Real time simulation of 2007 Santa Ana fires

► Two Santa Ana fires are simulated using coupled atmosphere–fire WRF–Sfire model. ► Computational performance allows for real-time fire forecasting. ► Santa Ana winds and the fire-head spread forecasts compare well to observations. ► WRF–Sfire results look promising with potential to complement currently used operational fire spread prediction. In this study we test the feasibility of using a coupled atmosphere–fire model for real time simulations of massive fires. A physics-based coupled atmosphere–fire model is used to resolve the large-scale and local weather as well as the atmosphere–fire interactions, while combustion is represented simply using an existing operational surface fire behavior model. This model combination strikes a balance between fidelity and speed of execution. The feasibility of this approach is examined based on an analysis of a numerical simulation of two very large Santa Ana fires using WRF–Sfire, a coupled atmosphere–fire model developed by the Open Wild Fire Modeling Community (OpenWFM.org). The study demonstrates that a wind and fire spread forecast of reasonable accuracy was obtained at an execution speed that would have made real-time wildfire forecasting of this event possible.