The pool is closed in Warrenton, Missouri. Cattle ponds are drying up in Arkansas. Illinois is in danger of losing its corn crop.

Even the mighty Mississippi River is feeling low amid what the National Climatic Data Center reported Monday is the largest drought since the 1950s.

The center said about 55% of the country was in at least moderate short-term drought in June for the first time since December 1956, when 58% of the country was in a moderate to extreme drought.

The hot, dry weather in June, which ranked as the third-driest month nationally in at least 118 years, according to the center, made the problem worse. The portion of the country suffering from severe to extreme short-term drought dramatically expanded in June, up to nearly 33% from 23% the month before.

Illinois Gov. Pat Quinn called it a “natural disaster of epic proportions.”

“We’ve never see a drought like this and we have to make sure we do something about it,” he said, calling on Congress to expedite passage of the farm bill. Quinn said seven more counties will be designated Monday as disaster areas, in addition to 26 already on the list, and farmers can apply for federal relief funds.

In Arkansas — where the Drought Mitigation Center reported that ranchers are having to haul water for cattle because ponds have dried out and wells can’t keep up with demands — 83-year-old retired farmer Don Hudson said this is about the worst he’s ever seen it.

“It’s very brown right now, ain’t no grass at all,” he said. “We’re still feeding hay because the cows aren’t even going out to graze.”

In all, 71% of the country was classified as abnormally dry or worse as of June, the climate agency said, citing data from the National Drought Mitigation Center at the University of Nebraska.

That’s double one year ago, according to agency statistics.

The worst-hit areas are the southern to central Rockies, the central Plains states and the Ohio Valley, the National Climatic Data Center said.

The hot, dry weather has taken its toll on agriculture, with 38% of the corn planted in the leading 18-corn producing states reported in poor or very poor conditions this week, according to the U.S. Department of Agriculture. The numbers are an increase of eight percentage points over last week and dramatically higher than last year at this time when it was just 11%.

In Arkansas, where conditions are the driest they’ve been since 1925, according to one widely used measure of short-term drought, ranchers have been selling off cattle to avoid having to feed and water them, said Arkansas Department of Agriculture spokesman Zach Taylor.

“It’s bad,” he said. “The week of July 4, we had 17,000 head of cattle sold. That may be a record.”

With parts of the country in an epic drought, water levels were also running low in the Mississippi River south of New Orleans, according to the U.S. Army Corps of Engineers. That was allowing saltwater to begin working its way upriver, which could threaten some water supplies.

It’s not unprecedented, and there’s no current threat to water supplies, but officials are prepared to start building an underwater barrier to block the denser saltwater from moving further upstream, Corps spokesman Ricky Boyett said Friday. The Corps last had to do that in 1999, he said.

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