Application of Multi-Source High Frequency Detection Data to the Nowcast Local Severe Convection in Beijing
Article
Figures
Metrics
Preview PDF
Reference
Related
Cited by
Materials
Abstract:
This study comprehensively applied multi-source high-frequency observational data to analyze the genesis, development, and applicability in nowcasting and warning of a localized severe convective event that occurred in Beijing on August 27, 2020. Utilizing various high-frequency detection instruments including microwave radiometers, wind profile radars, S-band Doppler radars, X-band dual-polarization radars, and a three-dimensional lightning positioning system, the evolutionary characteristics and warning indicators during thunderstorm initiation, development, and dissipation stages were investigated. The results demonstrated: 1) Microwave radiometer-retrieved temperature, humidity, and stability parameters (K-index, SI-index) showed significant variations 30-120 minutes prior to the convective outbreak, effectively indicating energy accumulation. 2) Enhanced vertical wind shear and low-level warm advection detected by wind profile radars provided 55-120 minute lead time in reflecting dynamic lifting conditions. 3) S/X-band radar observations of echo overhang structures, centroid height variations, and dual-polarization parameters (ZDR, KDP) enabled identification of hail growth regions, achieving 12-37 minutes lead time for hail and severe wind warnings. 4) Lightning jump signals (2σ algorithm) exhibited strong correlation with severe weather (hail and winds), with the first jump providing 52-minute warning lead time for hail. Validation with four other 2020 convective cases confirmed that synergistic application of multi-source observations can overcome limitations of single-instrument detection, enabling dynamic tracking of environmental energy, storm structure, and lightning activities, thereby providing valuable references for short-term forecasting.