Mapping the occurrence of post-fire flooding and debris flow is crucial for 1) integrating observations into models used to define rainfall thresholds for early warning, 2) understanding patterns of inundation, and 3) improving models for predictive hazard assessment. Despite the critical role mapping plays in post-fire hazard assessment and early warning, there has not been a standardized approach for mapping floods and debris flows with consistent protocols. This project will develop and test a mapping schema using ArcGIS Collector, a mobile mapping platform. We will test the approach in five areas that burned in 2020 through a collaboration between the USGS and the Oregon Department of Geology and Mineral Industries. The end [...]