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% 26.80%
1911 0.00% 42.60%
1912 0.00% 24.60%
1913 0.00% 8.80%
1914 0.00% 33.70%
1915 8.80% 9.00%
1916 0.00% 4.40%
1917 8.20% 0.00%
1918 0.00% 50.30%
1919 0.00% 18.30%
1920 0.00% 5.20%
1921 0.00% 5.10%
1922 0.00% 10.20%
1923 0.00% 8.90%
1924 0.00% 85.30%
1925 4.60% 17.70%
1926 0.00% 36.20%
1927 5.10% 0.00%
1928 0.00% 0.00%
1929 0.00% 9.10%
1930 0.00% 9.50%
1931 0.00% 20.50%
1932 13.10% 0.00%
1933 12.20% 0.00%
1934 0.00% 46.30%
1935 0.00% 16.30%
1936 0.00% 17.40%
1937 4.30% 0.00%
1938 0.00% 0.00%
1939 0.00% 48.00%
1940 0.00% 8.90%
1941 4.10% 0.00%
1942 0.00% 0.00%
1943 0.00% 0.00%
1944 0.00% 8.90%
1945 37.50% 0.00%
1946 0.00% 0.00%
1947 0.00% 20.40%
1948 37.40% 0.00%
1949 0.00% 4.00%
1950 8.40% 4.40%
1951 0.00% 45.90%
1952 8.30% 12.70%
1953 16.80% 0.00%
1954 0.00% 33.60%
1955 8.60% 0.00%
1956 0.00% 12.70%
1957 37.70% 0.00%
1958 13.60% 0.00%
1959 4.00% 0.00%
1960 45.30% 0.00%
1961 28.50% 0.00%
1962 0.00% 0.00%
1963 0.00% 0.00%
1964 0.00% 24.90%
1965 4.60% 34.70%
1966 0.00% 33.80%
1967 8.60% 4.20%
1968 0.00% 9.20%
1969 0.00% 16.80%
1970 0.00% 4.30%
1971 0.00% 0.00%
1972 12.80% 9.10%
1973 0.00% 25.90%
1974 30.90% 0.00%
1975 4.30% 0.00%
1976 4.20% 4.40%
1977 4.10% 0.00%
1978 4.10% 0.00%
1979 0.00% 4.00%
1980 8.40% 0.00%
1981 8.70% 0.00%
1982 4.50% 8.70%
1983 22.80% 0.00%
1984 60.20% 0.00%
1985 0.00% 0.00%
1986 8.10% 0.00%
1987 0.00% 0.00%
1988 12.50% 0.00%
1989 42.00% 0.00%
1990 4.30% 0.00%
1991 26.50% 0.00%
1992 0.00% 33.30%
1993 58.80% 0.00%
1994 0.00% 0.00%
1995 18.20% 0.00%
1996 0.00% 0.00%
1997 16.30% 0.00%
1998 32.80% 0.00%
1999 4.60% 9.10%
2000 0.00% 0.00%
2001 0.00% 0.00%
2002 0.00% 0.00%
2003 55.00% 0.00%
2004 0.00% 4.30%
2005 46.40% 0.00%
2006 23.10% 0.00%
2007 0.00% 13.30%
2008 12.40% 0.00%
2009 0.00% 0.00%
2010 21.90% 0.00%
2011 89.20% 0.00%
2012 45.30% 0.00%
2013 8.90% 9.30%

*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.