By Christine Stebbins
Chicago (Reuters) - U.S. drought conditions expanded for the fourth week in a row as dryness persisted in the western half of the country, including key crop states of Kansas and Nebraska, while conditions in the South reached their driest in two months, according to a weekly drought report.
In contrast, the eastern half of the United States remained out of drought, given steady summer rains and cool temperatures.
The U.S. Drought Monitor, issued by state and federal experts, said on Thursday that drought areas in the "moderate to exceptional" range reached 44.85 percent, up from 44.06 percent a week ago.
"Dry conditions persisted across most of the southern Great Plains and Lower Mississippi River Valley," the online U.S. Drought Monitor said.
While temperatures there were still generally below normal for the week, they were still warm, it said. "Accordingly, the coverage of drought conditions was increased across the Southern Great Plains."
Drought Monitor author Matthew Rosencrans of the U.S. Climate Prediction Center told Reuters the biggest change was across Arkansas, Louisiana and eastern Oklahoma.
"They had been wet in May and had some drought recovery there, but I had to really expand conditions across Arkansas, Louisiana and southern Missouri," said Rosencrans, who does not expect much drought relief for next week.
The drought also intensified in Texas, the report said.
"Farther north and west, across Oklahoma and southeastern Colorado, reports indicate sage brush and large trees dying and even some cacti turning brown," the Drought Monitor said. "Some drought expansion was also introduced across Kansas, where topsoil moisture reports indicated an increase of 38 percentage points for the portion of reports indicating short or very short moisture amounts."
In Kansas, the top wheat producer, 75.73 percent of the state is rated moderate to exceptional drought, up from 74.56 percent a week ago. But that is much improved from a year ago, when nearly 98 percent was in moderate to exceptional drought.
Nebraska, the fourth-largest corn state and a big producer of cattle, sorghum, wheat and ethanol, is the driest of the big crop states, with 88.41 percent in moderate to exceptional drought. That is unchanged from last week but far worse than a year ago at 77.22 percent.
Link to monitor: http://droughtmonitor.unl.edu/
(Reporting by Jonathan Leff and Christine Stebbins; Editing by Nick Zieminski and Lisa Von Ahn)