Analysis of observational characteristics of supercell tornadoes in eastern Hubei on 6 July 2026

On 6 July 2026, under the combined influence of a typhoon and a northeast cold vortex, three tornadoes occurred in eastern Hubei, two reaching EF3 and one EF1, causing severe casualties and property damage. Based on field disaster survey data, hourly ERA5 reanalysis data, regional meteorological observing stations and dual-polarization Doppler radar data, this paper analyzes synoptic background, environmental conditions and radar characteristics of the two EF3 tornadoes that affected Xianning and Ezhou in eastern Hubei. The results show that the tornadoes occurred near a northeast–southwest-oriented typhoon inverted trough, in an environment favorable for supercell tornadoes, with MUCAPE>2000 J·kg⁻¹, PWAT>60 mm, SRH3>200 m²·s⁻², a low LCL and strong vertical wind shear. The two EF3 tornadoes originated from the same northeastward-moving supercell, which possessed a deep and persistent mesocyclone and a vertically tilted structure; the tornadoes occurred at the top of the hook echo, accompanied by mesocyclone contraction, cyclonic vortex intensification and a rise-then-fall of the mesocyclone top. TVS and TDS were detected for both tornadoes. The maximum TVS shear increased rapidly and the height of the maximum shear decreased when tornadoes occurred. Low CC and low ZDR at the TVS position were found, consistent with the TDS features of high reflectivity factor, low ZDR and abnormally low CC. These results indicate that the rapid increase in maximum TVS shear and the decrease in the height of the maximum shear can serve as a key nowcasting signal for strong tornadoes, providing a lead time of about 7 min for the Xianning tornado; CC dropping below 0.8 can be used as a criterion for tornado touchdown confirmation and warning.