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Corn futures lowest since August on coming El Nino arrival

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Black Sea export deal hopes drag wheat to 18-month low

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Soybeans dragged by falling corn, wheat

CHICAGO, March 9 (Reuters) - Chicago corn futures hit their lowest price since August on Thursday on expectations that the El Nino climate phenomenon could boost U.S. crops and concerns about rising interest rates.

La Nina has ended, the National Weather Service's Climate Prediction Center said on Thursday, and El Niño could possibly form during summer 2023 and persist through the fall.

El Nino is a warming of ocean surface temperatures in the eastern and central Pacific which could boost precipitation, brightening the outlook for U.S. crops.

"There a belief that La Nina is dying and that our growing conditions in the Midwest may be under El Nino conditions, which are favourable for growth," said Don Roose, president of U.S. Commodities.

Corn was also hit by traders closing long positions after the Federal Reserve said this week it would continue to increase interest rates, analysts said.

Additionally, Brazil's food supply and statistics agency Conab raised its

corn crop estimate

, lessening worries about Argentina's drought-hit harvest.

Wheat hit a new 18-month low on poor demand for U.S. exports.

Soybeans also closed lower. The USDA reported net cancellations of 23,200 tonnes in old-crop U.S. soybean export sales in the week ended March 2, below expectations.

The U.S. wheat market has been under pressure from Russian export competition and expectations that a wartime grain corridor from Ukraine will be extended beyond this month, increasing available global supplies.

But the Kremlin said on Thursday that "a lot of questions" remain over the Black Sea grain deal.

The most-active corn contract on the Chicago Board of Trade (CBOT) settled down 14 cents at $6.11-1/2 a bushel. The contract touched a low of $6.10-1/4 during the session, the lowest since August.

The most-active wheat futures contract closed 21.75 cents lower at $6.65-3/4 a bushel, while the benchmark May soybean futures contract settled down 7 cents at $15.10-3/4 a bushel. (Reporting by Cassandra Garrison in Chicago; Editing by Paul Simao)