Furthermore, preliminary results from a more quantitative analysis will also be discussed. The TB's obtained from a four-stream radiative transfer model (RTM), which takes as input, numerical weather prediction (NWP) model variables such as pressure, temperature, and moisture, will be compared to SSM/I TB's. The feasibility of using SSM/I TB's directly for storm initialization will be discussed. An adjoint of the RTM is developed, and a sensitivity analysis is performed. The goal of this study is to test the potential application of SSM/I TB's for hurricane initialization, therefore improving the quality of the forecast of Hurricane Bonnie.