A uniform asymptotic physical optics (UAPO) solution is proposed in this work to determine the field diffracted by building edges in mobile radio environments. A Gaussian rough lossy surface model is applied for describing the wedge surfaces. The diffraction coefficients are obtained by using a physical optics (PO) approximation of the surface current densities induced by an incident electromagnetic field on the illuminated face and by performing a uniform asymptotic evaluation of the resulting radiation integral. The resulting analytical expression is given in terms of the transition function of the uniform theory of diffraction (UTD) and is easy to handle and to implement in a computer code.