GRAINS-Winter wheat contracts slump on big supply, spreads

(Rewrites throughout with U.S. market open, adds quotes, updates prices, changes byline, changes dateline from SINGAPORE/PARIS)

CHICAGO, Nov 8 (Reuters) - U.S. winter wheat futures fell for a second straight day on Wednesday on ample supplies of low-protein grain and subdued demand, traders said.

Corn and soybeans were narrowly mixed as investors squared positions ahead of the U.S. Agriculture Department's monthly crop supply and demand reports on Thursday.

Intermarket spreading weighed on hard and soft red winter wheat contracts as traders sold the lower-protein varieties and bought higher-protein Minneapolis spring wheat futures.

"We've got plenty of wheat, but we don't have plenty of the right kind. The wheat market is developing a very short protein problem," said Roy Huckabay, analyst with Linn & Associates.

Chicago Board of Trade December SRW wheat fell 4-1/4 cents to $4.23 a bushel by 11:23 a.m. CST (1723 GMT) while K.C. December HRW wheat dropped 3 cents to $4.23-1/2 a bushel. Minneapolis December wheat futures rose 3-1/4 cents to $6.38 a bushel.

Weak demand for lower-protein U.S. wheat in export markets also weighed on winter crop futures.

Egypt's GASC, the world's top state buyer of wheat, said it bought 120,000 tonnes of Russian wheat in a snap tender.

Meanwhile, Turkey's state grain board TMO announced a tender for 230,000 tonnes of European milling wheat.

"We're not competitively priced on the world market so any time we try to rally it gets snuffed out by the realization that we're not moving wheat at the current price levels," said Brian Hoops president of Midwest Market Solutions, a brokerage and commodity marketing advisory service.

Corn and soybean prices fluctuated near previous levels as traders awaited Thursday's USDA report, which is expected to show higher corn yields, lower soybean yields and still-ample global supplies of grains and oilseeds.

CBOT December corn rose 3/4 cent to $3.48-1/2 a bushel while January soybeans rose 3/4 cent to $9.96-3/4 a bushel.

China imported 5.86 million tonnes of soybeans in October, down 28 percent from the previous month and well below market expectations, customs data showed on Wednesday, after some shipments were delayed.

But the country will commit to buy more U.S. soybeans during President Donald Trump's visit to Beijing this week, a U.S. industry official said, underlining the importance of trade in farm goods even as tensions grow between the world's top two economies.

(Additional reporting by Naveen Thukral in Singapore and Sybille de La Hamaide in Paris; Editing by David Evans and Susan Thomas)