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 8.10%
1911 3.80%
1912 6.80%
1913 1.80%
1914 11.70%
1915 15.30%
1916 17.90%
1917 7.40%
1918 8.50%
1919 11.10%
1920 3.40%
1921 11.60%
1922 11.80%
1923 15.80%
1924 4.60%
1925 11.20%
1926 11.00%
1927 1.70%
1928 1.50%
1929 4.70%
1930 15.60%
1931 10.80%
1932 12.20%
1933 13.60%
1934 7.60%
1935 6.40%
1936 6.20%
1937 14.00%
1938 4.50%
1939 6.30%
1940 8.20%
1941 9.50%
1942 7.50%
1943 6.30%
1944 21.40%
1945 1.40%
1946 4.50%
1947 14.50%
1948 8.00%
1949 1.50%
1950 9.40%
1951 7.70%
1952 7.80%
1953 15.50%
1954 0.00%
1955 0.00%
1956 13.80%
1957 4.60%
1958 10.80%
1959 7.90%
1960 8.00%
1961 3.10%
1962 7.80%
1963 7.70%
1964 14.20%
1965 6.00%
1966 7.50%
1967 13.80%
1968 6.20%
1969 19.80%
1970 25.40%
1971 6.20%
1972 3.30%
1973 7.80%
1974 6.10%
1975 6.40%
1976 7.70%
1977 4.80%
1978 9.30%
1979 9.70%
1980 0.00%
1981 6.40%
1982 12.30%
1983 5.00%
1984 3.40%
1985 8.00%
1986 6.30%
1987 12.20%
1988 9.60%
1989 12.60%
1990 4.50%
1991 14.00%
1992 9.40%
1993 15.50%
1994 14.00%
1995 7.40%
1996 9.20%
1997 3.20%
1998 6.40%
1999 15.50%
2000 8.00%
2001 18.50%
2002 9.20%
2003 3.50%
2004 4.60%
2005 21.80%
2006 11.60%
2007 27.30%
2008 19.80%
2009 7.00%
2010 10.60%
2011 8.50%
2012 9.80%
2013 12.70%
2014 17.30%

*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.