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% 44.40%
1911 3.80% 8.90%
1912 3.60% 18.10%
1913 8.50% 2.50%
1914 3.60% 12.70%
1915 16.70% 14.50%
1916 0.00% 41.10%
1917 0.00% 49.40%
1918 0.00% 16.60%
1919 13.40% 1.10%
1920 0.00% 5.80%
1921 0.00% 31.20%
1922 3.80% 7.30%
1923 27.30% 1.30%
1924 0.00% 41.60%
1925 0.00% 25.80%
1926 3.50% 5.70%
1927 5.60% 10.70%
1928 2.20% 7.10%
1929 11.90% 4.80%
1930 4.90% 10.30%
1931 5.90% 5.90%
1932 9.10% 2.30%
1933 0.00% 20.70%
1934 1.20% 31.30%
1935 16.30% 11.50%
1936 2.40% 28.30%
1937 9.10% 2.20%
1938 0.00% 12.30%
1939 0.00% 13.20%
1940 7.70% 0.00%
1941 46.20% 1.20%
1942 9.80% 1.20%
1943 0.00% 29.30%
1944 13.60% 2.30%
1945 19.60% 5.90%
1946 6.30% 2.40%
1947 0.00% 3.20%
1948 5.80% 1.20%
1949 38.10% 0.00%
1950 10.50% 2.50%
1951 19.80% 4.80%
1952 0.00% 20.50%
1953 0.00% 10.10%
1954 0.00% 43.20%
1955 0.00% 13.40%
1956 0.00% 30.80%
1957 56.40% 0.00%
1958 23.90% 0.00%
1959 12.70% 2.30%
1960 14.00% 1.20%
1961 19.40% 0.00%
1962 4.50% 3.40%
1963 0.00% 24.00%
1964 0.00% 5.70%
1965 2.10% 2.30%
1966 2.30% 16.00%
1967 3.20% 2.30%
1968 28.90% 4.30%
1969 11.90% 3.40%
1970 2.30% 12.10%
1971 6.90% 1.20%
1972 7.80% 2.30%
1973 44.90% 0.00%
1974 13.50% 5.50%
1975 16.00% 1.10%
1976 8.20% 12.90%
1977 5.40% 4.60%
1978 2.30% 3.30%
1979 10.80% 1.10%
1980 0.00% 16.10%
1981 7.10% 3.50%
1982 15.10% 0.00%
1983 16.70% 1.10%
1984 12.30% 1.10%
1985 9.00% 1.20%
1986 17.60% 0.00%
1987 10.40% 0.00%
1988 0.00% 15.00%
1989 6.90% 2.30%
1990 12.50% 1.20%
1991 44.10% 0.00%
1992 43.90% 1.10%
1993 26.20% 0.00%
1994 10.80% 4.60%
1995 8.40% 3.60%
1996 3.40% 5.90%
1997 22.30% 0.00%
1998 3.30% 5.60%
1999 1.10% 24.40%
2000 1.10% 14.30%
2001 3.50% 5.60%
2002 3.60% 4.40%
2003 3.50% 11.30%
2004 34.90% 2.20%
2005 2.40% 16.80%
2006 0.00% 18.90%
2007 32.80% 9.60%
2008 4.80% 11.20%
2009 25.10% 2.60%
2010 1.10% 15.60%
2011 0.00% 32.00%
2012 1.30% 30.70%
2013 6.90% 2.80%

*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.