WEATHER NOTE: AIRCRAFT OBSERVATIONS IN THE IMMEDIATE VICINITY OF TWO WATERSPOUTS

Abstract

Two waterspouts were observed aloft from a private aircraft recently near Lower Matecumbe Key, Florida. Color slides and zoom movies of both waterspout vortices on the sea surface and aloft were obtained. A detailed description of the equipment used and a discussion of the synoptic pattern of that day are presented. The data show some interesting details regarding the dynamics of the observed waterspout circulations. Both waterspouts traversed a similar path. A subsequent ground survey of the paths taken over the Key, together with damage reports and eyewitness accounts, indicate that the second waterspout was much more intense than the first. The authors plan to make detailed calculations, using the zoom movies, of a radial profile of the tangential and vertical wind speeds about the second waterspout vortex. Rates of forward motion and funnel diameter at various levels below the cloud base will also be obtained. An additional, more quantitative report of this interesting encounter will be forthcoming.