GRAINS-Wheat extends gains on short covering, war risk

By Heather Schlitz

CHICAGO, Dec 24 (Reuters) - Chicago Board of Trade wheat futures rose for a fifth session on Wednesday as worries about war escalation in the Black Sea export zone and severe cold in Russian wheat belts encouraged short-covering before the Christmas break, traders and analysts said.

Corn futures edged up on strong demand and strength from wheat, while soy also ticked higher on positioning ahead of the holidays.

Gains remained moderate, with ample global supplies hanging over grain markets after multi-week price lows last week and light pre-holiday trade.

The most-active wheat contract on the Chicago Board of Trade (CBOT) Wv1 was last up 6 cents at $5.23 per bushel as of 10:00 a.m. CT (1600 GMT).

Russian attacks on Ukrainian ports have reinforced short-covering by investors that typically occurs before the year-end holidays.

"If those headlines become more impactful and disrupt the flow of exports, you'll have a recipe for wheat prices to move higher," said Jason Ward, director at Northstar Commodity. "It's gotten enough headline attention that managed money is tucking some profit away."

While winterkill remains a concern for the Black Sea wheat crop, snow cover should initially protect winter wheat in Russia from frost damage on Wednesday, while snow is set to spread in the next two weeks in Russia and also Ukraine, Commodity Weather Group said in a note.

Bumper volumes expected from ongoing harvests in Argentina and Australia are set to bolster global supply for the rest of the 2025/26 season.

CBOT soybeans Sv1 gained 8 cents to $10.71-3/4 a bushel. Corn Cv1 added 2 cents to $4.49-1/4 per bushel.

In the soybean market, traders remained cautious about the pace of Chinese purchases of U.S. beans under a bilateral trade truce, while forecasters continued to project another record harvest in Brazil this season.

As well as tracking strength in wheat, the corn market remained supported by brisk U.S. exports. EXP/CORN