National Drought Mitigation Center


U.S. Drought Monitor shows slight expansion of drought over Upper Midwest

September 20, 2012

The U.S. Drought Monitor map for the seven days ending Sept. 18 showed little change from the preceding week, although the total area of the country in moderate or worse drought crept up to yet another record high in the 12-year U.S. Drought Monitor data.

Statistics released with the map showed that 54.25 percent of the country was in moderate drought or worse, the largest percentage so far recorded at that level, up slightly from 53.70 percent the week before. The map showed 34.35 percent in severe drought or worse, down from 34.97 percent a week earlier; 17.35 percent in extreme drought or worse, compared with 17.63 percent the week before; and 4.98 percent in exceptional drought, compared with 5.20 percent the preceding week.

Moderate drought expanded in Minnesota, Wisconsin and the Dakotas. Although all of Kansas is still in severe drought or worse, the area in exceptional drought decreased to 51.04 percent from 60.61 percent. Oklahoma saw slight intensification, with the area in extreme drought increasing to 95.33 percent from 94.68 percent, and the area in exceptional drought increasing to 42.09 percent from 39.66 percent.

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. It is released each Thursday based on data through the previous Tuesday.

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:

The National Climatic Data Center maintains drought data based on the Palmer Drought Severity Index, calculated to the beginning of the historic record:

U.S. Drought Monitor:

Seasonal Drought Outlook:

U.S. Department of Agriculture’s running tally of farm and food impacts from the Drought of 2012: