Abstract: Based on the data from the surface automated stations, the digital Doppler weather radar, and the WRFV2.2.1 model simulation, the interaction between the mesoscale gravity wave and the basic flow in the troposphere is studied, and the role of the waves in the severe snowfall and high surface winds is also investigated.It is shown by the radar data, the mean horizontal wind velocity in the 4.5-8 km layer of the troposphere tended to be uniform because of the momentum exchange between the wave motion and the basic current. At the same time, a saturated moisture jet stream was established extending almost throughout the troposphere as seen in the simulation, with the most severe precipitation area located just ahead of the 850 hPa jet center. Waves inspired under the exit region of an upper layer jet stream near the tropopause propagate downwards, resulting in an alternative acceleration or deceleration of the horizontal wind velocity in vertical over the station. The divergence or confluence caused by the wind change with the height has a substantial effect on the base reflectivity, and the radar echoes show the gravity wave signature. It is found that considerable increase in the intensity of the echoes occurred in the layers with the accelerating flow, but decreased in the layers with the decelerating flow, with about 40 km wide weak precipitation band imbedded in the major cloud bands, in a northwest-southeast orientation. While the waves propagate downwards, it was observed that, the gusty surface northeasterly wind appeared as the surface pressure drops rapidly, with an obvious change in the wind direction, and the intensity of the echoes begins to be weakened; the minimum reflectivity occurred just after the ridge passage. Observations from the radar show, the wind velocities beyond the boundary layer of the wind shear have the similar values, suggesting that the vertical circulation should be formed in the layer where the waves jointed to the wind shear. These vertical circulation would be established by the updrafts and downdrafts due to the vertically propagating gravity waves, together with the airflows moving in the opposite direction beyond the shear layer boundary.The observed severe surface winds centers distributed in a southwest-northeast orientation as in the gravity wave signature similar to the features of the echoes. The surface winds should be accelerated significantly by the downdrafts of these vertical circulation.