DES MOINES, Iowa (AP) - The latest U.S. Drought Monitor map shows conditions have grown slightly worse in Iowa and Nebraska, where much of the nation's corn is grown.

The map shows the northwest corner of Iowa is now enduring an extreme drought, as are the east-central portion of the state and a section of southeast Iowa.

In a few parts of western Nebraska, the severe drought has worsened to extreme drought, with the eastern quarter remaining in severe drought. A few counties in central Nebraska continued to be listed as being under exceptional drought conditions.

The drought map is a project shared by the University of Nebraska-Lincoln, the U.S. Department of Agriculture and the National Weather Service. The latest map is based on conditions as of 6 a.m. Tuesday.

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