 This paper proposes a new approach to incorporate synthetic aperture radar, SAR, data into hydrological models to improve flood prediction. The proposed methodology uses a particle filter to assimilate SAR data into a coupled hydrologic hydraulic model. The model is then used to simulate water levels and discharges, which are compared to actual observations. The results show that the proposed methodology can significantly reduce uncertainty in water level and discharge predictions. Additionally, the proposed methodology can also update the model state and inputs, leading to improved model performance. This article was authored by P Matt Gen, M Montaneri, our hostake, and others.