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.

Download: Wet Data | Dry Data
Year Wet Dry
1910 0.00% 62.70%
1911 0.00% 15.10%
1912 2.30% 8.90%
1913 6.40% 6.50%
1914 0.00% 14.30%
1915 2.20% 16.60%
1916 9.30% 0.00%
1917 0.00% 25.20%
1918 0.00% 4.10%
1919 0.00% 2.20%
1920 2.20% 17.00%
1921 2.20% 6.60%
1922 2.10% 6.10%
1923 0.00% 24.10%
1924 4.50% 4.60%
1925 0.00% 46.60%
1926 0.00% 46.60%
1927 32.90% 0.00%
1928 0.00% 38.30%
1929 0.00% 10.70%
1930 0.00% 11.30%
1931 0.00% 30.30%
1932 0.00% 12.20%
1933 4.30% 10.60%
1934 0.00% 67.00%
1935 2.10% 6.30%
1936 5.90% 17.20%
1937 12.50% 8.10%
1938 24.70% 4.20%
1939 0.00% 43.50%
1940 4.10% 0.00%
1941 10.50% 6.70%
1942 9.20% 2.40%
1943 0.00% 4.80%
1944 33.70% 2.10%
1945 2.30% 6.60%
1946 6.90% 13.30%
1947 20.50% 0.00%
1948 0.00% 7.80%
1949 0.00% 20.70%
1950 12.20% 4.30%
1951 39.70% 0.00%
1952 0.00% 5.90%
1953 14.20% 2.10%
1954 1.90% 2.10%
1955 0.00% 16.20%
1956 12.00% 6.30%
1957 4.30% 4.20%
1958 0.00% 49.30%
1959 0.00% 8.20%
1960 14.40% 2.00%
1961 0.00% 1.90%
1962 5.90% 8.10%
1963 6.00% 6.30%
1964 0.00% 2.10%
1965 52.50% 0.00%
1966 4.00% 8.40%
1967 0.00% 14.50%
1968 9.90% 2.00%
1969 0.00% 7.70%
1970 11.90% 2.00%
1971 1.90% 18.60%
1972 4.00% 0.00%
1973 31.80% 0.00%
1974 21.50% 0.00%
1975 6.10% 0.00%
1976 4.10% 5.90%
1977 14.00% 0.00%
1978 0.00% 3.90%
1979 23.80% 0.00%
1980 0.00% 28.70%
1981 2.00% 12.30%
1982 29.30% 0.00%
1983 26.60% 0.00%
1984 19.00% 7.70%
1985 8.30% 0.00%
1986 6.10% 2.10%
1987 0.00% 6.10%
1988 0.00% 34.20%
1989 3.80% 14.20%
1990 12.50% 2.00%
1991 28.20% 0.00%
1992 2.20% 4.20%
1993 18.40% 1.90%
1994 0.00% 29.40%
1995 20.50% 0.00%
1996 0.00% 6.10%
1997 6.10% 4.20%
1998 17.20% 2.10%
1999 8.30% 0.00%
2000 10.50% 0.00%
2001 30.70% 0.00%
2002 24.40% 0.00%
2003 8.30% 0.00%
2004 41.80% 0.00%
2005 5.70% 2.10%
2006 14.10% 0.00%
2007 14.40% 0.00%
2008 2.10% 0.00%
2009 1.90% 4.10%
2010 2.30% 4.30%
2011 39.40% 0.00%
2012 26.50% 0.00%
2013 50.20% 0.00%

*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.