Wind Profiler Radar Analysis of an Extremely Short Time Strong Precipitation Process under Weak Weather Background

Based on the observation data of wind profiler radar, Doppler weather radar and minute-level automatic weather station, the evolution characteristics of horizontal wind, vertical velocity, atmospheric refractive index structure constant, low-level jet index and vertical wind shear during an extreme short-term heavy rainfall process in Chengdu on August 3,2022 were analyzed, and the application of wind profiler radar to short-term heavy rainfall weather was discussed. The results show that: (1) The extreme short-term strong precipitation is a warm cloud precipitation with high precipitation efficiency triggered by the low-level easterly pulsation under the weak weather background and good local water vapor conditions. (2) The wind profiler radar network data can capture the small and medium-sized changes in the atmospheric circulation, which has a good short-term and imminent forecast significance for the occurrence and falling area of this short-term heavy precipitation. (3) The change of wind field measured by wind profiler radar is earlier than that of precipitation, which has a good indication for precipitation forecast. (4) The vertical velocity and atmospheric refractive index structure constant can well reflect the occurrence and the end of precipitation. (5) The low-level jet index and vertical wind shear increase significantly 40 minutes in advance before precipitation.