Using a recursive solution of the Yang-Mills equation, we calculate analytic expressions for the gluon fields created in ultra-relativistic heavy ion collisions at small times $tau$. We have worked out explicit solutions for the fields and the energy momentum tensor up to 4th order in an expansion in $tau$. We generalize the McLerran-Venugopalan model to allow for a systematic treatment of averaged charge densities $mu^2$ that vary as a function of transverse coordinates. This allows us to calculate radial, elliptic and directed flow of gluon fields. Our results can serve as initial conditions for hydrodynamic simulations of nuclear collisions that include initial flow.