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% 77.60%
1911 11.90% 9.60%
1912 0.00% 25.40%
1913 2.50% 35.20%
1914 2.20% 20.60%
1915 9.60% 4.40%
1916 7.30% 12.00%
1917 0.00% 28.60%
1918 4.70% 16.10%
1919 4.60% 9.00%
1920 5.10% 15.50%
1921 0.00% 19.60%
1922 2.10% 13.10%
1923 0.00% 28.20%
1924 2.20% 8.40%
1925 2.20% 17.90%
1926 6.90% 13.90%
1927 9.50% 7.10%
1928 2.30% 11.60%
1929 0.00% 16.20%
1930 0.00% 15.60%
1931 0.00% 24.80%
1932 0.00% 8.80%
1933 2.20% 24.70%
1934 0.00% 33.60%
1935 4.40% 4.50%
1936 2.10% 11.20%
1937 0.00% 13.40%
1938 19.50% 4.40%
1939 0.00% 28.70%
1940 7.10% 2.40%
1941 11.60% 2.40%
1942 5.10% 0.00%
1943 0.00% 4.80%
1944 6.70% 2.20%
1945 8.80% 0.00%
1946 4.40% 9.00%
1947 5.30% 2.80%
1948 2.40% 18.10%
1949 4.40% 26.00%
1950 6.50% 9.30%
1951 42.00% 2.10%
1952 0.00% 27.30%
1953 2.10% 11.70%
1954 10.70% 8.80%
1955 6.40% 16.30%
1956 4.30% 9.00%
1957 0.00% 4.50%
1958 0.00% 40.50%
1959 9.40% 2.30%
1960 2.20% 8.70%
1961 2.30% 15.00%
1962 4.30% 4.30%
1963 2.30% 25.70%
1964 0.00% 22.10%
1965 24.00% 0.00%
1966 0.00% 28.90%
1967 6.70% 4.30%
1968 12.90% 2.20%
1969 4.30% 0.00%
1970 2.10% 2.20%
1971 10.40% 4.50%
1972 8.80% 0.00%
1973 18.60% 0.00%
1974 2.30% 2.30%
1975 10.90% 0.00%
1976 0.00% 58.40%
1977 46.10% 0.00%
1978 0.00% 2.10%
1979 8.50% 2.20%
1980 7.00% 7.30%
1981 0.00% 4.50%
1982 33.60% 0.00%
1983 40.50% 0.00%
1984 18.30% 2.10%
1985 31.30% 0.00%
1986 11.60% 0.00%
1987 0.00% 2.20%
1988 2.40% 9.70%
1989 2.20% 11.20%
1990 6.70% 4.20%
1991 15.20% 0.00%
1992 4.60% 4.40%
1993 48.60% 2.10%
1994 4.30% 2.10%
1995 10.90% 4.30%
1996 15.30% 2.20%
1997 6.70% 6.40%
1998 27.50% 4.40%
1999 2.30% 2.10%
2000 24.20% 0.00%
2001 15.40% 2.20%
2002 6.30% 2.10%
2003 4.30% 4.20%
2004 37.60% 0.00%
2005 15.20% 2.20%
2006 11.10% 0.00%
2007 11.40% 0.00%
2008 58.90% 0.00%
2009 33.80% 0.00%
2010 21.00% 0.00%
2011 24.50% 2.60%
2012 2.30% 5.00%
2013 51.10% 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.