© 2019 The authors.The dynamic response of composite structures under impact loading conditions is a complex problem which is attracting substantial attention. The case of hailstone impacts introduces additional challenges. Hence, the main goal of this paper is to present recent work towards the development of a computationally efficient impact model that combines a novel phenomenological viscoplastic contact law with a new time domain spectral shear plate finite element including nonlinear effects due to large displacements and rotations. The new viscoplastic contact law, which provides the coupling between the hailstone impactor and the target composite plate, is derived from analytical expressions and observations based on experiments and numerical results. The proposed model simulations are compared with a 3-D continuum explicit FEA model and experimental results from high-velocity spherical hailstone impacts on woven glass/epoxy composite plates, which are conducted in our impact facility. The results demonstrate the efficiency and accuracy of the proposed model.