U.S. corn and soybean futures fell on Monday as forecast rain eased concerns about dryness in the Midwest and traders awaited further clues from a weekly U.S. government crop report.
Wheat was pulled lower by corn and soy while also remaining under pressure from progress in the U.S. winter wheat harvest.
The most active Chicago Board of Trade corn contract was down 2.1 percent at $4.28-1/2 a bushel by 1149 GMT, giving up most of its sharp gains from Friday.
Soybeans were down 1.6 percent at $11.30 a bushel, while wheat slipped 1.1 percent to $4.76 a bushel.
Corn raced higher on Friday amid market worries that patchy rain and rising temperatures could stress Midwest crops in the run-up to the pollination phase.
But weather forecasts were showing some more rain this week after some heavy showers over the weekend, although intense heat was expected in some areas in the week ahead.
"Rains forecast on the Corn Belt should weigh on the market again, in a context where funds remain very long of soybean and corn, pushing them to profit taking," consultancy Agritel said in a market note.
Soybeans have also been supported by Midwest weather risks as well as buoyant export demand as competing supplies from South America have been reduced by rain damage to the Argentine harvest.
However, prices logged their first weekly loss in 10 last week as worries as rally lost momentum.
"You've seen grain prices very low, broadly speaking, because the supply outlook has been really good for a long time. You've seen some concerns recently in soy, which has spilled over into corn as well," said Phin Ziebel, agribusiness economist at National Australia Bank in Melbourne. Investors will be looking at the U.S. Department of Agriculture's weekly crop progress data after the market close on Monday to see if U.S. crops remain mostly in good condition.
Wheat futures have faced headwinds from ample world supplies and reports of good yields in the advancing U.S. winter wheat harvest.
CME Group, which operates the CBOT market, said on Monday it will launch European Union wheat futures on Sept. 12, a long-planned move that will pitch it against Euronext, whose wheat futures are a European benchmark.