We propose a way of accounting for the lack of detailed knowledge about material shapes in computational time-domain electromagnetics. We use Legendre-Gauss-Lobatto, Stroud-2 and Stroud-3 quadrature formulas to solve the resulting stochastic equation and we show the efficiency of the proposed method over statistical Monte Carlo simulations. We also show how the radar cross section (RCS) in scattering is affected by the uncertainty in shape of the objects and by the direction of the incident field.