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 5.60% 20.80%
1911 8.40% 9.90%
1912 17.40% 1.90%
1913 0.00% 41.40%
1914 0.00% 14.20%
1915 70.90% 0.00%
1916 1.80% 9.00%
1917 12.80% 1.80%
1918 0.00% 17.10%
1919 0.00% 5.20%
1920 6.90% 8.60%
1921 1.70% 9.80%
1922 1.70% 18.00%
1923 3.30% 0.00%
1924 29.90% 1.80%
1925 1.80% 14.60%
1926 14.10% 0.00%
1927 6.70% 3.20%
1928 34.80% 0.00%
1929 0.00% 8.70%
1930 0.00% 34.90%
1931 1.70% 6.80%
1932 8.20% 6.60%
1933 0.00% 53.90%
1934 3.30% 12.90%
1935 16.40% 0.00%
1936 0.00% 64.70%
1937 6.60% 3.30%
1938 6.40% 3.30%
1939 9.90% 0.00%
1940 9.80% 5.00%
1941 10.00% 4.90%
1942 25.10% 1.60%
1943 9.60% 8.20%
1944 0.00% 11.60%
1945 6.90% 0.00%
1946 0.00% 6.70%
1947 5.10% 0.00%
1948 13.70% 0.00%
1949 23.80% 1.60%
1950 12.00% 4.90%
1951 16.50% 0.00%
1952 0.00% 11.50%
1953 0.00% 54.40%
1954 6.40% 6.70%
1955 0.00% 10.00%
1956 8.30% 1.60%
1957 1.70% 4.90%
1958 43.80% 0.00%
1959 0.00% 14.50%
1960 0.00% 1.60%
1961 14.90% 0.00%
1962 1.80% 6.70%
1963 0.00% 13.20%
1964 1.60% 9.90%
1965 4.90% 0.00%
1966 0.00% 11.60%
1967 6.60% 8.20%
1968 0.00% 12.30%
1969 4.90% 0.00%
1970 3.40% 3.30%
1971 0.00% 1.60%
1972 16.40% 1.70%
1973 1.70% 0.00%
1974 5.00% 3.30%
1975 11.70% 1.70%
1976 0.00% 18.90%
1977 19.90% 0.00%
1978 3.30% 4.90%
1979 35.20% 0.00%
1980 8.30% 14.00%
1981 34.50% 0.00%
1982 10.20% 0.00%
1983 0.00% 33.60%
1984 0.00% 22.00%
1985 25.00% 3.50%
1986 0.00% 1.80%
1987 13.20% 3.40%
1988 0.00% 51.30%
1989 12.10% 0.00%
1990 6.50% 6.90%
1991 0.00% 46.20%
1992 20.60% 1.80%
1993 32.90% 3.60%
1994 5.10% 3.50%
1995 1.70% 5.00%
1996 0.00% 3.60%
1997 3.70% 0.00%
1998 26.60% 1.70%
1999 0.00% 18.20%
2000 17.00% 0.00%
2001 13.40% 0.00%
2002 0.00% 18.20%
2003 24.30% 0.00%
2004 40.40% 0.00%
2005 5.40% 10.20%
2006 3.60% 1.90%
2007 0.00% 5.40%
2008 12.70% 3.60%
2009 12.60% 1.80%
2010 12.40% 3.70%
2011 0.00% 6.10%
2012 0.00% 29.20%
2013 25.00% 5.00%

*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.