The U.S. Drought Monitor showed drought shifting incrementally to the west on the map for the week that ended April 23, as drought-busting rains drenched the Midwest.
“Improbably, flooding has now replaced drought as the Midwest’s greatest imminent concern,” said Brad Rippey, U.S. Department of Agriculture meteorologist. “In fact, from April 20-23, the Mississippi River rose to one of its five highest levels on record from just south of Moline, Illinois, to just north of St. Louis, Missouri. … Farther west, rain and snow continued to chip away at long-term drought across the eastern Plains, but drought remained entrenched in most areas from California to the High Plains.”
This week’s U.S. Drought Monitor map shows the eastern edge of the lingering drought of 2012 receding westward, with the boundary of the drought forming a north-south line across Wisconsin, Minnesota, Iowa, Missouri, Arkansas, Oklahoma and Texas. Drought intensity eased in parts of South Dakota, Nebraska, and Oklahoma. Kansas and Texas saw drought recede in the east but intensify in the west.
Moderate drought expanded west to the Pacific Ocean in southern California, and drought expanded and intensified in northern California and parts of Oregon, Nevada, Arizona, New Mexico and Colorado. Drought also intensified in Florida.
Statistics released with the map showed fractional decreases in the area of the United States in moderate and severe drought and increases in the area in extreme and exceptional drought. The proportion of the contiguous 48 states in moderate drought or worse decreased to 47.34 percent from 47.82 percent last week; severe decreased to 31.75 percent from 32.10 percent; extreme increased to 14.72 percent from 14.57 percent; and exceptional increased to 2.59 percent from 2.58 percent.
U.S. Drought Monitor authors synthesize many drought indicators into a single map that identifies areas of the country that are abnormally dry (D0), in moderate drought (D1), in severe drought (D2), extreme drought (D3) and exceptional drought (D4).
The U.S. Drought Monitor map is jointly produced by the National Drought Mitigation Center at the University of Nebraska-Lincoln, the National Oceanic and Atmospheric Administration, the U.S. Department of Agriculture, and about 350 drought observers across the country. This week’s author was Eric Luebehusen, a meteorologist in the USDA’s Office of the Chief Economist.
The map is released each Thursday based on data through the previous Tuesday morning.
Statistics for the percent area in each category of drought are automatically added to the U.S. Drought Monitor website each week for the entire country and Puerto Rico, for the 48 contiguous states, for each climate region, and for individual states. U.S. Drought Monitor data online goes back to January 2000.
http://drought.unl.edu/MonitoringTools/USDroughtMonitor/DroughtMonitorTips.aspx
U.S. Drought Monitor map, statistics and narrative summary: http://droughtmonitor.unl.edu
USDA’s weekly “Agriculture in Drought” analysis: http://www.usda.gov/oce/weather/Drought/AgInDrought.pdf
National Climatic Data Center’s State of the Climate Drought Summary:
http://www.ncdc.noaa.gov/sotc/drought/
Seasonal Drought Outlook:
http://www.cpc.ncep.noaa.gov/products/expert_assessment/seasonal_drought.html
-- Kelly Helm Smith, National Drought Mitigation Center