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% 25.20%
1911 1.20% 15.60%
1912 9.80% 0.00%
1913 0.00% 27.80%
1914 15.80% 9.50%
1915 13.10% 6.70%
1916 0.00% 33.00%
1917 0.00% 11.60%
1918 0.00% 23.00%
1919 3.20% 1.10%
1920 1.00% 12.20%
1921 0.00% 24.30%
1922 23.60% 0.00%
1923 16.00% 3.40%
1924 4.20% 3.20%
1925 0.00% 42.90%
1926 12.00% 3.00%
1927 9.20% 19.10%
1928 1.00% 12.40%
1929 15.20% 0.00%
1930 2.20% 1.00%
1931 5.50% 4.50%
1932 0.00% 13.40%
1933 2.00% 8.10%
1934 2.20% 13.90%
1935 6.10% 1.00%
1936 4.40% 16.30%
1937 0.00% 5.20%
1938 8.90% 2.10%
1939 0.00% 11.40%
1940 0.00% 5.00%
1941 43.50% 2.00%
1942 3.20% 2.20%
1943 5.00% 4.10%
1944 21.90% 0.00%
1945 12.80% 2.00%
1946 3.20% 5.20%
1947 33.30% 0.00%
1948 0.00% 4.30%
1949 16.10% 1.00%
1950 6.40% 7.10%
1951 3.90% 4.00%
1952 8.90% 2.10%
1953 6.90% 2.00%
1954 0.00% 7.20%
1955 1.00% 12.30%
1956 0.00% 24.40%
1957 79.80% 0.00%
1958 37.20% 0.00%
1959 2.10% 2.10%
1960 1.10% 12.60%
1961 11.20% 17.60%
1962 0.00% 20.20%
1963 0.00% 12.80%
1964 3.20% 5.10%
1965 10.70% 3.10%
1966 4.40% 26.80%
1967 1.00% 12.30%
1968 27.50% 2.90%
1969 8.30% 1.00%
1970 7.20% 0.00%
1971 0.00% 22.70%
1972 0.00% 12.20%
1973 47.30% 1.10%
1974 0.00% 18.70%
1975 27.60% 0.00%
1976 19.00% 0.00%
1977 8.90% 5.10%
1978 4.10% 7.50%
1979 25.10% 0.00%
1980 17.50% 1.00%
1981 9.40% 1.10%
1982 18.40% 0.00%
1983 18.50% 1.10%
1984 12.60% 10.10%
1985 3.20% 1.00%
1986 4.30% 3.00%
1987 10.60% 7.30%
1988 0.00% 7.20%
1989 0.00% 8.00%
1990 41.90% 0.00%
1991 29.70% 4.20%
1992 10.80% 2.00%
1993 27.70% 0.00%
1994 8.60% 7.10%
1995 41.20% 0.00%
1996 0.00% 36.20%
1997 22.60% 2.00%
1998 0.00% 22.40%
1999 6.20% 1.00%
2000 5.10% 4.30%
2001 2.10% 5.10%
2002 1.10% 16.10%
2003 1.10% 23.30%
2004 7.60% 4.10%
2005 3.20% 11.90%
2006 0.00% 15.10%
2007 28.90% 11.10%
2008 0.00% 4.50%
2009 5.60% 1.20%
2010 1.10% 4.40%
2011 0.00% 47.20%
2012 0.00% 16.40%
2013 1.60% 9.40%

*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.