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% 65.10%
1911 8.30% 11.50%
1912 0.00% 21.50%
1913 3.60% 14.10%
1914 33.10% 10.50%
1915 3.40% 10.40%
1916 0.00% 13.60%
1917 0.00% 30.70%
1918 13.80% 3.40%
1919 10.70% 9.90%
1920 3.70% 21.20%
1921 7.40% 17.20%
1922 3.80% 22.10%
1923 9.80% 6.70%
1924 0.00% 53.80%
1925 3.20% 13.50%
1926 17.50% 6.50%
1927 3.50% 0.00%
1928 3.20% 16.90%
1929 0.00% 19.40%
1930 7.00% 6.50%
1931 20.80% 12.70%
1932 0.00% 16.50%
1933 0.00% 12.60%
1934 0.00% 32.10%
1935 7.10% 6.70%
1936 3.40% 6.90%
1937 0.00% 7.00%
1938 3.10% 6.70%
1939 0.00% 29.50%
1940 10.00% 0.00%
1941 68.20% 0.00%
1942 3.40% 14.70%
1943 0.00% 12.90%
1944 3.40% 6.60%
1945 9.50% 10.30%
1946 10.20% 3.20%
1947 7.20% 3.80%
1948 0.00% 26.60%
1949 24.30% 0.00%
1950 0.00% 44.20%
1951 9.80% 0.00%
1952 3.30% 0.00%
1953 0.00% 38.90%
1954 0.00% 15.70%
1955 3.10% 6.70%
1956 0.00% 52.80%
1957 61.20% 0.00%
1958 25.60% 3.50%
1959 6.50% 6.30%
1960 6.50% 0.00%
1961 19.10% 0.00%
1962 3.40% 6.30%
1963 9.20% 6.50%
1964 0.00% 13.20%
1965 38.60% 0.00%
1966 0.00% 15.80%
1967 6.20% 3.30%
1968 3.30% 0.00%
1969 20.30% 0.00%
1970 6.30% 13.90%
1971 3.10% 3.40%
1972 0.00% 3.40%
1973 3.20% 3.50%
1974 0.00% 9.70%
1975 6.90% 13.90%
1976 0.00% 12.90%
1977 0.00% 3.20%
1978 32.80% 10.10%
1979 0.00% 0.00%
1980 6.70% 16.70%
1981 9.40% 0.00%
1982 26.60% 0.00%
1983 55.20% 0.00%
1984 32.20% 0.00%
1985 12.90% 0.00%
1986 24.40% 0.00%
1987 30.80% 0.00%
1988 3.30% 0.00%
1989 3.30% 34.10%
1990 23.30% 0.00%
1991 12.90% 3.30%
1992 44.10% 0.00%
1993 23.30% 0.00%
1994 6.80% 0.00%
1995 12.70% 3.40%
1996 9.80% 10.70%
1997 27.90% 0.00%
1998 32.80% 3.40%
1999 3.30% 3.50%
2000 3.20% 3.50%
2001 3.60% 3.60%
2002 0.00% 24.10%
2003 0.00% 10.70%
2004 10.40% 0.00%
2005 3.20% 0.00%
2006 0.00% 3.60%
2007 6.30% 9.60%
2008 3.70% 8.00%
2009 7.50% 8.20%
2010 3.40% 0.00%
2011 9.70% 4.80%
2012 0.00% 24.30%
2013 8.90% 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.