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% 27.50%
1911 13.70% 32.70%
1912 0.00% 13.40%
1913 5.00% 25.00%
1914 5.00% 19.80%
1915 0.00% 28.60%
1916 14.90% 9.90%
1917 5.10% 10.40%
1918 0.00% 5.20%
1919 0.00% 5.60%
1920 0.00% 10.10%
1921 0.00% 21.10%
1922 0.00% 39.00%
1923 0.00% 35.00%
1924 0.00% 42.00%
1925 5.40% 5.50%
1926 5.10% 5.00%
1927 4.80% 5.00%
1928 0.00% 9.50%
1929 8.90% 4.60%
1930 0.00% 47.80%
1931 0.00% 33.80%
1932 0.00% 30.40%
1933 0.00% 23.50%
1934 0.00% 33.30%
1935 9.50% 14.10%
1936 9.30% 4.70%
1937 8.90% 4.50%
1938 9.10% 0.00%
1939 9.10% 13.50%
1940 13.80% 4.50%
1941 0.00% 45.40%
1942 9.50% 0.00%
1943 4.70% 4.60%
1944 0.00% 28.30%
1945 62.10% 0.00%
1946 0.00% 19.30%
1947 9.00% 9.10%
1948 9.40% 8.80%
1949 0.00% 4.60%
1950 32.40% 0.00%
1951 8.80% 0.00%
1952 0.00% 9.00%
1953 0.00% 0.00%
1954 22.20% 4.70%
1955 0.00% 9.80%
1956 18.40% 0.00%
1957 0.00% 26.80%
1958 0.00% 0.00%
1959 0.00% 0.00%
1960 0.00% 0.00%
1961 0.00% 4.40%
1962 0.00% 13.80%
1963 0.00% 18.50%
1964 0.00% 13.50%
1965 0.00% 0.00%
1966 0.00% 9.00%
1967 0.00% 0.00%
1968 4.50% 4.70%
1969 0.00% 4.50%
1970 18.40% 0.00%
1971 0.00% 9.00%
1972 52.70% 0.00%
1973 4.80% 0.00%
1974 14.10% 4.90%
1975 19.30% 0.00%
1976 13.50% 4.70%
1977 13.40% 0.00%
1978 0.00% 18.70%
1979 18.30% 4.50%
1980 0.00% 9.20%
1981 4.70% 0.00%
1982 0.00% 4.70%
1983 0.00% 0.00%
1984 19.20% 0.00%
1985 31.70% 0.00%
1986 5.10% 0.00%
1987 0.00% 4.50%
1988 4.80% 9.70%
1989 33.40% 0.00%
1990 9.00% 0.00%
1991 0.00% 18.20%
1992 31.90% 4.40%
1993 18.80% 0.00%
1994 4.60% 4.60%
1995 0.00% 13.50%
1996 40.70% 0.00%
1997 18.00% 4.40%
1998 4.40% 4.50%
1999 0.00% 27.50%
2000 13.60% 9.30%
2001 4.60% 23.10%
2002 9.50% 9.50%
2003 65.30% 0.00%
2004 45.50% 0.00%
2005 18.00% 0.00%
2006 23.50% 5.00%
2007 0.00% 15.20%
2008 59.80% 5.00%
2009 21.20% 5.20%
2010 0.00% 16.00%
2011 66.40% 0.00%
2012 10.50% 10.80%
2013 17.50% 5.90%

*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.