Using a fine resolution numerical model (40002 ×2 grid-points) of the two-layer shallow-water equations of the mid-latitude -plane dynamics, it is shown that there is no sudden breakdown of balance in the turbulent enstrophy cascade but a faint and continuous emission of inertia-gravity waves. The wave energy accumulates in the equator-ward region of the domain due to the Coriolis parameter depending on the latitude and dispersion relation of inertia-gravity waves.