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 5.40%
1911 3.40%
1912 5.70%
1913 12.20%
1914 3.50%
1915 7.70%
1916 11.10%
1917 5.60%
1918 8.70%
1919 10.20%
1920 12.00%
1921 3.40%
1922 16.70%
1923 10.10%
1924 9.90%
1925 7.30%
1926 5.20%
1927 11.60%
1928 5.20%
1929 12.20%
1930 6.90%
1931 11.90%
1932 10.10%
1933 18.00%
1934 19.60%
1935 8.20%
1936 12.10%
1937 13.10%
1938 14.80%
1939 4.90%
1940 4.90%
1941 6.60%
1942 8.40%
1943 13.00%
1944 6.70%
1945 3.50%
1946 20.40%
1947 6.80%
1948 3.40%
1949 6.70%
1950 6.50%
1951 7.30%
1952 6.50%
1953 5.00%
1954 4.90%
1955 11.60%
1956 5.00%
1957 14.90%
1958 21.90%
1959 3.30%
1960 10.10%
1961 8.20%
1962 3.40%
1963 4.90%
1964 13.50%
1965 9.90%
1966 10.10%
1967 4.90%
1968 10.40%
1969 16.40%
1970 11.70%
1971 3.40%
1972 4.90%
1973 13.80%
1974 5.00%
1975 3.40%
1976 10.60%
1977 8.20%
1978 3.30%
1979 9.90%
1980 10.10%
1981 16.10%
1982 5.20%
1983 11.70%
1984 11.80%
1985 8.30%
1986 5.20%
1987 9.90%
1988 15.00%
1989 8.40%
1990 9.90%
1991 10.20%
1992 14.00%
1993 12.30%
1994 8.60%
1995 8.50%
1996 6.90%
1997 7.00%
1998 17.40%
1999 9.90%
2000 15.20%
2001 3.80%
2002 13.10%
2003 6.80%
2004 3.40%
2005 12.40%
2006 14.80%
2007 29.40%
2008 14.20%
2009 11.20%
2010 14.40%
2011 16.50%
2012 6.10%
2013 17.50%

*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.