Rains expected in the northwestern Corn Belt this week should limit harvest progress, while other areas will see drier weather.
The benchmark CBOT December corn contract settled up 1/4 cent at $3.37-1/4 per bushel after encountering chart-based resistance above its 50-day moving average of $3.38.
Ahead of the US Department of Agriculture's weekly crop progress report, analysts surveyed by Reuters expected the government to report the US corn harvest as 11 percent complete, up from 5 percent a week ago.
Analysts expected the USDA to leave corn ratings unchanged with 74 percent of the crop good-to-excellent.
The USDA reported export inspections of US corn in the latest week at 1,285,034 tonnes, in line with trade expectations for 1.0 million to 1.3 million tonnes.
The USDA said private exporters sold 191,000 tonnes of US corn to Mexico for 2016/17 delivery.
China's Dalian Commodity Exchange said on Sunday it will add three delivery locations for its corn future contracts in the country's northeast, in Heilongjiang province, Jilin province and Inner Mongolia.