CHICAGO, July 29 (Reuters) - Chicago Board of Trade corn futures fell on Tuesday for a third straight session as forecasts for cooler Midwest temperatures this week and periodic rains reinforced expectations for ample U.S. harvests, analysts said.
CBOT September corn CU25 settled down 4-1/2 cents at $3.89-1/4 per bushel after recording a life-of-contract low at $3.87-3/4. The most-active December contract CZ25 ended down 3 cents at $4.11 a bushel.
The U.S. Department of Agriculture late on Monday rated 73% of the corn crop as good to excellent, down a percentage point from the prior week but still the highest rating for this time of year since 2016.
The nearby September corn futures contract CU25 has been falling more heavily than deferred contract months, typically a sign of soft cash markets. The corn harvest is under way in the far southern fringes of the crop belt, including Texas and Louisiana, weekly USDA data showed.
Hot temperatures and a lack of rain could reduce Ukraine's 2025 corn harvest by 2 million metric tons, Ukrainian agricultural producers' union, UAC, said. Ukraine is the world's fourth-largest corn exporter.