CHICAGO (Dow Jones)--Corn futures on the Chicago Board of Trade declined for the fourth-straight session, reaching the lowest level in more than a week, as favorable U.S. Midwest crop conditions bolstered expectations for a near-record crop.

December corn fell 2 cents to $3.16 a bushel, the lowest closing price since $3.15 1/4. March futures fell 2 1/4 cents to $3.29.

"The market continues to give up weather premium," said Ray Jenkins, a grain merchandiser with Cargill Inc. in Eddyville, Iowa.

Corn and soybean crops in the Midwest will continue to benefit from near to above normal temperatures for at least the next 5-7 days, probably longer, according to DTN Meteorlogix.

The lack of "killing" frost in the near-term weather outlook suggests late-planted crops will gain additional time to fill out kernels and reach maturity.

"We are seeing the crop come to maturity a little faster than we expected," Jekins said. The chances of December corn breaking below $3 a bushel are "better than 50-50," he said.

November soybeans tumbled 27 1/2 cents to $9.13 1/2 a bushel.

Still, "we'll probably have to get into October and beyond the October crop report before the December contract is willing to break the $3 mark," he said.

A $3 futures price translates to about $2.50 in the cash, or spot, market, he said.

Corn futures have slumped from highs above $4.70 in June amid growing expectations for a bountiful harvest.

On Sept. 11, the U.S. Department of Agriculture raised its production estimate for the nation's corn crop to 12.954 billion bushels, which would be the second-largest on record next to a 13.038 billion-bushel harvest in 2007.

The most-recent forecast was up 2% from a previous estimate in August.

-By Bruce Blythe, contributing to Dow Jones Newswires; 312-750-4072