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% 64.20%
1911 0.00% 27.00%
1912 21.00% 0.00%
1913 20.30% 0.00%
1914 0.00% 4.60%
1915 0.00% 17.70%
1916 9.60% 4.60%
1917 0.00% 43.50%
1918 4.70% 0.00%
1919 0.00% 62.10%
1920 0.00% 5.10%
1921 0.00% 4.80%
1922 0.00% 34.20%
1923 10.20% 4.80%
1924 0.00% 23.80%
1925 0.00% 14.10%
1926 0.00% 24.50%
1927 0.00% 4.70%
1928 0.00% 16.80%
1929 0.00% 0.00%
1930 0.00% 44.10%
1931 0.00% 4.90%
1932 8.90% 31.90%
1933 0.00% 0.00%
1934 0.00% 18.00%
1935 0.00% 4.70%
1936 0.00% 0.00%
1937 22.80% 0.00%
1938 0.00% 38.20%
1939 4.90% 0.00%
1940 0.00% 32.20%
1941 45.20% 0.00%
1942 0.00% 0.00%
1943 4.80% 0.00%
1944 5.20% 15.00%
1945 0.00% 18.30%
1946 18.80% 0.00%
1947 27.30% 0.00%
1948 35.00% 0.00%
1949 4.30% 31.80%
1950 0.00% 0.00%
1951 0.00% 30.20%
1952 0.00% 0.00%
1953 22.70% 0.00%
1954 58.40% 0.00%
1955 0.00% 4.80%
1956 9.00% 0.00%
1957 4.50% 9.80%
1958 10.00% 0.00%
1959 0.00% 0.00%
1960 0.00% 4.80%
1961 0.00% 0.00%
1962 4.30% 0.00%
1963 22.00% 0.00%
1964 41.30% 0.00%
1965 5.00% 0.00%
1966 4.30% 0.00%
1967 0.00% 61.20%
1968 28.50% 0.00%
1969 0.00% 8.90%
1970 0.00% 8.90%
1971 4.30% 0.00%
1972 4.50% 0.00%
1973 0.00% 14.00%
1974 0.00% 0.00%
1975 27.00% 0.00%
1976 54.60% 0.00%
1977 0.00% 0.00%
1978 50.10% 0.00%
1979 0.00% 0.00%
1980 36.20% 0.00%
1981 0.00% 0.00%
1982 19.10% 0.00%
1983 72.90% 0.00%
1984 4.70% 4.30%
1985 0.00% 4.80%
1986 0.00% 4.50%
1987 4.70% 4.70%
1988 0.00% 9.20%
1989 0.00% 0.00%
1990 36.90% 0.00%
1991 4.80% 0.00%
1992 4.90% 0.00%
1993 61.80% 0.00%
1994 0.00% 9.80%
1995 32.20% 0.00%
1996 0.00% 9.40%
1997 4.90% 0.00%
1998 0.00% 5.00%
1999 13.60% 0.00%
2000 0.00% 9.60%
2001 0.00% 0.00%
2002 0.00% 14.30%
2003 0.00% 33.80%
2004 4.70% 0.00%
2005 5.90% 0.00%
2006 0.00% 0.00%
2007 8.90% 8.90%
2008 9.40% 9.90%
2009 10.40% 9.90%
2010 5.20% 0.00%
2011 0.00% 0.00%
2012 11.80% 0.00%
2013 0.00% 0.00%
2014 11.40% 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.