Formulation of a Rip Current Predictive Index Using Rescue Data

Lifeguard rescue logs from Daytona Beach, Florida were examined in an effort to correlate rip current-related rescues with concurrent wave and wind measurements on a barred shoreline with periodically spaced rip channels. The frequency of rip current rescues increased markedly during (1) shore-normal wave incidence and (2) mid-low tidal stages. The National Weather Service’s present rip current forecasting technique was modified to include wave direction and tidal stage as predictive parameters. The inclusion of these new parameters and the elimination of two wind parameters resulted in more accurate forecasting of days with a high number of rip current rescues.