The method to account for turbulent refractivity fluctuations for split-step parabolic equation Fourier method are presented. The results of microwave propagation simulations in an evaporation duct with account for scattering by correlated turbulent fluctuations of the tropospheric refractivity index is analyzed. It is shown that refractivity fluctuations leads to energy leakage from the duct and as result there are additional attenuation inside the duct. There is also shown that fluctuations of the received power above the duct significantly higher compared with the variations inside the duct.