GRAINS-Soybeans at 3-wk low on reports of higher yields from early US harvest

* Soybean prices hit lowest since Sept. 13 on higher yields

* Addition pressure on Soybean prices from improved Brazil weather

* Wheat falls for fourth session, corn extends losses

(Adds comment, detail) SINGAPORE, Oct 3 (Reuters) - Chicago soybean futures dropped for a second session on Tuesday, falling to their lowest in almost three weeks as the harvest of a bumper U.S. crop gathers pace amid reported higher yields. Wheat slid for a fourth consecutive session on pressure from a U.S. government forecast of a bigger spring wheat crop despite drought damage. The most-active soybean contract on the Chicago Board of Trade had fallen 0.4 percent to $9.53-3/4 a bushel by 0207 GMT, after dropping earlier in the session to its lowest since Sept. 13 at $9.52-1/2 a bushel. Wheat eased 0.2 percent to $4.44 a bushel and corn declined 0.3 percent to $3.50-1/2 a bushel. The U.S. Department of Agriculture said the U.S. soybean harvest was 22 percent complete by Sunday, slightly behind an average of trade estimates for 25 percent and the five-year average of 26 percent. The corn harvest was 17 percent complete, lagging the five-year average of 26 percent. Brokerage INTL FCStone raised its estimate of the U.S. 2017 corn yield to 169.2 bushels per acre (bpa), from 166.9 bpa in its previous monthly report released Aug. 31. The firm also raised its forecast of the U.S. 2017 soybean yield to 49.9 bpa, from 49.8 bpa previously. The focus is turning to South America where planting for the 2018 soybean crop is underway. "Some of Brazil's driest soybean regions got useful rain over the weekend," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia. "The rain means most Brazilian soybean regions will have enough rain to support rapid planting. Brazil's soybean crops now look more likely to avoid most of the problems that would arise with late planting." In Argentina, a dry spell for the next 10 days should bring some relief to waterlogged fields of soybeans and corn after rains over the weekend added to fears of planting delays, experts said on Monday. Argentina's main grain belt has been inundated with rains in recent months, contributing to a 5.7-percent reduction in the forecast for area planted with soybean in 2017-18, according to the Buenos Aires Grains Exchange The wheat market faced pressure from higher estimates of the U.S. spring wheat crop. The USDA on Friday reported U.S. 2017 production of spring wheat other than durum at 416 million bushels, up from its previous estimate of 402 million bushels and well above analyst estimates.

Grains prices at 0207 GMT

Contract Last Change Pct chg Two-day chg MA 30 RSI CBOT wheat 444.00 -0.75 -0.17% -0.95% 442.16 49 CBOT corn 350.50 -1.00 -0.28% -1.34% 353.60 49 CBOT soy 953.75 -3.50 -0.37% -1.50% 958.54 40 CBOT rice 12.05 $0.03 +0.25% +0.46% $12.56 36 WTI crude 50.44 -$0.14 -0.28% -2.38% $49.20 46


Euro/dlr $1.170 -$0.003 -0.23% -0.92% USD/AUD 0.7813 -0.001 -0.15% -0.26%

Most active contracts Wheat, corn and soy US cents/bushel. Rice: USD per hundredweight RSI 14, exponential

(Reporting by Naveen Thukral; Editing by Joseph Radford)