The Hazardous Convective Storm Monitoring of Phased-array Antenna Radar at Daxing International Airport of Beijing

The C-band phased-array antenna Doppler weather radar (C-PAR) with advanced working parameters can effectively monitor the hazardous aviation weather such as convective storm. To evaluate the performance of C-PAR, observations of two thunderstorm events in June of 2020 by the C-PAR and a S-band Doppler weather radar (CINRAD-SA) owned by Beijing Meteorological Bureau are compared and analyzed. In the morning of 18 June 2020, the weak echo of boundary outflow from thunderstorm is clearly detected by C-PAR, but CINRAD-SA cannot detect the weak echo until a new cell is triggered and enhanced by the boundary outflow, 24 minutes after first detection by C-PAR. A severe hailstorm is observed by C-PAR and CINRAD-SA, and the vortex signature of radial velocity is clearly observed by C-PAR, but not clearly by CINRAD-SA. The storm morphology and suspended echo due to updraft captured by C-PAR is well consistent with the thunderstorm conceptual model, but the storm vertical structure captured by CINRAD-SA is not so typical. The spatial variation of the intensity is very fine and with rich texture on the echo of C-PAR, but it is vague and coarse on that of CINRAD-SA. The three-body scattering spike and side-lobe echo of the hailstorm is easy to be captured by C-PAR, but it is hard to be recognized by CINRAD-SA. At the same time, the phased array radar uses pulse compression technology to obtain better weak echo detection capabilities. The differences of echo distribution and evolution revealed by C-PAR and CINRAD-SA verified that the C-PAR has advantages not only on temporal and spatial resolutions, but also on space coverage and sensitivity to weak echo. For small-scale weather systems like hailstorm, downburst and thunderstorm boundary outflow, the lifespan varies from tens of seconds to minutes, making it difficult to be captured by conventional radar. Therefore, as terminal weather radar, the C-PAR is more suitable to monitor small and medium-scale hazardous aviation weather. The C-PAR can capture the main structure characteristics of precipitation, reveal the initiation and development of a convective storm, and obtain better weak echo detection capabilities. With outstanding advantages, the C-PAR becomes an important and effective detection equipment for terminal aviation weather, which helps to improve aviation flight safety.