This paper presents a numerical study of strong shock wave diffraction at a convex edge, using an explicit second‐order Godunov‐type Euler scheme based upon the solution of a generalized Riemann problem (GRP). For large diffraction angles the Euler computations produce flow separation at the diffraction edge, without artificial forcing, similar to experimental findings, and salient flow features such as primary and secondary shock waves, contact surfaces and vortex trajectories are well predicted. At smaller diffraction angles the Euler computations show that separation occurs further downstream of the edge than is found experimentally. The preliminary formulation of Navier‐Stokes modelling for this case is considered.