Wildfires can increase the frequency and magnitude of catastrophic debris flows. Integrated, proactive naturalhazard assessment would therefore characterize landscapes based on the potential for the occurrence and interactions of wildfires and postwildfire debris flows. This chapter presents a new modeling effort that can quantify the variability surrounding a key input to postwildfire debris‐flow modeling, the amount of watershed burned at moderate to high severity, in a prewildfire context. The use of stochastic wildfire simulation captures variability surrounding the timing and location of ignitions, fire weather patterns, and ultimately the spatial patterns of watershed area burned. Model results provide for enhanced estimates of postwildfire debris‐flow hazard in a prewildfire context, and multiple hazard metrics are generated to characterize and contrast hazards across watersheds. An area in northern New Mexico, USA, is presented as a case‐study location, where postwildfire debris flows are a salient hazard and where land managers are actively pursuing mitigation efforts. Modeling results are described in terms of informing mitigation efforts. Limitations and future directions are presented.