Gray Whale Cove State Beach (Devils Slide) UV IndexUnited StatesCASan Mateo CountyGray Whale Cove State Beach (Devils Slide)1-Day3-Day Graph Plots Open in Graphs UV Forecast NOAAGray Whale Cove State Beach (Devils Slide) UV forecast issued yesterday at 11:18 am. Next forecast at approx. 11:18 am. UV IndexGet WillyWeather+ to remove ads