
StoneX cut its forecast for Rio Grande do Sul corn output to 4.51 million tonnes from 5.38 million tonnes because of drought. The firm noted that the state often suffers climatic setbacks, and that a dry 2021/22 season cut summer corn to 2.56 million tonnes.
Whether the dryness will also hit the state's soybean crop will become clearer in January and February.
A sharp cut to a major Brazilian corn-producing state tightens exportable corn supplies and supports prices. The loss is regional, so the effect on global prices depends on how much of Brazil's national crop is affected.
After 1,465 past bullish weather events, Corn moved a median +0.2% over 5 sessions (54% higher; middle half -1.4% to +1.9%), and +0.9% over 20.
After 324 past neutral weather events, Soybeans moved a median +0.0% over 5 sessions (52% higher; middle half -1.4% to +1.7%), and +0.7% over 20.
Moves of each commodity's benchmark from the last close before the event. Historical reads pool past events of the same kind; they describe what happened, not what will. Not investment advice.