(Recasts with closing prices, adds details)
By Mark Weinraub
CHICAGO, July 14 (Reuters) - U.S. soybean futures fell 3.8 percent on Thursday, giving up early gains after new weather forecasts boosted expectations of a robust harvest in the United States.
Corn and wheat futures also closed lower after rallying to `7two-week highs earlier in the session.
The latest outlooks dialed back the amount of time next week the Corn Belt will suffer from scorching temperatures. More rain was also added, which will help protect the crop from the searing heat.
“It is still going to get hot next week but ... the extended pattern is not as intimidating as it was yesterday,” said Bill Gentry, a broker at Risk Management Commodities in Lafayette, Indiana.
Chicago Board of Trade November soybeans futures settled down 43 cents at $10.62-1/4.
CBOT December corn futures dropped 5 cents to close at $3.64-3/4 a bushel.
A better-than-expected export report from the U.S. Agriculture Department on Thursday morning limited the sell-off in corn.
The USDA said old-crop export sales of corn came in at 667,800 tonnes last week and new-crop export sales were 687,800 tonnes. Both figures topped the high end of a range of market forecasts.
CBOT September soft red winter wheat futures were down 5-3/4 cents at $4.34 a bushel.
Plentiful global supplies and expectations that big harvests in the United States and Russia will add to the glut added to the bearishness in the wheat market.
“Early harvest activity has indicated Russian yields are even better than anticipated,” Commonwealth Bank of Australia analyst Madeleine Donlan said. “Russia’s winter wheat output is expected to be a record this year, as are Russian exports. U.S. wheat will face plenty of competition in the season ahead.” (Additional reporting by Naveen Thukral in Singapore and Nigel Hunt in London; Editing by Steve Orlofsky and Peter Cooney)