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% 52.50%
1911 3.80% 24.70%
1912 25.00% 3.30%
1913 0.00% 44.50%
1914 3.30% 9.70%
1915 24.20% 0.00%
1916 0.00% 9.50%
1917 6.20% 0.00%
1918 0.00% 18.60%
1919 16.10% 2.90%
1920 15.10% 3.00%
1921 3.20% 6.00%
1922 3.00% 2.90%
1923 2.90% 2.80%
1924 9.90% 0.00%
1925 0.00% 14.40%
1926 60.80% 0.00%
1927 0.00% 16.50%
1928 12.40% 3.30%
1929 0.00% 8.60%
1930 0.00% 6.00%
1931 2.80% 0.00%
1932 0.00% 12.20%
1933 0.00% 21.90%
1934 0.00% 23.60%
1935 14.60% 0.00%
1936 0.00% 17.10%
1937 0.00% 2.80%
1938 17.90% 3.20%
1939 0.00% 6.00%
1940 0.00% 8.80%
1941 74.20% 0.00%
1942 0.00% 0.00%
1943 0.00% 3.20%
1944 17.20% 0.00%
1945 6.30% 0.00%
1946 8.60% 2.80%
1947 11.80% 6.30%
1948 0.00% 9.50%
1949 6.00% 0.00%
1950 0.00% 17.60%
1951 3.20% 0.00%
1952 27.90% 0.00%
1953 2.90% 0.00%
1954 0.00% 2.80%
1955 2.80% 24.40%
1956 0.00% 30.50%
1957 43.40% 0.00%
1958 49.50% 0.00%
1959 2.80% 24.00%
1960 0.00% 3.20%
1961 5.70% 0.00%
1962 0.00% 5.80%
1963 2.70% 11.50%
1964 8.70% 0.00%
1965 23.90% 0.00%
1966 0.00% 64.10%
1967 0.00% 6.00%
1968 9.30% 0.00%
1969 2.80% 8.50%
1970 0.00% 0.00%
1971 0.00% 18.90%
1972 0.00% 52.00%
1973 40.10% 0.00%
1974 0.00% 28.50%
1975 21.90% 0.00%
1976 0.00% 0.00%
1977 0.00% 3.00%
1978 22.70% 3.10%
1979 16.00% 3.10%
1980 19.20% 0.00%
1981 15.20% 0.00%
1982 7.50% 0.00%
1983 34.10% 0.00%
1984 0.00% 6.00%
1985 11.90% 0.00%
1986 5.90% 0.00%
1987 26.00% 0.00%
1988 0.00% 3.10%
1989 0.00% 27.70%
1990 8.80% 0.00%
1991 5.80% 3.10%
1992 54.60% 8.40%
1993 8.70% 0.00%
1994 6.20% 3.00%
1995 46.70% 0.00%
1996 2.90% 25.50%
1997 0.00% 0.00%
1998 5.80% 2.90%
1999 5.90% 0.00%
2000 0.00% 0.00%
2001 0.00% 0.00%
2002 0.00% 47.50%
2003 0.00% 3.30%
2004 3.20% 0.00%
2005 3.10% 0.00%
2006 0.00% 3.00%
2007 9.00% 5.70%
2008 0.00% 13.50%
2009 3.10% 3.30%
2010 3.30% 0.00%
2011 22.70% 5.00%
2012 0.00% 38.60%
2013 3.60% 15.10%
2014 5.40% 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.