The IRI October Quick Look puts mid-October Pacific sea-surface temperatures about 1 degree C below average, consistent with La Niña. The official CPC/IRI outlook gives an 85% chance of La Niña for winter, and a La Niña advisory is in effect.
A likely winter La Niña increases the chance of drought in South America and the US, a supply risk that tends to support soybean and corn prices.
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 1,079 past bullish weather events, Soybeans moved a median +0.3% over 5 sessions (54% higher; middle half -1.4% to +2.0%), and +0.9% 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.