Corn, soy slip further on improved supply outlook, stronger US dollar

Chicago corn and soybean futures fell for a fourth straight session on Tuesday as massive U.S. harvests continued to pour supplies onto the market and forecasts of rain in Brazil improved production prospects there.

Wheat futures also slipped after the U.S. Department of Agriculture (USDA) raised its outlook for global wheat stocks on Friday, but found some support from concerns over Black Sea production and shipments.

Pressuring all three was a sharp rise in the U.S. dollar this month that has made U.S. crops costlier for overseas buyers with other currencies. DXY

FUNDAMENTALS

* The most-active corn contract on the Chicago Board of Trade (CBOT) ZC1! was down 0.4% at $4.06-3/4 a bushel at 0127 GMT, with CBOT soybeans ZS1! falling 0.5% to $9.91-1/4 a bushel and wheat ZW1! slipping 0.5% to $5.82-1/2 a bushel.

* Corn and soybeans have fallen around 7% from highs around the start of the month and are pushing towards four-year lows. Wheat held up better and is little-changed this month.

* The USDA, in a monthly report on Friday, raised its estimate of U.S. corn production and trimmed its forecast of U.S. soybean output. The country is set for its second-biggest corn harvest and its biggest soybean crop.

* Meanwhile, forecast rain in Brazil is set to break a dry period that hampered planting, with only 8.2% of the total expected soybean area sown by last Thursday compared to 17% at the same time last season, consultancy AgRural said.

* The United States is the world's largest corn exporter and the No. 2 soybean supplier. Brazil is the biggest soybean producer and a major shipper of corn.

* The USDA report, ongoing U.S. harvest and South American weather forecasts triggered a wave of short selling by speculators that pressured prices, StoneX analyst Bevan Everett said.

* "The South American weather forecasts indicate the dry period has ended... This has allayed additional concerns about lost acres and lost yields in Brazil and Argentina," he added.

* In wheat, traders are concerned about Russia, the biggest shipper, where export prices rose last week in anticipation of lower supply.

* The Russian government has also set a minimum price and a higher export duty to limit shipments, but traders say that these measures don't appear to be as restrictive as some had feared.

MARKETS NEWS

* U.S. stocks ended higher with a boost from technology shares amid light Columbus Day trading on Monday, while crude prices dipped as investors parsed signs of economic softness in China and girded themselves for a string of high-profile corporate earnings.