CHICAGO, July 7 (Reuters) - Chicago Board of Trade corn futures climbed to one-month highs on Tuesday, buoyed by forecasts for crop-stressing heat in the Midwest later this month and talk of renewed Chinese demand for U.S. grains, analysts said.

• Additional support stemmed from higher crude oil CLc1 prices, following reports of attacks on vessels near the Strait of Hormuz. Corn and soybeans are widely used for biofuel. O/R

• CBOT September corn CU26 settled up 5-1/2 cents at $4.43-3/4 per bushel.

• CBOT new-crop December corn CZ26 ended up 6-1/2 cents at $4.64-1/4 a bushel after reaching $4.64-3/4, its highest since June 3.

• Updated midday weather models pointed to potentially stressful heat in the western Midwest and Plains through the middle of July, analysts said, when much of the U.S. corn crop will be pollinating.

• Weekly U.S. corn condition ratings held steady, the Department of Agriculture reported late on Monday, with 67% of the crop rated good or excellent, while the equivalent soybean score edged down 1 percentage point to 64%.

• Analysts noted market talk that China was seeking offers for U.S. soybeans and corn. China's state-owned trader COFCO bought at least five cargoes of U.S. soybeans on Monday, two U.S. traders with knowledge of the deals told Reuters.

• Commodity funds appeared to return as buyers of CBOT grains, traders said, after slashing longs and flipping to a net short position in CBOT corn futures during June.