* Corn firms after hitting lowest since August 2010
* Soy rises, expiring contract supported by commercial stoppers
* Wheat mixed: CBOT firm; KCBT, MGEX contracts weaken
* Market waiting for USDA report on Friday
CHICAGO, Nov 7 (Reuters) - U.S. corn and soybean futures rose on Thursday, one day ahead of a key U.S. government report, due to strength in the cash market as well as signs of firm demand on the export market, traders said.
Wheat futures were mixed, with Chicago Board of Trade soft red winter wheat following corn but Kansas City Board of Trade hard red winter wheat and MGEX spring wheat contracts pressured by abundant supplies.
Slow country movement of both corn and soybeans as harvest wound down buoyed prices, which also were rebounding from recent lows.
"With the farmer off of two or three years of record income, he is in a position where he is able to store a lot of crop," said Greg Grow, director of agribusiness at brokerage Archer Financial Services. "As we approach the end of harvest and the farmer is not content with the price, there is a little bit of a need to bid up the cash market to find levels where farmers are willing sellers."
However, most traders were reluctant to stake out big positions ahead of the U.S. Agriculture Department's November crop production and supply/demand reports on Friday. Analysts expect the government to raise the 2013 U.S. corn harvest estimate to a new record and to show a tripling of U.S. ending stocks.
The expectations of a big crop were capping rallies.
"We are continuing to see harvest pressure on corn, and there are estimates of an even bigger crop," said Vanessa Tan, an investment analyst at Phillip Futures.
The November report has taken on extra significance for grain markets after the USDA cancelled its October estimates due to the government shutdown.
At 10:32 a.m. CST (1632 GMT), CBOT December corn was up 1 cent at $4.22-1/4 a bushel. Corn futures hit their lowest since Aug. 26, 2010 during overnight trading.
CBOT soybeans for January delivery were 9-1/2 cents higher at $12.64-1/2 a bushel. The front-month November contract , which expires next week, was up 13 cents at $12.76 a bushel.
Traders said front-month soybeans were receiving extra support from heavy commercial stopping of deliveries.
USDA said on Thursday morning that export sales of corn were 1.72 million tonnes in the latest reporting week, topping forecasts for 1 million to 1.3 million tonnes. Soybean export sales of 1.04 million were near the high end of expectations for 800,000 to 1.1 million tonnes.
CBOT soft red winter wheat for December delivery was up 2 cents at $6.55-1/4 a bushel while KCBT December hard red winter wheat dropped 3/4 cent to $7.15-3/4 a bushel and MGEX December spring wheat was down 1-1/4 cents at $7.11 a bushel.
Prices at 10:34 a.m. CST (1634 GMT)
LAST NET PCT YTD
CHG CHG CHG
CBOT corn 422.25 1.00 0.2% -32.9% CBOT soy 1279.25 16.25 1.3% -8.2% CBOT meal 404.70 7.90 2.0% 9.3% CBOT soyoil 40.40 -0.74 -1.8% -30.0% CBOT wheat 655.00 1.75 0.3% -17.5% CBOT rice 1566.00 11.50 0.7% 11.9% EU wheat 204.00 2.00 1.0% -19.2% US crude 94.16 -0.64 -0.7% 3.0% Dow Jones 15,695 -52 -0.3% 35.6% Gold 1309.90 -7.89 -0.6% -7.7% Euro/dollar 1.3387 -0.0123 -0.9% 0.3% Dollar Index 81.0010 0.5180 0.6% 2.5% Baltic Freight 1593 -9 -0.6% -10.2%
In U.S. cents, benchmark contracts, except EU wheat (euros) and soymeal (dollars). CBOT wheat, corn and soybeans per bushel, rice per hundredweight, soymeal per ton and soyoil per lb.