(Updates with closing prices, NOPA results)
CHICAGO, Oct 16 (Reuters) - Chicago Board of Trade soybean futures weakened on Monday, dipping below the $10-per-bushel threshold the market hit for the first time in 2-1/2 months last week.
"Soybeans are lower, giving back some of last week's gains on profit taking," Farm Futures analyst Bryce Knorr said in a note to clients.
Soybean futures had risen 2.9 percent last week, supported by the U.S. Agriculture Department's surprise cut to its harvest yield forecast.
Corn futures also fell on Monday, pressured by forecasts for warm, dry weather in the Midwest crop belt, which should allow farmers to pick up the pace of harvesting following a slow start. Weaker-than-expected weekly export data added to the weight hanging over the corn market.
Wheat futures dropped on technical selling after hitting a one-week high early in the trading session.
CBOT November soybean futures settled down 9-1/4 cents at $9.91 a bushel.
"The U.S. market has been a key driver of soybean prices as the USDA reduced its yield forecast," said Phin Ziebell, agribusiness economist at National Australia Bank. "But it has not changed the fundamental picture significantly."
A weaker-than-expected report on the pace of crushing at U.S. soy processors added to the bearish tone. The National Oilseed Processors Association said the September soybean crush totalled 136.419 million bushels. Analysts had been expecting 138.071 million bushels.
Declines were kept in check by strong demand. The USDA said weekly export inspections of soybeans totalled 1.770 million tonnes, topping forecasts that ranged from 1.100 million to 1.400 million.
USDA said corn export inspections were 322,672 tonnes and wheat export inspections were 322,860 tonnes for the week ended Oct. 12. Both came in below the low end of market expectations.
CBOT December corn futures were 2-1/4 cents lower at $3.50-1/2 a bushel and CBOT December soft red winter wheat was down 3 cents at $4.36-1/2 a bushel.
Investors were awaiting an update on soybean and corn harvesting in the USDA's weekly crop progress report due on Monday afternoon. (Additional reporting by Naveen Thukral in Singapore and Gus Trompiz in Paris; Editing by Jonathan Oatis and Peter Cooney)