Little evidence of avoided yield loss in US corn when short-term forecasts correctly predict extreme heat

Successful agricultural adaptation to extreme heat has the potential to avert large crop losses and improve food security. Because adaptation is costly, accurate weather forecasts have the potential to improve targeting of adaptation efforts. To understand the role of short-term (1-7 day) forecasts in reducing heat-related yield loss, we analyze a novel dataset combining corn yields, short-term weather forecasts, and weather realizations in the United States from 2008 to 2021. We find no evidence that forecasts facilitate avoidance of heat-related yield losses on average, and only limited benefits when we allow for forecast benefits to vary with irrigation prevalence. While our results paint a pessimistic picture of in-season adaptation to heat, forecasts may be more valuable for other crops and regions, especially given continuing investment in adaptation technologies.