Dry skies threaten U.S. corn crop as heat wave breaks

The withering U.S. corn crop is gaining some respite from a record heat wave this week but new weather forecasts offered scant signs of the rainfall it urgently needs to avoid the worst drought damage in nearly a quarter century. As the majority of a near-record-size U.S. corn area is now set to enter the key phase of pollination, a period when hot and dry conditions can cause irrevocable damage, the lack of moisture threatens to extend a rally that has already propelled corn prices more than a third higher since mid-June.