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
1911 14.60%
1912 15.10%
1913 14.40%
1914 17.90%
1915 12.30%
1916 15.90%
1917 8.40%
1918 7.60%
1919 12.70%
1920 17.40%
1921 12.30%
1922 18.40%
1923 10.30%
1924 5.80%
1925 10.70%
1926 10.10%
1927 9.80%
1928 12.20%
1929 4.60%
1930 7.50%
1931 13.20%
1932 8.00%
1933 8.10%
1934 9.90%
1935 10.10%
1936 7.30%
1937 9.90%
1938 10.70%
1939 5.50%
1940 5.60%
1941 8.30%
1942 14.20%
1943 11.60%
1944 8.40%
1945 6.20%
1946 5.20%
1947 10.00%
1948 4.80%
1949 8.60%
1950 9.20%
1951 10.40%
1952 9.50%
1953 9.60%
1954 16.40%
1955 4.70%
1956 8.10%
1957 3.40%
1958 7.00%
1959 4.80%
1960 7.50%
1961 7.20%
1962 7.90%
1963 6.50%
1964 3.60%
1965 11.70%
1966 9.80%
1967 11.00%
1968 3.70%
1969 6.30%
1970 13.40%
1971 7.30%
1972 6.60%
1973 12.70%
1974 13.10%
1975 2.70%
1976 9.90%
1977 7.80%
1978 6.70%
1979 4.80%
1980 12.60%
1981 11.70%
1982 12.20%
1983 16.40%
1984 10.50%
1985 9.90%
1986 12.80%
1987 8.30%
1988 5.70%
1989 7.10%
1990 8.40%
1991 13.80%
1992 10.10%
1993 9.00%
1994 6.60%
1995 15.20%
1996 21.20%
1997 17.30%
1998 9.70%
1999 20.50%
2000 6.60%
2001 10.00%
2002 13.00%
2003 12.00%
2004 8.00%
2005 9.90%
2006 19.30%
2007 23.60%
2008 17.40%
2009 14.90%
2010 13.80%
2011 11.90%
2012 16.40%
2013 7.70%
2014 5.90%

*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.