U.S. farmers are projected to produce 13.6 billion bushels of corn this year, the U.S. Department of Agriculture said in its World Agricultural Supply and Demand Estimates (WASDE) report last week. But both precipitation and temperature will determine just how well the crops grow.

U.S. corn production is projected at 13.6 billion bushels, down 586 million from the record 2014/15 crop with a lower forecast area and yield. The U.S. corn yield is projected at 166.8 bushels per acre, down 4.2 bushels from the 2014/15 record based on a weather-adjusted yield trend that assumes normal summer weather. The corn crop could be the third largest on record, said Chad Hart, crop markets specialist at Iowa State University.

The...