Crop prices closed sharply higher Tuesday as investors and grain consumers bought futures contracts ahead of a government report that often causes big swings in the market.

December wheat soared 49.25 cents, or 8 percent, to finish at $6.60 per bushel, December corn jumped 40 cents, or 6.6 percent, to end at $6.45 per bushel and November soybeans rose 58 cents, 4.9 percent, to $12.355 per bushel.

The U.S. Department of Agriculture will report its monthly prediction of global crop supplies Wednesday morning. Most analysts expect the report will show a bigger corn surplus and drive crop prices lower.

Despite those projections, there was a rush late Tuesday to buy contracts to avoid the uncertainty of what will happen Wednesday.

"Every report is a seriously, seriously high risk day, and tomorrow is going to be no different," said Jason Ward, an analyst with Northstar Commodity in Minneapolis. "Nobody is willing to take any risk going into these reports."

In other trading, copper for December delivery lost 7.75 cents, or 2.3 percent, to end at $3.2905 a pound. January platinum fell $6.30, or 0.4 percent, to finish at $1,518.80 an ounce. December palladium lost $10, or 1.6 percent, to $604.30 an ounce.

Precious metals were mixed. Gold for December delivery fell $9.80, or 0.6 percent, to $1,661 an ounce. December silver gained 1.8 cents, or 0.06 percent, to close at $31.998.

Oil prices rose. Benchmark oil gained 40 cents to end at $85.81 per barrel on the New York Mercantile Exchange.

Heating oil rose 0.02 cents to finish at $2.9041 per gallon, gasoline futures rose 5.23 cents to $2.7476 per gallon and natural gas rose 7.5 cents to $3.616 per 1,000 cubic feet.