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 10:05 pm. Next forecast at approx. 10:05 pm.Get WillyWeather+ to remove ads