Aiming at the problems that the existing evaluation methods of the Shenyang vertical observation system are imperfect and mostly rely on single-equipment data, and the insufficient exploration of the synergistic application value of multi-source vertical observation data in the monitoring and early warning of severe convective weather under cold vortex conditions. This study intends to establish a multi-element data quality evaluation system suitable for the cold vortex circulation background. Meanwhile, it explores the monitoring performance of multi-device collaborative observations during cold-vortex severe convective rainstorms, so as to further enhance the regional three-dimensional vertical monitoring and nowcasting capabilities for cold vortex weather. Based on the observation data from the Shenyang Ground-based Remote Sensing Vertical Observation Comprehensive Station, this paper takes the extremely heavy regional rainstorm process in Liaoning from July 23 to 28, 2024 as an example, combines radiosonde observation data, establishes a multi-element data quality evaluation system for vertical observation suitable for the cold vortex background, and carries out systematic evaluation and application analysis. The results show that: (1) The operational availability of all five types of equipment in the vertical observation system reaches 100%, and the data quality meets the requirements of operational application and analysis; (2) Multi-element fusion analysis reveals that affected by the Northeast cold vortex, water vapor transport from the periphery of Typhoon Gaemi, and the subtropical high, the rapid accumulation of water vapor and the vigorous vertical development of cloud systems, combined with vertical temperature difference, low-level convergence and upward movement, as well as mid-level jet momentum transport, jointly trigger the severe convection process; (3) In terms of forecast and early warning, the wind profile radar can indicate changes in dynamic conditions 6-12 hours in advance; the microwave radiometer combined with GNSS/MET observation can capture water vapor and precursor signals 1.5 hours in advance; the millimeter-wave cloud radar can monitor the imminent development characteristics of convection 30-60 minutes in advance. The study shows that the established multi-element quality evaluation system can effectively support the data quality evaluation and application analysis of the vertical observation system under the cold vortex background, and the multi-equipment collaborative observation shows significant advantages in the identification of dynamic triggers, tracking of water vapor evolution, and imminent early warning of severe convective weather, providing important technical support for the refined monitoring and short-term forecasting of severe convective weather in Liaoning.