Corn futures climbed above $5 per bushel to their highest level since July 2023 as weaker U.S. yield estimates, declining crop conditions, weather risks and disruptions to Black Sea grain shipments pointed to tighter supplies. The Pro Farmer Crop Tour estimated the 2026 U.S. corn yield at 173.2 bushels per acre, below the USDA’s latest forecast of 180.7 bushels, with production projected at 15.34 billion bushels. The USDA said the share of the crop rated good to excellent fell three percentage points to 57% for the week ended August 23. Heat stress and excessive rainfall in parts of the Midwest could further limit yields before harvest. U.S. corn export inspections remained strong, with cumulative shipments up 26% from a year earlier despite weekly shipments easing to 1.3 million tonnes. The rally also reflects broader weather and geopolitical risks, including El Nino and disrupted shipments linked to the Russia-Ukraine war. Futures and commodities expert Zafer Ergezen said El Nino effects had emerged from June and could continue until the beginning of next year. He also cited oil prices and demand for corn-based biodiesel as additional support, and said he did not expect a deep pullback unless oil prices declined or a lasting peace deal was reached between the United States and Iran.