The Advanced Microwave Sounding Unit has a nadir resolution of 50 km increasing to 155x82 km at edge of scan. Modern numerical weather prediction models are or beginning to exceed this resolution. Ancillary databases, such as digital elevation maps are available with a resolution of a few meters. This paper presents a method of using the measured antenna pattern of the AMSU in conjunction with a digital elevation model to perform radiative transfer over coastlines and other inhomogeneous terrain.