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% 42.90%
1911 0.00% 0.00%
1912 0.00% 0.00%
1913 11.00% 0.00%
1914 0.00% 0.00%
1915 14.50% 0.00%
1916 13.20% 0.00%
1917 0.00% 28.80%
1918 0.00% 11.10%
1919 0.00% 0.00%
1920 0.00% 0.00%
1921 0.00% 0.00%
1922 24.70% 0.00%
1923 0.00% 62.20%
1924 0.00% 50.00%
1925 12.30% 0.00%
1926 0.00% 12.40%
1927 11.10% 10.50%
1928 0.00% 23.10%
1929 0.00% 62.80%
1930 0.00% 32.60%
1931 0.00% 10.50%
1932 0.00% 22.40%
1933 0.00% 25.10%
1934 0.00% 0.00%
1935 0.00% 0.00%
1936 0.00% 21.50%
1937 11.00% 0.00%
1938 22.00% 0.00%
1939 11.00% 44.80%
1940 22.00% 0.00%
1941 88.70% 0.00%
1942 0.00% 0.00%
1943 0.00% 10.50%
1944 0.00% 0.00%
1945 11.00% 0.00%
1946 0.00% 11.00%
1947 0.00% 43.90%
1948 22.30% 0.00%
1949 0.00% 0.00%
1950 11.30% 0.00%
1951 0.00% 0.00%
1952 33.70% 0.00%
1953 0.00% 22.70%
1954 0.00% 22.00%
1955 0.00% 11.00%
1956 0.00% 13.20%
1957 75.00% 0.00%
1958 10.50% 0.00%
1959 0.00% 89.50%
1960 0.00% 0.00%
1961 0.00% 11.70%
1962 0.00% 33.40%
1963 0.00% 0.00%
1964 0.00% 0.00%
1965 11.00% 0.00%
1966 0.00% 11.70%
1967 0.00% 0.00%
1968 0.00% 0.00%
1969 0.00% 0.00%
1970 11.00% 0.00%
1971 0.00% 0.00%
1972 0.00% 13.20%
1973 37.30% 0.00%
1974 0.00% 0.00%
1975 11.00% 0.00%
1976 0.00% 33.40%
1977 0.00% 0.00%
1978 11.70% 0.00%
1979 0.00% 0.00%
1980 0.00% 0.00%
1981 0.00% 0.00%
1982 23.10% 0.00%
1983 100.00% 0.00%
1984 0.00% 0.00%
1985 0.00% 0.00%
1986 0.00% 0.00%
1987 0.00% 0.00%
1988 0.00% 0.00%
1989 0.00% 11.40%
1990 0.00% 33.40%
1991 0.00% 11.00%
1992 0.00% 0.00%
1993 0.00% 0.00%
1994 0.00% 0.00%
1995 55.30% 0.00%
1996 44.40% 0.00%
1997 0.00% 11.40%
1998 89.00% 0.00%
1999 0.00% 0.00%
2000 0.00% 0.00%
2001 0.00% 0.00%
2002 0.00% 24.50%
2003 0.00% 0.00%
2004 0.00% 12.30%
2005 33.60% 0.00%
2006 67.40% 0.00%
2007 0.00% 44.20%
2008 0.00% 12.40%
2009 0.00% 0.00%
2010 85.90% 0.00%
2011 26.30% 0.00%
2012 13.50% 0.00%
2013 0.00% 34.30%

*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.