The first few years of the 21st century brought a series of unprecedented natural disturbances to the southwestern U.S. A severe drought, later tagged as a “global change type drought,” triggered the mortality of 1,000 of native trees. For some species, such as the ponderosa pine, the drought was especially lethal due to high tree densities which were the outcome, in part, of the impacts of past management practices. Already crowded, and competing for water, the drought further weakened the pine trees, making them more susceptible to mortality due to several species of bark beetles that feed on the cambium and in doing so kill them. Entire hillsides were covered with dead and dying trees as the result of the bark beetles, raising concerns that forests would be susceptible to severe wildfires. There was already evidence that fire seasons were starting earlier and lasting longer, and both Arizona and New Mexico experienced their largest fires in recorded history between 2000 and 2015. This unprecedented series of events highlighted the need for better tools to understand and predict fire behaviour under novel conditions.