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Dryness in Argentina lifts 2023 soybean supply concerns

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U.S. wheat faces threat from extreme winter; corn climbs

CHICAGO, Dec 21 (Reuters) - Chicago wheat futures climbed on Wednesday, as forecasts for temperatures well below freezing across the U.S. Midwest threatened winter crops heading into the holiday weekend.

Corn and soybeans inched higher, supported by firmer wheat and weather conditions in South America.

The most-active wheat contract on the Chicago Board of Trade (CBOT) was up 20-1/4 cents to $7.70-3/4 a bushel by 11:39 a.m. CST (1739 GMT), after hitting $7.74-1/2, its highest level since Dec. 2.

Corn added 7-1/2 cents to $6.59-3/4 a bushel, after touching 6.62-1/4, its highest level since Dec. 1.

Soybeans rose 1-3/4 to $14.81-1/2 a bushel.

Hard red winter wheat in the U.S. Plains, as well as soft red wheat east of the Mississippi River, could face winterkill, as temperatures drop further on Friday.

"It's going to get cold. There is no snow cover. They're on the (temperature) threshold," said Mark Schultz, chief market analyst at Northstar Commodity.

The full effect of the damage wont be immediately known, which could be the reason futures' gains are muted.

"In terms of a crop scare rally, this is pretty disappointing," said Joe Vaclavik, president of Standard Grain.

Corn and soybeans found support in higher wheat futures, while recent rains in parts of Argentina boosted crop prospects, adding weight to U.S. futures.

Extended forecasts for Argentina, the world's leading exporter of processed soy, show a return to dry conditions, adding to a delay in soy planting in parts of the South American nation that could erode yields.

Brazil, the world's biggest soybean exporter, is far less impacted by the dry weather, and is expected to begin harvesting soybeans by late January.

"Its just choppy trade," Vaclavik said. "It kind of feels like we're just holding our ground until we see what that South American crop looks like."

China's November soybean imports from the United States fell 6.9% from a year earlier, data showed on Tuesday, after low U.S. river levels slowed shipping of beans to ports for export.

The Asian nation, which is the world's biggest soybean buyer, imported 3.38 million tonnes of the oilseed from the United States last month, down from 3.63 million tonnes a year earlier, according to the General Administration of Customs. (Reporting by Christopher Walljasper in Chicago; additional reporting by Naveen Thukral and Sybille de La Hamaide; editing by Paul Simao)