A Convective Burst Event in Tropical Storm Ophelia (2005)

Numerical simulations have indicated that convective burst events precede tropical cyclone genesis. However, these convective burst events in tropical depressions have not been observed by airborne Doppler radars. Multiple legs of high-resolution airborne Doppler radar data were collected during Tropical Storm Ophelia's genesis phase by the NCAR ELDORA and NOAA P3 tail radars as part of the Hurricane Rainband and Intensity Experiment (RAINEX).

This convective burst event consists of several intensive convective cells with vertical velocities exceeding 40 m s-1 in the upper troposphere. Positive/negative vertical vorticity couplets are associated with these updraft cores. Two branches of inflow, one at low level and one at mid-level (~8 km), can be identified in the 3-D wind fields. Pressure and buoyancy retrievals reveal a low pressure and positive buoyancy within the updraft core. The kinematic and dynamic structures of this convective burst event from 5 legs of ELDORA data will be presented.