In California, a changing climate has made autumn feel more like summer, with hotter, drier weather that increases the risk of longer, more dangerous wildfire seasons, according to a new Stanford-led study. The paper, published in Environmental Research Letters, provides insights that could inform more effective risk mitigation, land management and resource allocation. “Many factors influence wildfire risk, but this study shows that long-term warming, coupled with decreasing autumn precipitation, is already increasing the odds of the kinds of extreme fire weather conditions that have proved so destructive in both northern and southern California in recent years,” said study senior author Noah Diffenbaugh, the Kara J Foundation professor at Stanford’s School of Earth, Energy & Environmental Sciences.