* U.S. corn, soybean crop ratings post unexpected drop
* Chicago wheat futures gain for 1st time in 4 sessions
SINGAPORE, July 27 (Reuters) - Chicago soybean and corn futures gained for a second straight session on Tuesday after a weekly U.S. government report showed the condition of both crops unexpectedly deteriorated last week.
Wheat rose after three sessions of decline.
"We are in a typical weather market. Prices are firming after the crop condition report, but if the weather improves the market could give up these gains," said one Singapore-based feed grains trader at an international trading company. "We are just trying to ride it out."
The most-active soybean contract on the Chicago Board Of Trade (CBOT) rose 0.8% to $13.68-1/4 a bushel, as of 0314 GMT, after prices hit a July 12 low of $13.32 a bushel in the previous session.
Corn was up 0.5% at $5.49-1/4 a bushel and wheat climbed 0.3% to $6.79-1/4 a bushel.
The condition of the U.S. corn and soybean crops unexpectedly deteriorated in the latest week, with dryness in growing areas west of the Mississippi River stressing crops, the U.S. Department of Agriculture said on Monday.
The agency said good-to-excellent ratings for corn fell by 1 percentage point to 64% in the week ended July 25, below market expectations.
The soybean crop was rated 58% good-to-excellent, down 2 percentage points from a week earlier, and behind market forecasts.
Spring wheat was rated 9% good-to-excellent, 2 percentage points lower than a week earlier and 1 percentage point below the average of analysts' forecasts.
Meanwhile, Russia's southern region of Krasnodar, one of the largest wheat producing and exporting areas of the country, harvested a record grain crop of 12.4 million tonnes, its governor said on social media.
Commodity funds were net buyers of CBOT corn, soybean and soyoil futures contracts on Monday, and net sellers of wheat and soymeal, traders said. (Reporting by Naveen Thukral; Editing by Subhranshu Sahu)
