The Cape Canaveral Sea and River Breezes: Kinematic Structure and Convective Initiation

Abstract

This study examines complex flow patterns associated with the Cape Canaveral sea breeze and sea-breeze front using dual-Doppler radar, sounding, and surface data collected on 26 July 1991 during the Convection and Precipitation/Electrification Experiment. This case focuses on (a) the structure of the sea breeze, an associated trailing convergence line, river-induced convergence zones, and thunderstorm outflow boundaries, and (b) the development of convection where these features interacted. Variations in the direction of the sea breeze in the vicinity of irregular coastlines, such as Cape Canaveral, can lead to persistent zones of convergence within the sea-breeze air. The findings show that these zones of convergence, in turn, can locally increase the depth of the sea-breeze air and create circulations at the top of the sea breeze, which can support the development of convection. The observational study is the first to document the development and evolution of the trailing convergence line over Cape Canaveral and show that its presence can be instrumental in thunderstorm initiation. Small inland water bodies, such as the Indian River, can have a strong influence on the location where thunderstorms first develop as the sea breeze propagates inland. Divergence over the small, relatively cooler Indian River during daytime was sufficient to maintain a quasi-stationary convergence zone that, when approached and disrupted by the sea-breeze front, triggered thunderstorms. The intersection point between the sea-breeze front and the river-induced convergence zone identified the location where successive thunderstorms developed during the day.