XBeach (Roelvink et al. 2009), a process-based numerical model designed to estimate erosion under extreme events is calibrated and compared against a large scale lab experiment. The model is capable of generating seiching modes observed in the tank and shows good agreement between modeled and measured waves once the model is calibrated to individual events. Modeled waves are sensitive to γ, the breaking parameter, and c_f, the coefficient of friction. Modeled run-up was underestimated compared to observations due to the omission of incident band energy that accounted for roughly 40% of the run-up signal. Despite this, modeled dune erosion compared well with observations after calibration. Erosion results were sensitive to the critical slope parameters, dryslp/wetslp, and depth limiters, h_min and h_switch.