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% 15.30%
1911 7.40% 16.60%
1912 28.50% 10.60%
1913 2.40% 12.00%
1914 4.80% 24.90%
1915 4.20% 25.90%
1916 6.40% 20.50%
1917 6.10% 18.80%
1918 0.00% 14.50%
1919 8.70% 16.60%
1920 4.20% 4.10%
1921 0.00% 20.60%
1922 19.40% 4.40%
1923 8.30% 18.70%
1924 4.30% 8.30%
1925 0.00% 22.20%
1926 6.30% 6.00%
1927 6.00% 14.80%
1928 15.00% 0.00%
1929 36.00% 0.00%
1930 4.20% 9.80%
1931 0.00% 16.40%
1932 26.10% 1.90%
1933 0.00% 13.50%
1934 4.00% 7.70%
1935 2.00% 6.20%
1936 10.80% 2.20%
1937 27.00% 0.00%
1938 1.90% 17.80%
1939 4.00% 6.00%
1940 1.90% 13.60%
1941 2.20% 35.90%
1942 3.90% 5.60%
1943 0.00% 46.70%
1944 6.20% 2.00%
1945 5.90% 0.00%
1946 7.90% 4.00%
1947 24.00% 1.90%
1948 26.40% 0.00%
1949 15.80% 0.00%
1950 7.60% 11.90%
1951 0.00% 18.40%
1952 0.00% 13.70%
1953 15.70% 13.10%
1954 0.00% 50.90%
1955 0.00% 17.50%
1956 3.70% 16.10%
1957 34.50% 0.00%
1958 9.70% 5.70%
1959 28.60% 1.90%
1960 6.00% 7.60%
1961 13.40% 9.90%
1962 7.60% 0.00%
1963 0.00% 14.00%
1964 18.10% 1.90%
1965 2.10% 4.00%
1966 5.90% 3.70%
1967 0.00% 6.00%
1968 0.00% 11.90%
1969 4.40% 6.20%
1970 4.10% 12.70%
1971 27.70% 0.00%
1972 23.60% 4.10%
1973 17.90% 4.60%
1974 25.60% 2.00%
1975 50.00% 0.00%
1976 4.00% 5.90%
1977 4.00% 3.90%
1978 2.10% 12.80%
1979 5.90% 0.00%
1980 1.90% 3.80%
1981 0.00% 21.40%
1982 34.50% 2.10%
1983 10.50% 2.00%
1984 1.90% 16.00%
1985 0.00% 11.60%
1986 4.10% 9.70%
1987 2.10% 7.80%
1988 2.00% 7.70%
1989 46.30% 2.00%
1990 1.90% 24.30%
1991 22.50% 6.00%
1992 35.80% 2.00%
1993 4.00% 7.90%
1994 29.00% 1.90%
1995 4.00% 6.00%
1996 17.10% 6.00%
1997 5.90% 4.00%
1998 5.70% 14.00%
1999 0.00% 12.10%
2000 1.80% 16.30%
2001 2.00% 11.50%
2002 8.10% 2.20%
2003 43.10% 0.00%
2004 16.10% 0.00%
2005 6.70% 0.00%
2006 3.90% 25.40%
2007 0.00% 38.80%
2008 2.20% 4.10%
2009 32.10% 4.10%
2010 0.00% 29.60%
2011 4.40% 11.40%
2012 8.30% 0.00%
2013 46.60% 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.