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At a lidar sounding of atmosphere meteorological parameters, (wind velocity and direction profile) the precipitation more often is considered as a hindrance, which limits the distance and accuracy of the measurements and in some instances performs the impossible measurements. But in the course of investigations it has been found that in certain situations, the precipitation increase efficiency of lidar sounding. In this case the distance and accuracy of sounding are increased. Primarily this is true for precipitation, which has the intensity no more than 1.5 mm/h. Furthermore, the possibility of determinations of the microstucture and integral characteristics of precipitation area is existed. The investigations were performed using the correlation scanning three-path lidar with vertical scheme of sounding. In the course of measurements the spatial-temporal series reflected by precipitation optical signals were amassed. The handling of the lidar data was based on the correlation-spectral method. The study of the optical signals reflected from preciptiation showed that the increase of the wind velocity sounding efficiency is available by amplification of the signal fluctuation components. Limitations on the rain rate are caused by powerful rain. A maximum of the dropsize distribution function is displaced inside of the high quantities which are not carried by air flows and useful information for the estimation of wind velocity gives the raindrops with dimensions no more than 0.6 mm in diameter. As the lidar allows to make a vertical cut of the precipitation area, that it was seen the moving of forward and reverse fronts of the precipitation area at the spatial range of the optical signals. From a comparison of the front positions in different times the drop speed of the different rain group is determined. This allowed us to estimate the range size raindrops and raindrop size distribution function was determined. The knowledge of precipitation microstructure parameters allows obtained integral characteristics of precipitation area: rain rate (mm/h), watery (g/m3), raindrop concentration (1/m3).
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