ISSN 1000-0526
CN 11-2282/P
CN 11-2282/P
Damage Survey and Mesoscale Characteristics of the Tornadoes in Heze of Shandong Province on 5 July,2024.
- Article
- Figures
- Metrics
- Preview PDF
- Reference
- Related
- Cited by
- Materials
Abstract:
A documented tornado outbreak event occurred in Shandong province on 5 July,2024, influenced by the upper-level trough and Huang-Huai cyclone.The event notably impacted Heze City, where tornadoes are rarely reported, causing substantial casualties and property damage. This study analyzes the development and evolution of tornadoes in Dongming and Juancheng counties of Heze City, along with their environmental conditions and mesoscale characteristics, based on disaster investigations, online video and photo evidence, ERA5 reanalysis data, and dual-polarization radar observations. The main conclusions are as follows: according to the comprehensive assessment, the maximum intensity of the tornadoes in Dongming and Juancheng Counties reached peak intensities corresponding to strong tornado (equivalent to EF2-EF3 level),which located approximately 50 km northeast of the Huang-Huai cyclone center. The environment features conducive to the formation of supercell tornadoes included abundant water vapor, low lifting condensation level, sufficient convective instability energy, strong storm-relative helicity, and strong vertical wind shear. Meso-β-scale convergence line and appropriate cold pool intensity provided favorable conditions for the initiation, development of the tornadic storm, and the strengthening of near-surface vertical vorticity. Both tornadoes originated from the same southwest-northeast moving supercell, characterized by:(1)a robust echo centroid near 5 km altitude,(2)a persistent, deep mesocyclone with tilted vertical structure.The tornadoes appeared at the top of the hook echo of the supercell, and the period of tornado occurrence was accompanied by signals such as the reduction of mesocyclone scale and the enhancement of cyclonic vortex.The radar detected both tornado vortex signature(TVS) and tornado debris signature(TDS) for the two tornadoes, with the earliest detection of TVS being 15 minutes and 5 minutes ahead of the tornado occurrence time,respectively.During the occurrence of tornado, the correlation coefficient corresponding to the vortex features rapidly decreases. The lowest value (0.46) appears at the time when ground damage is most severe, which may be attributed to the mixing of hydrometeor particles and a large amount of debris carried by the strong updraft, as well as the reduction in signal-to-noise ratio caused by the intense updraft. After the tornado dissipated, the low CC value characteristic persisted for more than 15 minutes. These findings enhance understanding of Huang-Huai cyclone-associated tornadoes and provide operational guidance for tornado monitoring and warning systems.
Keywords:
Project Supported:
Clc Number:
Mobile website
