Chapter 4 - Drought and moisture surplus patterns in the conterminous United States: 2017, 2015-2017, and 2013-2017This article is part of a larger document. View the larger document here.
Although droughts affect most U.S. forests, there is considerable variation between regions in terms of drought frequency and intensity (Hanson and Weltzin 2000). These differences characterize the regions’ prevailing drought regimes. Most forests in the Western United States are subject to annual seasonal droughts. In contrast, forests in the Eastern United States usually experience one of two general drought patterns: random (i.e., occurring at any time of year) occasional droughts, as observed in the Appalachian Mountains and the Northeast, or frequent late-summer droughts, as usually observed in the Southeastern Coastal Plain and the eastern portion of the Great Plains (Hanson and Weltzin 2000).