In this study, the Penn State/NCAR mesoscale modeling system is used to evaluate the impact of the observations carried out during the California Land-Falling Jets Experiment (CALJET) on numerical model prediction of land-falling storms. Effort is focused on the mesoscale aspects of the prediction. We will present results of adjoint sensitivity analyses and data assimilation experiments for a CALJET IOP case. Detailed verification of the model prediction with observations will be carried out to reveal to what degree the model prediction of land-falling storms is affected by the in situ off-shore observations