Prices for corn, wheat and soybeans are settling higher again with no relief in sight from the drought blanketing farming states.

December corn rose 7.25 cents to $8.2375 a bushel Thursday. September wheat rose 13.75 cents to $9.13 a bushel and November soybeans rose 50 cents to $16.3125 a bushel.

A record-setting heat wave in July hit Plains states especially hard, new data show.

The weekly U.S. Drought Monitor map indicated that the amount of the contiguous U.S. affected by drought dropped a little more than 1 percentage point, to 78 percent. But the area still gripped by extreme or exceptional drought rose to 24 percent, up nearly 2 percentage points from the previous week.

Separately, a United Nations agency said an increase in the cost of grain and sugar helped to drive up global food prices in July.

The Food and Agriculture Organization's Food Price Index, which measures monthly change in the international prices of a group of food commodities, climbed 6 percent last month. The FAO is tasked with reducing world hunger at a time of near-record high food prices.

JPMorgan analysts said in a note to investors that the deterioration in the U.S. corn crop is "unlikely to be reversed." They also said hot and dry conditions throughout southeastern Europe, especially in Romania, Hungary, and Bulgaria, would also likely reduce global corn supplies.

On Friday the Department of Agriculture will releases updated predictions on production for corn, soybeans and other crops.

In other commodities trading, gold for December delivery rose $4.20 to $1,620.20 per ounce.

September silver rose 2.2 cents to $28.097 per ounce. October platinum rose $2.60 to $1,412.80 per ounce. September copper rose 0.35 cent to $3.425 per pound and September palladium rose 20 cents to $586.70 per ounce.

Energy commodities rose as well. Benchmark crude oil added 1 cent to finish at $93.36 per barrel in New York. Gasoline rose 2.04 cents to end at $3.0008 per gallon. Natural gas rose 1.2 cents to end at $2.945 per 1,000 cubic feet.