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% 67.30%
1911 11.00% 23.40%
1912 9.70% 17.30%
1913 8.80% 15.90%
1914 9.60% 14.30%
1915 27.50% 0.00%
1916 2.20% 9.30%
1917 8.80% 17.60%
1918 8.90% 14.50%
1919 2.30% 27.50%
1920 8.60% 10.30%
1921 0.00% 17.90%
1922 8.00% 14.10%
1923 2.20% 10.00%
1924 2.00% 17.70%
1925 2.00% 17.80%
1926 4.30% 14.10%
1927 21.90% 0.00%
1928 0.00% 27.00%
1929 3.90% 11.60%
1930 0.00% 16.30%
1931 0.00% 46.60%
1932 3.90% 5.90%
1933 0.00% 32.00%
1934 0.00% 48.80%
1935 0.00% 4.00%
1936 2.20% 20.40%
1937 5.90% 11.80%
1938 2.00% 2.00%
1939 0.00% 24.20%
1940 4.00% 2.10%
1941 26.60% 0.00%
1942 20.50% 0.00%
1943 0.00% 8.10%
1944 24.20% 1.90%
1945 22.20% 3.90%
1946 2.00% 7.90%
1947 22.80% 2.10%
1948 2.10% 4.10%
1949 4.20% 3.90%
1950 15.40% 6.20%
1951 28.40% 2.00%
1952 0.00% 31.30%
1953 7.50% 5.90%
1954 1.80% 16.20%
1955 5.50% 10.20%
1956 1.90% 14.70%
1957 22.00% 0.00%
1958 4.10% 6.00%
1959 4.00% 2.10%
1960 0.00% 11.80%
1961 4.00% 19.70%
1962 8.10% 0.00%
1963 4.00% 0.00%
1964 3.80% 6.20%
1965 38.10% 0.00%
1966 0.00% 13.80%
1967 11.80% 3.90%
1968 17.50% 0.00%
1969 12.20% 0.00%
1970 9.70% 7.90%
1971 16.50% 0.00%
1972 16.00% 1.90%
1973 8.70% 13.80%
1974 1.90% 8.20%
1975 8.40% 2.10%
1976 0.00% 30.20%
1977 11.80% 0.00%
1978 12.10% 1.90%
1979 2.10% 12.50%
1980 2.00% 8.40%
1981 0.00% 0.00%
1982 30.50% 0.00%
1983 14.70% 3.90%
1984 19.70% 2.00%
1985 14.90% 2.10%
1986 22.90% 0.00%
1987 2.00% 19.60%
1988 0.00% 28.30%
1989 7.80% 8.40%
1990 5.70% 15.40%
1991 4.10% 4.20%
1992 6.30% 8.00%
1993 44.50% 1.90%
1994 3.90% 8.00%
1995 17.70% 1.90%
1996 34.90% 1.90%
1997 6.10% 2.10%
1998 29.60% 0.00%
1999 8.10% 2.00%
2000 8.20% 4.00%
2001 0.00% 12.30%
2002 0.00% 14.40%
2003 4.00% 4.10%
2004 13.20% 2.00%
2005 5.80% 1.90%
2006 2.00% 12.60%
2007 8.10% 6.00%
2008 25.80% 0.00%
2009 34.00% 0.00%
2010 37.00% 4.70%
2011 24.60% 0.00%
2012 7.40% 30.20%
2013 26.20% 2.60%

*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.