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% 12.40%
1911 0.00% 11.00%
1912 0.00% 0.00%
1913 55.20% 0.00%
1914 0.00% 0.00%
1915 0.00% 0.00%
1916 0.00% 11.10%
1917 0.00% 13.60%
1918 0.00% 0.00%
1919 0.00% 42.10%
1920 12.30% 0.00%
1921 0.00% 12.40%
1922 0.00% 0.00%
1923 0.00% 0.00%
1924 0.00% 24.80%
1925 22.00% 10.50%
1926 0.00% 0.00%
1927 0.00% 0.00%
1928 0.00% 9.40%
1929 33.30% 0.00%
1930 0.00% 0.00%
1931 10.30% 0.00%
1932 0.00% 0.00%
1933 11.40% 10.50%
1934 11.20% 0.00%
1935 0.00% 0.00%
1936 40.10% 0.00%
1937 0.00% 0.00%
1938 19.90% 0.00%
1939 0.00% 0.00%
1940 0.00% 0.00%
1941 10.50% 0.00%
1942 0.00% 0.00%
1943 0.00% 0.00%
1944 20.60% 0.00%
1945 0.00% 9.40%
1946 0.00% 0.00%
1947 39.50% 0.00%
1948 0.00% 0.00%
1949 0.00% 19.30%
1950 0.00% 0.00%
1951 0.00% 9.40%
1952 19.90% 0.00%
1953 30.10% 0.00%
1954 19.30% 0.00%
1955 0.00% 9.90%
1956 0.00% 0.00%
1957 0.00% 0.00%
1958 59.00% 0.00%
1959 0.00% 0.00%
1960 0.00% 0.00%
1961 0.00% 0.00%
1962 0.00% 0.00%
1963 0.00% 0.00%
1964 39.90% 0.00%
1965 40.30% 0.00%
1966 10.00% 10.00%
1967 10.20% 0.00%
1968 9.90% 0.00%
1969 10.00% 0.00%
1970 9.90% 0.00%
1971 0.00% 0.00%
1972 11.70% 0.00%
1973 0.00% 0.00%
1974 0.00% 0.00%
1975 9.90% 0.00%
1976 77.20% 0.00%
1977 10.30% 0.00%
1978 10.50% 11.00%
1979 0.00% 0.00%
1980 0.00% 0.00%
1981 0.00% 22.00%
1982 19.90% 0.00%
1983 20.40% 0.00%
1984 20.60% 0.00%
1985 0.00% 0.00%
1986 0.00% 0.00%
1987 0.00% 0.00%
1988 9.90% 0.00%
1989 12.30% 0.00%
1990 0.00% 0.00%
1991 10.20% 0.00%
1992 30.30% 0.00%
1993 0.00% 0.00%
1994 0.00% 19.90%
1995 20.00% 0.00%
1996 0.00% 0.00%
1997 39.50% 0.00%
1998 0.00% 0.00%
1999 0.00% 0.00%
2000 0.00% 11.00%
2001 0.00% 11.00%
2002 0.00% 12.20%
2003 0.00% 0.00%
2004 0.00% 0.00%
2005 11.00% 0.00%
2006 0.00% 21.90%
2007 0.00% 0.00%
2008 0.00% 19.90%
2009 33.90% 0.00%
2010 0.00% 0.00%
2011 41.10% 0.00%
2012 11.80% 0.00%
2013 0.00% 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.