NOAA

The drought ruining crops, shrinking water supplies and exacerbating wildfires intensified dramatically over the last week, U.S. forecasters reported Thursday.

The weekly Drought Monitor shows "widespread intensification" in the central U.S., the National Drought Mitigation Center said in a statement.

Across the contiguous U.S., the total area under all kinds of drought grew only slightly but the most severe categories -- extreme and exceptional -- rose from 13.5 percent to 20.5 percent -- the highest level since 2003.

The jump "this week was the largest since we started the U.S. Drought Monitor" 12 years ago, Brian Fuchs, a climatologist and Drought Monitor author, told NBC News. "This is really showing the rapid intensification of the drought due to the heat/dryness over the region with little relief for anyone."

"We’ve seen tremendous intensification of drought through Illinois, Iowa, Missouri, Indiana, Arkansas, Kansas and Nebraska, and into part of Wyoming and South Dakota in the last week," Fuchs said in the center's statement.

A drought is now gripping more than half of the nation, with the latest U.S. Drought Monitor showing some of the worst areas are expanding. In Tennessee, crops are dying and families are struggling to face the losses. NBC's Thanh Truong reports.

Every state had at least a small area categorized as "abnormally dry" or worse. "It’s such a broad footprint," Fuchs said.

The Weather Channel noted the jump is the equivalent of adding 219,000 square miles to the worst drought categories -- "an area slightly larger than the states of California and New York combined," it noted.

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States posting dramatic increases in just the last week included Illinois, which went from 8 percent in extreme/exceptional drought to 70 percent, and Nebraska, which went from 5 percent to 64 percent.

In Illinois, the drought is impacting water supplies in towns like Pontiac. "The Vermillion River does not have enough flow for us to use it as our primary source of water," one field observer reported Wednesday to the Drought Mitigation Center. "We have had to switch to a secondary source of water, located in a reservoir a few miles outside of town ... A 'dirt' like smell and taste is being noted ... We NEED rain, very soon."

The intensification also means drier soils and deteriorated pastures.

America's ongoing drought disaster is getting worse before it gets better. NBC's Chris Clackum reports.

"Over 90 percent of the topsoil was short or very short of moisture in Oklahoma, Kansas, Nebraska, Missouri, Iowa, Illinois, Indiana, and Ohio, with virtually all (99 percent) short or very short in Missouri and Illinois," the monitor stated. "Over 80 percent of the pasture and rangeland was in poor or very poor condition in Kansas, Arkansas, Missouri, Illinois, and Indiana."

A longer drought index compiled by the U.S. shows this year's drought now covers the most acreage since a dry spell in 1954. Two Dust Bowl years, 1934 and 1939, also had larger drought areas in the Palmer Drought Severity Index, which dates back to 1895 but is not as detailed as the Drought Monitor.

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