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 6.60%
1911 2.60%
1912 5.20%
1913 0.00%
1914 2.20%
1915 11.20%
1916 21.80%
1917 2.30%
1918 10.50%
1919 12.00%
1920 9.30%
1921 4.50%
1922 9.60%
1923 0.00%
1924 2.30%
1925 9.20%
1926 11.70%
1927 7.30%
1928 11.50%
1929 0.00%
1930 4.40%
1931 11.30%
1932 0.00%
1933 10.90%
1934 6.70%
1935 2.40%
1936 19.70%
1937 0.00%
1938 8.40%
1939 15.90%
1940 21.90%
1941 4.40%
1942 6.60%
1943 9.00%
1944 2.30%
1945 13.50%
1946 9.60%
1947 8.90%
1948 6.90%
1949 13.20%
1950 8.70%
1951 6.50%
1952 8.80%
1953 10.70%
1954 14.90%
1955 17.20%
1956 6.70%
1957 15.40%
1958 2.20%
1959 21.90%
1960 10.80%
1961 13.10%
1962 6.70%
1963 4.30%
1964 15.40%
1965 13.30%
1966 13.00%
1967 12.60%
1968 8.90%
1969 6.30%
1970 10.70%
1971 9.00%
1972 24.30%
1973 2.30%
1974 8.60%
1975 8.70%
1976 6.70%
1977 4.30%
1978 11.30%
1979 4.20%
1980 19.40%
1981 17.30%
1982 11.00%
1983 17.30%
1984 10.60%
1985 12.80%
1986 10.50%
1987 6.50%
1988 12.80%
1989 11.20%
1990 8.60%
1991 15.40%
1992 8.90%
1993 10.70%
1994 8.70%
1995 24.80%
1996 10.70%
1997 11.10%
1998 11.10%
1999 15.10%
2000 4.60%
2001 10.70%
2002 6.30%
2003 8.90%
2004 9.20%
2005 17.40%
2006 20.20%
2007 5.10%
2008 20.30%
2009 0.00%
2010 11.20%
2011 18.70%
2012 8.30%
2013 11.00%
2014 10.80%

*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.