The mixed convection flow and heat transfer characteristics in a two-dimensional plane, laminar offset jet issuing parallel to an isothermal flat plate have been investigated numerically. The unsteady form of the vorticity transport equation has been solved to obtain the steady-state solution. The isothermal heated plate is 30 times the jet width and the offset ratio is 1. The behavior of the jet in the range of Reynolds number Re = 300-600 and Grashof number Gr = 10(3)-10(7) is described in details. The medium considered is air (Pr = 0.71). It is found that the reattachment length is strongly dependent on both Re and Gr for the range considered. Simulations are made to show the effect of entrainment on the recirculation eddy. The variation of the local Nusselt number is presented for various Re and Gr. An empirical correlation of average Nusselt number as a function of Richardson number (Ri Gr/Re-2) and Re has been given. (C) 2008 Elsevier Ltd. All rights reserved.