News Section
Stories from Climate Central's Science Journalists and Content Partners

Spurred by Record Heat, Drought Stretches Across U.S.

Drought conditions have expanded and reached another record level for the 21st century as of Thursday, escalating concerns about the fate of the 2012 corn crop. As of Thursday morning, nearly 61 percent of the country was classified as being in at least moderate drought, up from about 56 percent just one week ago, which was the largest swath of the country to be affected by drought conditions since the Drought Monitor began in 2000.

According to the weather summary accompanying the new edition of the Drought Monitor, record heat from mid-June to early July overwhelmed any beneficial rainfall that fell during the past week, causing an expansion in the areas of most severe drought conditions.

U.S. Drought Monitor showing that drought conditions extended coast-to-coast as of July 10. Click on the image for a larger version. Credit: NOAA/USDA.

The drought assessment offers corn growers little reason for optimism. They have already seen the prospect of a banner year disappear due to the combination of record heat and abnormally dry conditions.

According to the Drought Monitor, in the 18 main corn-growing states, 30 percent of the corn crop is now listed as being in “poor” or “very poor” condition, an increase from 22 percent the previous week. “In addition, fully half of the nation’s pastures and ranges are in poor or very poor condition, up from 28 percent in mid-June,” the report stated.

According to Reuters, the U.S. Department of Agriculture has cut its estimate of the corn crop more severely than market analysts had anticipated, and corn and soybean prices have risen by more than a third during the past month. “The report initially re-ignited a near-record rally in grain prices that could eventually hit consumer grocery bills in North America, although the impact could be more immediate for the world's poor if the drought persists,” Reuters reported on Wednesday.

Climate studies have shown that precipitation extremes, including both heavy precipitation and drought, are becoming more common worldwide as global warming increases the amount of moisture in the air. However, attributing droughts at the country or regional level is difficult, since natural climate variability plays a large role in influencing weather patterns. One study released on Tuesday found that manmade global warming made the 2011 Texas heat and drought 20 times more likely to occur compared to the 1960s.

The heat wave that extended from mid-June through early July intensified drought conditions in the northern Plains and Mississippi Valley, according to the latest drought assessment.

The expanding drought has also created ideal conditions for wildfires, with 3.1 million acres burned so far this year, up from 1.1 million just three weeks ago.

Precipitation outlook for the next five days, made on Thursday, July 12. Credit: NOAA.

Areas that have seen the most significant drought expansion during the past week include the Tennessee Valley, along with the lower Ohio River and in northeastern Indiana, where rainfall has been running up to nearly a foot below average during the past three months. In addition, drought conditions have “deteriorated significantly” in much of Arkansas, Missouri, and Oklahoma, where drought experts introduced areas of “extreme drought” for the first time this year.

Drought conditions have improved in the southern High Plains and Rockies, as well as Louisiana, New Mexico, and eastern Texas.

Rainfall outlooks for the next five days show beneficial rains may largely miss the areas that are experiencing the most severe drought conditions, particularly in the middle Mississippi Valley and central and southern Plains.