GRAINS-Soybeans head for biggest weekly loss in a year

* Soybeans down over 5 pct this week, most since July 2016

* Improving Midwest weather hits soybean prices

* Corn also lower on week, focus shifts to USDA August report

* Wheat near 7-week low; slow exports, big Russia crop weigh

(Updates with European trading, changes byline/dateline) PARIS/SINGAPORE, Aug 4 (Reuters) - Chicago soybean futures slipped on Friday, holding near a one-month low and poised for the biggest weekly fall in a year as crop-friendly weather in the United States dampened prices. Chicago wheat edged higher, consolidating above a seven-week low but still on track for a fourth straight week of declines as ample global supplies and disappointing U.S. weekly exports weighed on the market. Corn was also slightly higher on the day but set for a drop for the second week in a row as improving weather conditions offset support from private harvest estimates that came below the U.S. government's official forecast. The Chicago Board of Trade's most-active soybean contract was down 0.2 percent at $9.58-1/4 a bushel by 0959 GMT, close to Thursday's low of $9.55-1/2, a level not seen since June 30. It has dropped 5.4 percent so far this week, the largest decline since July 2016. Soybean prices have been pressured by forecasts of showers in Iowa and Minnesota, the second and third-biggest soy-producing states in the United States. Soybeans this month are setting pods, the key stage for determining yields. "Weather forecasters' predictions are largely being realised with more rain and cooler temperatures," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia in Sydney. "The forecasters also expect more of the same at different times for the next week or so. August, the danger period for soybean crops, is looking benign for now." CBOT corn was up 0.4 percent at $3.79-1/4 a bushel but was down more than 2 percent over the week. Private analytics firm Informa Economics on Thursday pegged the U.S. corn yield at 165.9 bushels per acre (bpa), trade sources said, joining brokerage INTL FCStone in pegging yields below the USDA's trend-based forecast of 170.7 bpa. Market attention is turning towards the USDA's monthly supply and demand report on Aug. 10 in which it will update its corn yield projection including first data from field surveys. But the full impact of a hot and dry summer in the U.S. Midwest is unlikely to show up in the government's next estimate of the U.S. corn crop as it typically makes just small adjustments to its harvest outlook during August. CBOT wheat was up 0.3 percent at $4.59 a bushel, near Thursday's seven-week low of $4.54-1/4 and down 4.6 percent so far this week. The U.S. Department of Agriculture reported export sales of U.S. wheat in the latest week at 145,500 tonnes, a marketing year low that fell below a range of trade expectations for 300,000 to 500,000 tonnes. This added pressure from rising expectations for harvest production in Russia, a leading wheat exporter.

Prices at 0959 GMT

Last Change Pct End Ytd Pct Move 2016 Move CBOT wheat 459.00 1.25 0.27 408.00 12.50 CBOT corn 379.25 1.50 0.40 352.00 7.74 CBOT soy 958.25 -2.25 -0.23 1004.00 -4.56 Paris wheat Dec 168.75 0.50 0.30 175.00 -3.57 Paris maize Nov 164.00 0.25 0.15 170.00 -3.53 Paris rape Nov 365.25 -0.75 -0.20 383.25 -4.70 WTI crude oil 48.67 -0.36 -0.73 53.72 -9.40 Euro/dlr 1.19 0.00 0.12

Most active contracts - Wheat, corn and soy US cents/bushel, Paris futures in euros per tonne

(Reporting by Naveen Thukral in Singapore and Gus Trompiz in Paris; Editing by Greg Mahlich)