Drought conditions spread slightly in the last week to cover more than 54 percent of the United States, a record high, experts said.

The latest U.S. Drought Monitor released this morning showed a half-percentage-point uptick in the drought's national footprint, setting a record in the monitor's 12-year history.

The map shows 34 percent of the nation in severe drought or worse, down 1 point from the week before. Seventeen percent is in extreme drought or worse, compared with 18 percent the week before. And slightly more than 5 percent is in exceptional drought, up from slightly less than 5 percent the week prior.

Moderate drought expanded in Minnesota, Wisconsin and the Dakotas. All of Kansas remains in severe drought or worse, although the area in exceptional drought decreased to 51 percent from 61 percent.

Oklahoma's drought intensified slightly, with the area suffering extreme conditions increasing less than a point to 95 percent and the area in exceptional conditions growing to 42 percent from 40 percent.