Meteorological Observations of a Funnel Cloud at Zhuhai, China, on 8 May 2026 and the Forecasting of the Associated Mesocyclone

A funnel cloud is a rotating column of air that extends from the cloud base towards the ground yet does not touch the ground. It can be the precursor to a tornado or waterspout. The associated high winds can be destructive. This paper analyzed the meteorological observations for a funnel cloud spotted at Zhuhai in the afternoon of 8 May 2026, and performed simulation of its associated mesocyclone to study the formation mechanism of the funnel cloud. The funnel cloud was found to occur within a surface trough of low pressure under moderately unstable atmospheric conditions; winds were generally weak in the atmospheric boundary layer and the middle troposphere was wavy. The vorticity in the atmospheric boundary layer was lifted by the upward motion associated with the mid-tropospheric waves and daytime heating to form a funnel cloud; such a mechanism is supported by observations and model simulations. The weather radar generally captured the shallow convection and the radar-analyzed wind field depicted significant updraft in the reflectivity core associated with the mesocyclone. On the simulation side, the atmosphere–ocean–wave coupled model with radar data assimilation captured the isolated cyclonic feature near Zhuhai and the upward motion of the air column. Apart from the formation mechanism, this paper documented this rare event as a step forward in building up the climatology for the atmospheric conditions favourable for funnel cloud formation in the region.