The CEST model was robust for most cases without further adjustment, and produced maximum MEOWs and MOMs heights comparable to those created by the SLOSH model. However, the maximum inundation extents from CEST are smaller than the extents from SLOSH. We found that the difference in the treatment of the overland bottom friction due to the variation of land cover was the major factor to cause the different MOMs from SLOSH and CEST. In CEST, the effects of land cover on bottom friction are considered by introducing varying Manning’s coefficients based on the national land cover dataset, while the land cover effect is not considered in SLOSH. A slip coefficient is used to adjust the surge height and inland extent in the SLOSH model. This difference has been examined by simulating Hurricane Rita (2005) in both CEST and SLOSH along the Louisiana coastline. The comparison of computed storm surges with field measurements indicated that SLOSH overestimated the magnitude and extent of overland flooding in the near flat coastal areas, while CEST produced the pattern matching with the observations. The slip coefficient in the SLOSH model was adjusted and successfully generated an inland inundation envelope similar to CEST. The storm surge unit at NHC has adjusted the computation of overland flooding on the new Huston basin based on this finding and is examining this adjustment for other locations.