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% 59.70%
1911 0.00% 25.20%
1912 19.90% 0.00%
1913 19.30% 0.00%
1914 0.00% 4.40%
1915 0.00% 17.70%
1916 9.20% 4.40%
1917 0.00% 39.60%
1918 4.30% 0.00%
1919 0.00% 61.10%
1920 0.00% 4.80%
1921 0.00% 4.30%
1922 0.00% 31.10%
1923 14.00% 4.40%
1924 0.00% 22.70%
1925 0.00% 12.90%
1926 0.00% 22.20%
1927 0.00% 4.30%
1928 0.00% 15.00%
1929 0.00% 0.00%
1930 0.00% 44.60%
1931 0.00% 4.50%
1932 8.10% 29.20%
1933 0.00% 4.40%
1934 0.00% 20.60%
1935 0.00% 8.70%
1936 0.00% 0.00%
1937 20.80% 0.00%
1938 0.00% 34.80%
1939 4.50% 0.00%
1940 0.00% 29.50%
1941 41.00% 0.00%
1942 4.20% 0.00%
1943 4.30% 0.00%
1944 4.70% 13.60%
1945 0.00% 16.70%
1946 17.10% 0.00%
1947 26.10% 0.00%
1948 31.80% 0.00%
1949 3.90% 29.10%
1950 0.00% 0.00%
1951 0.00% 31.90%
1952 4.40% 0.00%
1953 20.70% 0.00%
1954 57.60% 0.00%
1955 0.00% 4.40%
1956 8.30% 0.00%
1957 4.30% 9.40%
1958 9.10% 0.00%
1959 0.00% 0.00%
1960 0.00% 4.40%
1961 0.00% 0.00%
1962 3.90% 0.00%
1963 28.70% 0.00%
1964 47.00% 0.00%
1965 9.10% 0.00%
1966 3.90% 0.00%
1967 0.00% 60.10%
1968 30.30% 0.00%
1969 0.00% 8.20%
1970 0.00% 12.30%
1971 3.90% 0.00%
1972 4.10% 0.00%
1973 0.00% 12.80%
1974 0.00% 4.60%
1975 24.70% 0.00%
1976 49.90% 0.00%
1977 0.00% 0.00%
1978 45.80% 0.00%
1979 0.00% 0.00%
1980 33.10% 0.00%
1981 0.00% 0.00%
1982 21.90% 0.00%
1983 75.20% 0.00%
1984 4.30% 3.90%
1985 0.00% 4.40%
1986 0.00% 4.10%
1987 4.50% 4.50%
1988 0.00% 8.40%
1989 0.00% 0.00%
1990 33.70% 0.00%
1991 4.40% 0.00%
1992 4.50% 0.00%
1993 65.20% 0.00%
1994 0.00% 8.90%
1995 34.00% 0.00%
1996 0.00% 13.10%
1997 4.50% 0.00%
1998 0.00% 4.50%
1999 12.40% 0.00%
2000 0.00% 13.30%
2001 0.00% 0.00%
2002 0.00% 17.30%
2003 0.00% 30.80%
2004 4.50% 0.00%
2005 5.50% 0.00%
2006 0.00% 0.00%
2007 8.10% 8.20%
2008 8.90% 9.40%
2009 9.40% 9.00%
2010 4.90% 0.00%
2011 0.00% 0.00%
2012 11.10% 0.00%
2013 0.00% 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.