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 16.70% 3.30%
1911 5.10% 15.10%
1912 2.70% 15.50%
1913 0.00% 21.70%
1914 0.00% 19.90%
1915 2.10% 9.00%
1916 17.20% 2.30%
1917 6.80% 6.80%
1918 0.00% 21.10%
1919 12.40% 0.00%
1920 11.10% 6.90%
1921 2.30% 16.20%
1922 12.10% 4.90%
1923 10.10% 12.20%
1924 7.20% 9.50%
1925 0.00% 39.10%
1926 11.60% 4.50%
1927 14.10% 0.00%
1928 29.20% 0.00%
1929 4.60% 9.50%
1930 0.00% 35.30%
1931 2.10% 16.70%
1932 16.00% 6.50%
1933 2.20% 4.30%
1934 6.60% 2.10%
1935 4.70% 0.00%
1936 0.00% 11.30%
1937 17.80% 2.30%
1938 4.10% 2.20%
1939 24.30% 0.00%
1940 6.70% 4.40%
1941 24.80% 0.00%
1942 6.50% 0.00%
1943 2.30% 17.70%
1944 2.30% 8.50%
1945 6.50% 2.10%
1946 2.50% 4.90%
1947 4.50% 4.40%
1948 4.60% 9.30%
1949 28.20% 0.00%
1950 16.80% 0.00%
1951 0.00% 15.40%
1952 4.20% 15.10%
1953 2.20% 21.30%
1954 0.00% 49.60%
1955 2.10% 4.60%
1956 0.00% 9.00%
1957 0.00% 10.60%
1958 10.90% 2.30%
1959 0.00% 6.60%
1960 4.30% 4.10%
1961 30.10% 4.60%
1962 11.70% 0.00%
1963 2.10% 10.40%
1964 11.10% 2.10%
1965 11.30% 0.00%
1966 2.30% 10.50%
1967 19.40% 2.10%
1968 2.30% 6.30%
1969 4.10% 0.00%
1970 6.50% 2.30%
1971 15.50% 0.00%
1972 0.00% 13.60%
1973 21.10% 6.90%
1974 9.00% 4.30%
1975 6.80% 2.10%
1976 0.00% 8.90%
1977 2.30% 8.50%
1978 2.40% 6.90%
1979 2.10% 6.60%
1980 0.00% 59.00%
1981 2.10% 4.30%
1982 11.20% 0.00%
1983 2.30% 47.20%
1984 2.10% 8.60%
1985 15.10% 2.20%
1986 8.90% 12.60%
1987 0.00% 15.30%
1988 0.00% 18.80%
1989 41.40% 2.20%
1990 2.30% 30.30%
1991 13.30% 0.00%
1992 15.40% 0.00%
1993 0.00% 33.80%
1994 47.90% 0.00%
1995 4.40% 2.30%
1996 4.10% 6.50%
1997 8.50% 8.40%
1998 4.20% 28.70%
1999 2.30% 14.80%
2000 6.50% 14.10%
2001 6.40% 0.00%
2002 4.50% 4.20%
2003 55.10% 0.00%
2004 24.20% 0.00%
2005 21.70% 0.00%
2006 0.00% 14.00%
2007 0.00% 7.20%
2008 2.30% 6.70%
2009 6.30% 6.50%
2010 2.20% 4.40%
2011 0.00% 14.20%
2012 5.60% 0.00%
2013 57.80% 2.90%
2014 19.20% 3.90%

*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.