December corn opened 11 1/2 cents lower on the session at 769 and established an early range of 762 to 782 on fair volume. Prices rebounded quickly from today's lower open. Floor traders indicate that there is a great deal of nervousness over weather forecasts this morning with expectations that prices may swing back and forth as updated forecasts are released depending on the level of heat and the amounts of rains that are projected for later next week. This morning's forecasts were less hot and dry on balance than those released during the trading session yesterday, although they are still calling for above normal temperatures as next week wears on with the focus of higher temperatures being in the western corn belt. Floor traders note that funds led the way in corn late in the session yesterday, buying a total of over 12,000 contracts, and the market is expected to be very sensitive to indications of fund buying today. The USDA issued its latest Export Sales Report this morning. Net old crop sales for corn were 325,900 tonnes and new crop sales were 302,500 tonnes. Sales of 239,000 tonnes are needed each week to reach the current USDA projection for old crop exports. Total sales to date stand at 96.4% of the projected total compared to a 5-year average of 91.9%. Japan was the biggest buyer.