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% 32.70%
1911 4.00% 7.30%
1912 10.90% 3.70%
1913 16.50% 16.80%
1914 40.50% 9.60%
1915 3.20% 16.20%
1916 0.00% 11.40%
1917 0.00% 23.70%
1918 6.20% 0.00%
1919 3.60% 13.10%
1920 6.80% 19.90%
1921 33.90% 3.20%
1922 3.30% 19.60%
1923 18.20% 3.10%
1924 0.00% 45.20%
1925 14.90% 0.00%
1926 0.00% 19.30%
1927 28.40% 0.00%
1928 5.70% 15.20%
1929 6.00% 5.80%
1930 18.50% 5.90%
1931 15.80% 8.70%
1932 0.00% 0.00%
1933 9.10% 2.70%
1934 0.00% 5.90%
1935 3.00% 8.40%
1936 15.60% 9.50%
1937 0.00% 6.40%
1938 2.80% 8.90%
1939 3.20% 47.80%
1940 0.00% 9.30%
1941 8.90% 0.00%
1942 0.00% 27.40%
1943 3.10% 9.40%
1944 0.00% 31.60%
1945 14.60% 0.00%
1946 6.10% 2.80%
1947 3.20% 0.00%
1948 0.00% 12.30%
1949 9.30% 3.10%
1950 0.00% 8.60%
1951 20.70% 0.00%
1952 0.00% 0.00%
1953 6.30% 3.20%
1954 2.80% 5.60%
1955 20.70% 0.00%
1956 0.00% 11.90%
1957 29.50% 0.00%
1958 6.20% 16.10%
1959 21.30% 0.00%
1960 0.00% 14.90%
1961 24.40% 0.00%
1962 0.00% 20.90%
1963 14.10% 0.00%
1964 3.10% 9.20%
1965 31.40% 3.10%
1966 6.10% 5.60%
1967 49.20% 0.00%
1968 9.00% 0.00%
1969 3.10% 0.00%
1970 8.70% 2.90%
1971 3.10% 5.80%
1972 15.50% 3.10%
1973 0.00% 0.00%
1974 0.00% 11.40%
1975 0.00% 18.40%
1976 0.00% 12.20%
1977 0.00% 0.00%
1978 0.00% 27.90%
1979 0.00% 16.80%
1980 0.00% 26.10%
1981 17.40% 5.50%
1982 12.30% 3.20%
1983 26.80% 6.30%
1984 62.00% 0.00%
1985 0.00% 9.40%
1986 26.40% 5.90%
1987 3.00% 3.20%
1988 31.70% 3.20%
1989 0.00% 6.40%
1990 9.20% 0.00%
1991 17.60% 12.10%
1992 20.70% 0.00%
1993 5.80% 15.00%
1994 0.00% 15.10%
1995 5.60% 12.20%
1996 17.60% 8.90%
1997 9.10% 6.50%
1998 17.80% 9.40%
1999 36.50% 0.00%
2000 12.60% 0.00%
2001 3.40% 0.00%
2002 0.00% 38.50%
2003 0.00% 3.00%
2004 8.70% 0.00%
2005 6.00% 6.40%
2006 17.40% 0.00%
2007 0.00% 9.90%
2008 7.30% 3.40%
2009 3.70% 4.00%
2010 3.10% 3.30%
2011 0.00% 4.70%
2012 7.70% 14.30%
2013 6.40% 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.