National Drought Mitigation Center


Aug. 21 U.S. Drought Monitor shows small intensification in mid-section and improvement to the east

August 23, 2012

Drought intensified slightly over Nebraska, Missouri, Kansas and Iowa, and eased through Ohio, Indiana and the Mid-Atlantic during the seven days that ended Aug. 21, according to the U.S. Drought Monitor map released today.

“The total area in moderate or worse drought actually increased, but that’s not as bad as it sounds, because the areas in severe and extreme drought decreased,” said Mark Svoboda, a climatologist and U.S. Drought Monitor author at the National Drought Mitigation Center, based at the University of Nebraska-Lincoln. “That said, exceptional drought expanded ever so slightly in Missouri, Kansas and Nebraska, but reduced in and around central Indiana and Illinois after heavy rains. So all in all, this map shows a bit of a mixed bag at first glance, with the best improvements coming in the eastern Corn Belt and Mid-Atlantic.”

He added, “Long-term impacts and hydrological indicators are lagging behind in their recovery, as expected, so long-term issues are not totally resolved yet. The map shows continued shrinking of the drought in the Southeast as well, but the intense core remains intact for now.”

Statistics released with the map showed 52.89 percent of the country was in moderate drought or worse, up 1 percent from 51.70 percent the week before. The map showed 36.83 percent in severe drought or worse, compared with 38.09 percent a week earlier; 19.24 percent in extreme drought or worse, compared with 19.79 percent the week before; and 5.27 percent in exceptional drought, up from 5.23 percent the preceding week.

Recovery from the Drought of 2012 is likely to be slow. “We’ve reached the apex of our precipitation for the mid-section of the country – it’s pretty much downhill from here until next spring -- so rapid, large-scale improvements would be unexpected, although certainly not impossible,” Svoboda said. “Mother Nature has a way of tipping the scales back quite rapidly at times, too rapidly, in fact, but at this point we’ll take what we can get whenever we can get it.”

In the West, on a more favorable note, Svoboda noted that consistent monsoon rains across southern Arizona and New Mexico as well as southeastern California have led to some improvements on this week’s map. But further west, Hawaii has been in a long-term drought, with extreme drought introduced to the island of Lanai this week.

After two years of warmer, drier winters associated with the La Niña weather pattern, “The likely onset of El Niño this fall may signal a change in our atmospheric fortunes,” Svoboda said. “El Niño would be more likely to bring a cooler and wetter winter for the southern tier states, hopefully bringing relief and recovery to states now experiencing two consecutive years of drought,” such as Georgia, Alabama, Texas, Louisiana, Arkansas, Oklahoma and New Mexico.

“We also hope to see a much better snowpack year for much of the West, particularly the Rockies and the Wasatch, which will help rebuild water supply in these regions, especially after a lackluster wet season last year,” Svoboda added.

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:

-- Kelly Helm Smith, National Drought Mitigation Center