One of the shortcomings of at least those lee-wave theories which are mathematically tractable with relative ease, is that they do not satisfy the perturbation energy equation. In this report we started from a simplified energy equation and by parameterizing certain terms using plausible assumptions, we arrived at a solution of the primitive equations for internal gravity waves. Several cases of lee waves near Boulder were compared with this solution and results are encouraging. The proposed internal gravity wave solution suggests that wave formations observed in the noctilucent cloud region are most likely generatedin situ and not propagated upward from the troposphere.