Corn and wheat rise on hot weather, fall in crop ratings

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USDA corn, soybean and wheat ratings fall from the previous week

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Hot weather in the U.S. Midwest could damage soybean and corn crop

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Wheat rebounds from contract lows

(Updates prices)

By Renee Hickman

CHICAGO, Aug 27 (Reuters) - Chicago Board of Trade corn, soybean and wheat futures strengthened on Tuesday, as a spell of hot weather hit the U.S. Midwest and the market took in weekly crop ratings from the U.S. Department of Agriculture, which all fell from last week.

The most active corn contract on the Chicago Board of Trade ended up 6-1/4 cents at 3.92-3/4 a bushel, while soybeans settled 5-3/4 cents higher at $9.86-1/2.

Wheat rose 10-1/2 cents to finish at $5.35-1/2 a bushel.

The USDA's weekly crop progress and condition report, released on Monday after trading ended, showed corn, soybean and wheat ratings below analysts' expectations.

The government agency rated 65% of the U.S. corn crop as good to excellent, down from 67% the prior week, while analysts surveyed by Reuters on average had expected only a one-point drop.

A heatwave and lack of rainfall in large parts of the U.S. Midwest could damage the soybean crop during its key development stage, leaving industry players uncertain about projected record yields.

"With this heat that’s hitting Iowa and surrounding, we're starting to get a little bit of interest in the market," said Karl Setzer, Partner at Consus Ag Consulting.

The extreme heat in the central U.S. was expected to moderate as the week progresses, according to Commodity Weather Group.

Setzer said short covering also lent support to corn and soybeans.

In wheat, he noted the grain had rebounded after hitting contract lows earlier in the morning. Wheat was oversold, causing buyers to jump back into the grain, he said.

Elsewhere, recent rains in Argentina's agricultural heartland were not enough to boost the country's wheat crop, which has withered on lack of precipitation, the Rosario Grains Exchange said on Monday. (Reporting by Renee Hickman, Additional reporting by Naveen Thukral and Sybille de La Hamaide; Editing by Cynthia Osterman)