Aug. 2 (Bloomberg) -- The most extreme forms of drought spread last week in the lower 48 states, and moderate or worse conditions are expected to persist in the Midwest through October, according to U.S. monitors.
Extreme and exceptional drought, the two worst categories on a four-step scale, increased to 22.3 percent of the region in the week ended July 31, up from 20.6 percent, and expanded to 18.6 percent of the U.S. as a whole, up from 17.2 percent in the previous period, said the Drought Monitor in Lincoln, Nebraska.
The Midwest “continues to be impacted not only by oppressive heat, but also depleted soil moisture, desiccated pastures and widespread crop damages, livestock culling and elevated risk of fire,” Mark Svoboda of the National Drought Mitigation Center wrote in an assessment. “Recent concerns have now turned to soybeans and water supply as the drought’s duration persists.”
Drought, which hit hardest during a critical time for developing corn and soy plants, has pushed up prices for the crops as potential yields and quality have fallen. At least 48 percent of U.S. corn and 37 percent of soybeans were rated as poor or very poor as of July 29, according to the U.S. Agriculture Department.
The U.S. is the world’s largest corn grower and exporter. China said today it may reduce corn imports because of high prices.
In July, 0.79 of an inch of rain fell in Burlington, Iowa, 3.46 inches fewer than normal. In St. Louis, 0.72 of an inch fell, 3.39 inches below normal, according to the National Weather Service. Parts of the Southeast and the Dakotas saw rainfall improvement last week.
Across the U.S., 4,414 daily high temperature records were tied or set in July, the National Climatic Data Center in Asheville, North Carolina, reported.
Parched conditions are expected to spread through most of North Dakota and central Texas through October while persisting across the Midwest, according to the U.S. Seasonal Drought Outlook released today by the Climate Prediction Center in Camp Springs, Maryland.
There may be some improvement in southern Texas as well as in the eastern parts of Ohio and Michigan. The climate center forecasts improving conditions in the U.S. Southwest and in parts of Alabama, Georgia, South Carolina, New York, Virginia, Maryland, Delaware and Massachusetts.
Drought is also expected to spread across most of Hawaii. About half of the Big Island is already affected, along with about one-third of Oahu.
Some level of drought now covers 52.7 percent of the U.S., down from 53.4 percent last week, according to the Drought Monitor, a partnership between the Drought Mitigation Center at the University of Nebraska at Lincoln, the Agriculture Department and National Oceanic and Atmospheric Administration.
In the contiguous 48 states, moderate or worse conditions now affect 62.9 percent of the land, down from 63.9 percent last week, which was the highest level since the monitor was created in 2000.
It was also the most since 1956, in comparable terms, based on the Palmer Drought Index, according to a report written by David Miskus, senior meteorologist at the climate center.
In the short term, there is a 40 percent chance much of central U.S. won’t receive the normal amount of rain through the next month, according to the center.
The center’s maps show a large part of Nebraska, Iowa, Missouri, Kansas and Oklahoma may miss out on rain. Most neighboring states, including Illinois, Indiana, Arkansas and northern Texas, may get less rain than usual.
Drought is measured in four levels of severity from moderate to exceptional. In addition, forecasters note a fifth category, “abnormally dry,” which is often seen as precursor to drought.
Drought and abnormally dry conditions cover 71.2 percent of the U.S., down from 71.8 the previous week, according to the monitor. In the contiguous 48 states, 79.4 percent of the land is covered by the five levels, down from 80.1 percent.
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