The results of the tests reveal that the NMM dynamics can reproduce very well the observed atmospheric spectrum in both the -3 and -5/3 ranges provided there is a sufficiently strong energy source on the small scales and given enough time. Moreover, on the cloud resolving scales, the model successfully reproduced the -5/3 slope corresponding to decaying 3D turbulence. It is believed that the nonlinear energy cascade controlled by the conservation of energy and enstrophy played an important role in reproducing the observed spectral shape. Namely, another dynamics formulation that relied only on dissipation for controlling the nonlinear energy cascade had difficulties in reproducing the spectra. The possibility of employing the observed atmospheric spectra for validation of mesoscale models is discussed.