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% 34.10%
1911 4.20% 7.60%
1912 7.50% 3.80%
1913 17.10% 17.40%
1914 42.00% 9.90%
1915 3.30% 16.80%
1916 0.00% 11.80%
1917 0.00% 24.40%
1918 6.20% 0.00%
1919 3.70% 13.60%
1920 7.00% 20.60%
1921 35.00% 3.30%
1922 3.40% 20.30%
1923 18.20% 3.10%
1924 0.00% 46.70%
1925 14.90% 0.00%
1926 0.00% 19.30%
1927 25.30% 0.00%
1928 5.90% 15.70%
1929 6.20% 6.00%
1930 19.10% 6.10%
1931 15.80% 8.70%
1932 0.00% 0.00%
1933 9.40% 2.80%
1934 0.00% 6.10%
1935 3.10% 8.60%
1936 15.60% 9.50%
1937 0.00% 6.60%
1938 2.90% 9.20%
1939 3.30% 49.40%
1940 0.00% 9.60%
1941 9.20% 0.00%
1942 0.00% 28.30%
1943 3.20% 9.70%
1944 0.00% 29.30%
1945 12.10% 0.00%
1946 6.30% 2.90%
1947 3.20% 0.00%
1948 0.00% 12.60%
1949 9.60% 3.30%
1950 0.00% 8.80%
1951 18.10% 0.00%
1952 0.00% 0.00%
1953 6.50% 3.30%
1954 2.80% 5.80%
1955 18.20% 0.00%
1956 0.00% 9.10%
1957 30.40% 0.00%
1958 6.50% 13.10%
1959 22.00% 0.00%
1960 0.00% 14.90%
1961 24.40% 0.00%
1962 0.00% 18.30%
1963 14.60% 0.00%
1964 0.00% 9.50%
1965 32.50% 3.20%
1966 6.30% 5.80%
1967 47.90% 0.00%
1968 9.30% 0.00%
1969 3.20% 0.00%
1970 9.00% 3.00%
1971 3.20% 6.00%
1972 13.00% 3.20%
1973 0.00% 0.00%
1974 0.00% 11.80%
1975 0.00% 19.00%
1976 0.00% 12.60%
1977 0.00% 0.00%
1978 0.00% 28.90%
1979 0.00% 17.40%
1980 0.00% 27.10%
1981 14.80% 5.70%
1982 9.30% 3.30%
1983 27.70% 6.50%
1984 60.80% 0.00%
1985 0.00% 9.70%
1986 27.30% 6.10%
1987 3.10% 3.30%
1988 32.90% 3.30%
1989 0.00% 6.60%
1990 6.30% 0.00%
1991 15.10% 12.50%
1992 21.30% 0.00%
1993 6.00% 15.50%
1994 0.00% 15.60%
1995 5.80% 12.60%
1996 18.10% 9.20%
1997 9.40% 6.80%
1998 15.10% 9.70%
1999 34.40% 0.00%
2000 13.00% 0.00%
2001 3.50% 0.00%
2002 0.00% 36.30%
2003 0.00% 3.10%
2004 9.00% 0.00%
2005 6.20% 6.60%
2006 18.10% 0.00%
2007 0.00% 10.30%
2008 7.50% 3.50%
2009 3.80% 4.10%
2010 0.00% 3.40%
2011 0.00% 5.00%
2012 8.00% 14.90%
2013 9.30% 0.00%
2014 10.10% 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.