The portion of the country with some level of drought increased only slightly in the last week, but areas at risk for major crop losses and widespread water shortages jumped significantly, according to a report from the National Drought Mitigation Center.
Areas of the contiguous United States under extreme or exceptional drought conditions increased by an area roughly the size of Texas - from 13.5% of the land to 20.5% - in the past seven days, according to the Drought Monitor report released Thursday.
"It's getting to the point where some of the (agricultural) damage is not reversible" in the extreme-drought areas, said Brian Fuchs, a climatologist at the center. "The damage is done, and even with rain, you're not going to reverse some of these problems, at least not this growing season."
The areas newly put into the extreme category are spread over many states, including parts of Iowa, Illinois, Missouri, Nebraska, Oklahoma, Kansas, Arkansas and South Dakota. (See last week's map, for comparison with the one above.)
Meanwhile, the portion of the Lower 48 states under moderate or worse drought conditions rose slightly in the last week - from 63.54% to 63.86% - putting the contiguous United States in the largest drought by area in the report's 12-year history. This is the fourth consecutive week the Lower 48 set a Drought Monitor record in this category.
A week of very hot and very dry conditions - coming after roughly two months of similar weather - pushed more areas into the extreme or exceptional categories, Fuchs said.
Areas in the "extreme" drought category - the third most severe of four classifications - could see major crop and pasture losses with widespread water shortages, according to the center.
The lower two drought classifications are called moderate (some damage to crops and pastures possible, with some water shortages developing or imminent) and severe (crop or pasture losses likely, with water shortages common).
The highest classification, exceptional, means the area is at risk for widespread crop and pasture losses, with water emergencies.
Unrelenting heat and little to no rainfall across the nation’s heartland are making conditions difficult to overcome. Every state in the country, plus Puerto Rico, has at least a small area shown as abnormally dry or worse, Fuchs said.
Many of the areas that saw the drought intensify in the past week make up the country's corn and soybean belt - disheartening news for those that have already been tremendously affected.
Almost 90% of U.S. corn is grown in an area experiencing drought, and even recent and forecast rainfall will be too late to significantly help this year’s crop. Agriculture Department Secretary Tom Vilsack this week designated 76 additional counties in six states as drought disaster areas, bringing the total for the 2012 crop year to 1,369 counties across 31 states.
He also announced Monday that his department will cut the interest rates on emergency loans for farmers hard-hit by the drought to 2.25% from 3.75%.
On Thursday, Iowa's governor declared a disaster emergency to help farmers deal with the drought.
"The assistance comes in the form of a suspension of state laws and regulations affecting the transport of hay, straw and stover," a release from Gov. Terry Branstad said. "The drought has destroyed or depleted sources of these products that are necessary for livestock production and feed."
It’s not just crops that are suffering from the heat and lack of rainfall. A July 22 report from the Department of Agriculture said that 55% of the country’s pasture and range land was in poor to very poor condition. This is the highest percentage ever noted and is likely to profoundly hurt the nation’s cattle and dairy farmers.
Reports like this could continue, because U.S. forecasts don't offer any reprieve over the next several weeks. A persistent ridge of high pressure over portions of the country has sent the mercury to record levels over recent weeks and months. St. Louis has now seen a record 11 days with high temperatures reaching or exceeding 105 degrees this year, breaking the previous record of 10 days set in 1934, another year of historic heat and drought across the U.S.
Heat records like this will likely continue to fall. Above-normal temperatures are expected to continue through the beginning of August for much of the country, including the Great Plains.
The 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.
More on the drought:
Feds offer help to drought-stricken farmers
Farmer in the drought – if you plant it, it might not come
Farmer: 'If you eat, this drought will affect you'
Praying for rain in the Arkansas drought
From the field – tweets from #drought12
How the drought could hit your wallet
Opinion: Why the drought affects me - and you
Hogs feel drought's pinch
Drought forces farmers to sell cattle