Keywords: Average Drought Conditions in the Contiguous 48 States, 1895-2011.png en This graph shows average drought conditions in the contiguous 48 states according to the EPA with yearly data going from 1895 to 2011 As stated by the agency a value between -2 and -3 indicates moderate drought -3 to -4 is severe drought and -4 or below indicates extreme drought The curve is a nine-year weighted average 2013-05-15 03 59 39 This image was posted by the U S Environmental Protection Agency http //www epa gov/climatechange/images/indicator_figures/drought-figure1-2012 gif here U S Environmental Protection Agency PD-USGov Uploaded with UploadWizard Climate change in the United States Drought in the United States Global warming graphs |