The UCSB Climate Hazards Center's July update uses North American Multimodel Ensemble forecasts to project a possible dry October-December 2020 and March-May 2021 rainy season in East Africa. The authors note substantial uncertainty and that Greater Horn of Africa already faces widespread food insecurity.
East African drought mainly affects local food security and regional import demand rather than global grain prices, so the price impact is limited.
After 445 past neutral weather events, Corn moved a median +0.1% over 5 sessions (52% higher; middle half -1.4% to +1.6%), and +0.7% over 20.
After 224 past neutral weather events, Wheat (SRW) moved a median -0.1% over 5 sessions (46% higher; middle half -1.4% to +1.5%), and +0.4% 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.