009 35.10% 6.00%
2010 2.10% 16.30%
2011 41.50% 4.60%
2012 2.30% 14.10%
2013 11.50% 0.00%

*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.