SINGAPORE  - Chicago wheat futures climbed for a third consecutive session on Wednesday to a one-week top as declining condition of the U.S. crop and tightening supplies in the Southern Hemisphere underpinned prices.

Corn lost ground, giving up some of Tuesday's gains, while soybeans advanced for a second session.

The most-active wheat contract on the Chicago Board Of Trade was up 0.1% at $5.12-1/2 a bushel, as of 0336 GMT, after hitting its highest since Nov. 12 at $5.17-1/4 a bushel.

Corn gave up 0.1% at $3.69-1/2 a bushel, having closed about 0.6% firmer in the previous session, while soybeans Sv1 added 0.2% at $9.13-1/2 a bushel, having closed 0.1% higher on Tuesday.

The U.S. Department of Agriculture (USDA) late Monday rated 52% of the U.S. winter wheat crop as good-to-excellent, down from 54% the previous week. Analysts on average had expected a decline of only one percentage point.

"The wheat crop is Australia keeps shrinking and we have had a downgrade in production outlook for Argentina," said a Singapore-based grains trader.

Argentina's 2019/20 wheat harvest is estimated at 18.5 million tonnes, down from a previous forecast of 18.8 million tonnes, due to an outbreak of harmful Fusarium fungi, the Buenos Aires Grains Exchange said in a report last week.

Commodity brokerage INTL FCStone earlier this month said a poll of its clients estimated Australian wheat production during the 2019/20 season would be nearly 20% lower than official estimates.

The corn market has been supported by strong demand for U.S. supplies.

The USDA on Tuesday said private exporters sold 191,000 tonnes of U.S. corn to unknown destinations, following sales of an additional 132,000 tonnes a day earlier.

"Brazil has priced itself out of the market but worldwide there are ample supplies of corn," the trader said. "We don't see buyers chasing higher prices."

The USDA had said on Monday that the U.S. corn harvest was 76% complete, below analysts' forecasts of 77% and well below the five-year average of 92%.

The agency also stated that the U.S. soybean harvest was 91% complete, matching an average of trade expectations but below the five-year average of 95%.

Commodity funds were net buyers of CBOT corn, wheat, soyoil and soymeal futures contracts on Tuesday and net even in soybean futures, traders said.

 

(Reporting by Naveen Thukral, Editing by Sherry Jacob-Phillips) ((naveen.thukral@thomsonreuters.com; +65-6870-3829; Reuters Messaging: naveen.thukral.thomsonreuters.com@reuters.net))