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% 33.60%
1911 0.00% 17.40%
1912 24.90% 9.60%
1913 2.20% 14.80%
1914 0.00% 52.00%
1915 0.00% 33.20%
1916 0.00% 42.90%
1917 0.00% 12.50%
1918 4.00% 18.00%
1919 6.30% 6.10%
1920 15.50% 2.10%
1921 6.00% 24.50%
1922 23.90% 0.00%
1923 31.90% 4.00%
1924 6.10% 0.00%
1925 0.00% 59.90%
1926 2.20% 26.20%
1927 1.90% 20.70%
1928 25.00% 0.00%
1929 24.20% 0.00%
1930 6.40% 7.80%
1931 4.20% 2.10%
1932 0.00% 3.70%
1933 3.80% 5.70%
1934 15.70% 0.00%
1935 15.80% 2.00%
1936 2.00% 9.70%
1937 4.20% 3.90%
1938 7.70% 6.10%
1939 9.60% 1.80%
1940 1.80% 5.80%
1941 0.00% 48.50%
1942 0.00% 13.20%
1943 0.00% 5.60%
1944 22.80% 4.00%
1945 1.90% 23.30%
1946 19.40% 1.90%
1947 12.40% 5.80%
1948 14.10% 0.00%
1949 5.80% 0.00%
1950 5.70% 0.00%
1951 5.50% 7.60%
1952 2.00% 1.90%
1953 6.10% 4.10%
1954 0.00% 1.80%
1955 0.00% 0.00%
1956 0.00% 7.80%
1957 29.60% 3.70%
1958 39.70% 0.00%
1959 29.50% 0.00%
1960 2.00% 11.80%
1961 7.70% 2.00%
1962 0.00% 3.80%
1963 0.00% 7.50%
1964 1.90% 0.00%
1965 11.70% 2.00%
1966 7.70% 1.80%
1967 1.80% 29.10%
1968 1.80% 0.00%
1969 2.10% 9.60%
1970 3.90% 0.00%
1971 2.00% 1.90%
1972 19.10% 1.90%
1973 47.50% 0.00%
1974 2.10% 0.00%
1975 36.30% 0.00%
1976 12.50% 5.70%
1977 0.00% 7.60%
1978 4.00% 0.00%
1979 11.60% 0.00%
1980 40.50% 0.00%
1981 0.00% 16.20%
1982 8.20% 0.00%
1983 13.00% 0.00%
1984 18.80% 0.00%
1985 0.00% 18.90%
1986 0.00% 53.70%
1987 6.00% 7.60%
1988 1.90% 5.80%
1989 19.30% 0.00%
1990 7.80% 8.20%
1991 58.40% 1.90%
1992 7.70% 10.00%
1993 3.90% 1.90%
1994 0.00% 7.80%
1995 0.00% 9.50%
1996 3.80% 3.90%
1997 3.80% 5.80%
1998 14.70% 5.80%
1999 0.00% 4.00%
2000 1.80% 21.20%
2001 3.90% 0.00%
2002 1.80% 2.00%
2003 58.50% 0.00%
2004 1.90% 26.50%
2005 8.40% 0.00%
2006 0.00% 24.60%
2007 0.00% 61.50%
2008 1.90% 4.00%
2009 30.90% 0.00%
2010 4.50% 2.20%
2011 6.50% 11.80%
2012 5.00% 5.10%
2013 3.50% 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.