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 5.70% 21.20%
1911 8.50% 10.10%
1912 17.80% 2.00%
1913 0.00% 40.40%
1914 0.00% 14.50%
1915 70.30% 0.00%
1916 1.80% 9.20%
1917 11.20% 1.80%
1918 0.00% 17.40%
1919 0.00% 5.30%
1920 7.00% 8.70%
1921 1.70% 10.00%
1922 1.70% 18.30%
1923 3.30% 0.00%
1924 28.70% 3.60%
1925 3.60% 16.80%
1926 12.70% 0.00%
1927 6.80% 3.30%
1928 33.70% 0.00%
1929 0.00% 8.70%
1930 0.00% 35.50%
1931 1.70% 7.00%
1932 8.30% 6.80%
1933 0.00% 51.50%
1934 3.40% 13.10%
1935 16.70% 0.00%
1936 0.00% 64.70%
1937 6.70% 3.30%
1938 6.50% 3.40%
1939 8.40% 0.00%
1940 10.00% 5.10%
1941 8.50% 5.00%
1942 23.90% 1.60%
1943 9.80% 8.30%
1944 0.00% 11.80%
1945 7.00% 0.00%
1946 0.00% 6.80%
1947 3.50% 0.00%
1948 13.90% 0.00%
1949 25.90% 1.70%
1950 14.00% 3.40%
1951 14.90% 0.00%
1952 0.00% 11.70%
1953 0.00% 53.60%
1954 6.50% 8.60%
1955 0.00% 6.80%
1956 10.10% 1.70%
1957 1.70% 5.00%
1958 44.60% 0.00%
1959 0.00% 14.80%
1960 0.00% 1.60%
1961 15.10% 0.00%
1962 1.80% 6.80%
1963 0.00% 11.70%
1964 1.70% 11.90%
1965 5.00% 0.00%
1966 0.00% 11.80%
1967 6.80% 8.30%
1968 0.00% 10.80%
1969 4.90% 0.00%
1970 3.40% 3.40%
1971 0.00% 1.70%
1972 16.70% 1.70%
1973 1.70% 0.00%
1974 5.10% 3.40%
1975 12.00% 1.80%
1976 0.00% 17.40%
1977 16.90% 0.00%
1978 3.40% 5.00%
1979 34.10% 0.00%
1980 8.40% 12.50%
1981 31.80% 0.00%
1982 10.40% 0.00%
1983 0.00% 32.50%
1984 0.00% 22.40%
1985 22.00% 3.50%
1986 0.00% 1.80%
1987 13.50% 3.40%
1988 0.00% 53.90%
1989 12.30% 0.00%
1990 6.60% 7.00%
1991 0.00% 47.00%
1992 22.70% 1.80%
1993 31.70% 3.60%
1994 5.20% 3.50%
1995 3.40% 5.10%
1996 0.00% 3.70%
1997 3.70% 0.00%
1998 24.90% 1.70%
1999 0.00% 18.50%
2000 13.80% 0.00%
2001 11.70% 0.00%
2002 0.00% 18.50%
2003 24.30% 0.00%
2004 40.40% 0.00%
2005 5.50% 10.40%
2006 3.60% 1.90%
2007 0.00% 3.70%
2008 11.10% 3.70%
2009 14.70% 1.80%
2010 14.20% 3.70%
2011 0.00% 6.10%
2012 0.00% 29.20%
2013 27.50% 11.70%
2014 18.90% 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.