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.

Year Percent
1910 8.20%
1911 4.30%
1912 9.70%
1913 18.90%
1914 0.00%
1915 11.90%
1916 4.00%
1917 10.00%
1918 9.90%
1919 12.00%
1920 2.30%
1921 6.00%
1922 7.90%
1923 8.30%
1924 0.00%
1925 2.10%
1926 4.20%
1927 2.00%
1928 6.50%
1929 16.20%
1930 4.10%
1931 4.10%
1932 7.90%
1933 9.70%
1934 7.70%
1935 2.00%
1936 23.10%
1937 6.20%
1938 9.80%
1939 0.00%
1940 3.80%
1941 13.80%
1942 17.20%
1943 9.50%
1944 18.00%
1945 7.70%
1946 2.00%
1947 4.00%
1948 6.10%
1949 0.00%
1950 5.70%
1951 9.80%
1952 11.50%
1953 6.10%
1954 0.00%
1955 7.50%
1956 9.50%
1957 3.80%
1958 5.60%
1959 2.00%
1960 13.70%
1961 15.60%
1962 3.80%
1963 11.40%
1964 37.60%
1965 0.00%
1966 5.60%
1967 5.80%
1968 0.00%
1969 24.10%
1970 8.00%
1971 16.20%
1972 3.80%
1973 16.90%
1974 4.10%
1975 7.70%
1976 10.10%
1977 13.10%
1978 14.30%
1979 19.70%
1980 22.00%
1981 6.00%
1982 4.10%
1983 15.10%
1984 17.10%
1985 3.70%
1986 13.50%
1987 11.30%
1988 5.90%
1989 5.80%
1990 10.10%
1991 7.60%
1992 5.90%
1993 15.30%
1994 21.20%
1995 7.90%
1996 13.60%
1997 3.90%
1998 26.40%
1999 2.00%
2000 9.30%
2001 15.90%
2002 9.50%
2003 20.20%
2004 8.10%
2005 10.60%
2006 8.30%
2007 25.40%
2008 4.00%
2009 10.80%
2010 11.00%
2011 9.00%
2012 10.20%
2013 16.40%

*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.