1-year (2013), 3-year (2011-2013), and 5-year (2009-2013) drought maps for the conterminous United StatesThis article is part of a larger document. View the larger document here.
Doughts occur regularly in most U.S. forests, but their frequency and intensity vary widely between, as well as within, forest ecosystems (Hanson and Weltzin 2000). In the Western United States, forests commonly experience annual seasonal droughts. In the Eastern United States, forests tend to exhibit one of two prevailing drought patterns: random (i.e., occurring at any time of year), occasional droughts, as typically seen in the Appalachian Mountains and the Northeast; or frequent late-summer droughts, as typically seen in the southeastern Coastal Plain and the eastern edge of the Great Plains (Hanson and Weltzin 2000).