High temperatures and little rain led to an unusually rapid widespread expansion of drought across the Upper Midwest on the August 27 U.S. Drought Monitor map.
The proportion of the contiguous United States in moderate drought or worse increased to 50.04 percent, a leap from 45.61 percent a week earlier. This is the first time since April 9 that drought has covered more than half of the continental United States.
“Above-normal temperatures and rapidly deteriorating soil moisture conditions have resulted in what appears to be a late-season flash drought,” said Anthony Artusa, this week’s U.S. Drought Monitor author, in narrative accompanying the map.
Moderate drought expanded across a large area of Minnesota and parts of the Dakotas and Wisconsin, and from Iowa and Missouri into Illinois. New areas of severe drought appeared in Iowa, Missouri and Nebraska and severe drought expanded in Arkansas and Louisiana, pushing into Mississippi, bringing the total area in severe drought to 33.37 percent of the continental United States, up slightly from 32.23 percent a week earlier.
“The portion of the U.S. corn production area in drought surged from 25 to 45 percent during the week ending August 27,” said Brad Rippey, a meteorologist in the U.S. Department of Agriculture’s Office of the Chief Economist. “Soybeans in drought also increased sharply in the last week, from 16 to 38 percent. Corn and soybeans in drought bottomed out last month at 17 and 8 percent, respectively. Meanwhile, hay (39 percent) and cattle in drought (52 percent) were both up six percentage points from a week ago.”
Temperatures in the Upper Midwest have been from 4 to 11 degrees above normal for the past week, Artusa said. He also cited records that point to an unusually dry summer. In southwest Iowa, Burlington had its wettest spring on record, with 19.23 inches of precipitation, which is 7.83 inches above normal, and is now on track to have its driest summer on record, with only 3.86 inches so far, 8.41 inches below normal. Other areas of the Midwest are on track for one of the driest Augusts on record.
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 map is released each Thursday based on data through the previous Tuesday morning.
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 USDA, and about 350 drought observers across the country. Artusa is with NOAA’s Climate Prediction Center.
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
Drought Impact Reporter: http://droughtreporter.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/
U.S. Monthly Drought Outlook:
http://www.cpc.ncep.noaa.gov/products/expert_assessment/monthly_drought.html
U.S. Seasonal Drought Outlook:
http://www.cpc.ncep.noaa.gov/products/expert_assessment/seasonal_drought.html
-- Kelly Helm Smith, National Drought Mitigation Center