* Contract lows in most corn contacts as supplies weigh
* Soybeans turn lower, following corn
* Improving South American weather adds pressure
* Wheat firms on short-covering, softer dollar
(New throughout; updates prices, market activity and comments; new byline, changes dateline from previous HAMBURG) CHICAGO, Nov 14 (Reuters) - U.S. nearby corn futures fell to the lowest levels in two months on Tuesday, pressured by ample supplies from the nearly completed harvest of the second-largest domestic corn crop on record, traders said. Soybeans declined as improving crop weather in South America added to bearish sentiment. But wheat futures firmed. As of 12:30 p.m. CST (1830 GMT), Chicago Board of Trade December corn was down 4-3/4 cents at $3.37-1/2 per bushel after dipping to $3.37-1/4, a contract low and the lowest spot price on a continuous chart since Sept. 12. CBOT January soybeans were down 6-1/2 cents at $9.67-3/4 a bushel while December wheat was up 3-1/4 cents at $4.27-1/2. Technical selling in corn accelerated as the December contract slipped below its previous low of $3.40-3/4, which was set last week after the U.S. Department of Agriculture raised its estimate of the U.S. corn yield to 175.4 bushels per acre, a record high. The government put corn production at 14.6 billion bushels, second only to the 2016 crop. "It's a crop that is bigger than what they thought. The end-user has his hands in his pockets, and world competition is still keen. That all adds up," said Don Roose, president of Iowa-based U.S. Commodities. The USDA late Monday said the corn harvest was 83 percent complete and the soybean harvest was 93 percent complete.
Better weather in South America, including beneficial rains this week in parts of Brazil, bolstered global production prospects. "The rains in Mato Grosso yesterday were enough to convince people that the rest of the Brazilian planting progress will be wrapped up in the next few weeks ... If soybeans are planted in timely matter, then the second-crop corn should not have any issues going into the ground," said Terry Reilly, senior commodity analyst with Futures International. However, mostly dry conditions were expected next week in Argentina's main agricultural area, which could delay soybean planting. Broad weakness in commodities added pressure. The 19-market Thomson Reuters CoreCommodity Index was down 1.3 percent, hitting its lowest since Nov. 3. CBOT wheat bucked the weak trend, firming on technical buying including short-covering, and a weaker dollar, which in theory makes U.S. wheat more attractive on the global market. "On wheat, export competitiveness will be a critical factor in the near future, especially between the U.S. and the Black Sea region before the Black Sea slows down for the winter," said Graydon Chong, senior commodity analyst with Rabobank.
CBOT prices as of 12:31 p.m. CST (1831 GMT):
Net Pct Volume
Last change change
CBOT wheat WZ7 427.50 3.25 0.8 74787 CBOT corn CZ7 337.50 -4.75 -1.4 174517 CBOT soybeans SF8 968.00 -6.25 -0.6 79589 CBOT soymeal SMZ7 309.90 -1.40 -0.5 42650 CBOT soyoil BOZ7 34.10 -0.23 -0.7 41950
NOTE: CBOT December wheat, December corn and January soybeans shown in cents per bushel, December soymeal in dollars per short ton and December soyoil in cents per lb.
(Additional reporting by Michael Hogan in Hamburg and Naveen Thukral in Singapore, editing by Hugh Lawson and David Gregorio)