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 11.20%
1911 13.20%
1912 13.40%
1913 24.90%
1914 20.00%
1915 19.00%
1916 15.10%
1917 0.00%
1918 15.70%
1919 0.00%
1920 19.70%
1921 5.30%
1922 5.40%
1923 0.00%
1924 20.80%
1925 0.00%
1926 5.00%
1927 5.00%
1928 4.80%
1929 4.60%
1930 0.00%
1931 4.70%
1932 15.00%
1933 9.60%
1934 0.00%
1935 14.10%
1936 9.70%
1937 18.00%
1938 9.00%
1939 0.00%
1940 4.60%
1941 9.10%
1942 14.20%
1943 0.00%
1944 0.00%
1945 4.80%
1946 14.30%
1947 4.40%
1948 4.40%
1949 0.00%
1950 9.00%
1951 0.00%
1952 22.70%
1953 18.10%
1954 4.60%
1955 14.50%
1956 4.60%
1957 4.60%
1958 4.70%
1959 0.00%
1960 17.90%
1961 0.00%
1962 4.70%
1963 0.00%
1964 4.70%
1965 0.00%
1966 0.00%
1967 4.50%
1968 4.70%
1969 4.40%
1970 0.00%
1971 9.40%
1972 19.10%
1973 9.50%
1974 0.00%
1975 14.40%
1976 4.40%
1977 22.70%
1978 9.60%
1979 18.40%
1980 0.00%
1981 4.80%
1982 9.10%
1983 14.10%
1984 0.00%
1985 10.70%
1986 5.10%
1987 4.40%
1988 0.00%
1989 9.30%
1990 18.10%
1991 9.20%
1992 9.00%
1993 0.00%
1994 18.30%
1995 13.50%
1996 27.50%
1997 0.00%
1998 23.00%
1999 27.20%
2000 14.00%
2001 9.20%
2002 14.30%
2003 35.00%
2004 22.90%
2005 40.70%
2006 37.80%
2007 14.80%
2008 14.70%
2009 5.20%
2010 26.30%
2011 50.00%
2012 5.30%
2013 29.40%

*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.