* Ideal weather in U.S. Midwest pressures corn, soy prices

* USDA on Friday expected to raise outlook for corn, soy crops

* Weekly U.S. wheat export sales below analysts’ estimates (Updates with U.S. trading, changes dateline)

By Tom Polansek

CHICAGO, July 10 (Reuters) – New-crop U.S. corn futures set a contract low for the eighth consecutive session on Thursday as mild weather increased expectations for bumper crops, while new-crop soybeans dropped to a six-month low below $11 a bushel.

The markets have “nothing long term to encourage even short- term gains” amid expectations for an influx of supplies from the autumn harvests, said Rich Feltes, vice president of research for broker RJ O’Brien.

Weather conditions are favorable for crops and farmers are accelerating sales of corn in storage from last year’s harvest, he said.

Analysts expect the U.S. Department of Agriculture on Friday will increase its estimate for U.S. corn production to 13.945 billion bushels, up from 13.935 billion in June, and peg soybean production at 3.774 billion bushels, up from 3.635 billion in June.

“Tomorrow’s report can’t offer much hope for the bulls,” said Sterling Smith, futures specialist for Citi.

Chicago Board of Trade December corn dropped 5 cents to $3.93 a bushel by 11:25 a.m. CDT (1625 GMT) after setting a contract low of $3.92, below Wednesday’s contract low of $3.95.

The contract has lost 12 percent since the USDA, in a quarterly report on June 30, said U.S. corn stocks as of June 1 were 3.5 percent larger than analysts expected.

CBOT November soybeans slipped 6-3/4 cents to $10.97 a bushel after falling earlier in the session to $10.96 a bushel, the lowest since January 31.

September wheat was down 3 cents to $5.48-1/4 a bushel, having dropped to a contract low of $5.47-1/4 a bushel earlier in the session.

The USDA on Thursday said U.S. wheat export sales last week were 338,100 tonnes, below expectations for 400,000 to 635,000 tonnes. Corn export sales of 744,600 tonnes were within expectations for 600,000 to 1.05 million tonnes, and soybean sales of 582,700 tonnes were within expectations for 200,000 to 600,000 tonnes.

Prices at 11:26 a.m. CDT (1626 GMT)                          
 
                              LAST      NET    PCT     
                                        CHG    CHG     
 CBOT corn                  385.50    -5.75  -1.5%   
 CBOT soy                  1236.75    -9.75  -0.8%   
 CBOT meal                  402.10    -4.00  -1.0%   
 CBOT soyoil                 37.31     0.17   0.5%   
 CBOT wheat                 546.50    -4.75  -0.9%   
 
    

 (Additional reporting by Naveen Thukral and Gus Trompiz;
Editing by William Hardy and Dan Grebler)