Strong rip currents and high surf predicted for San Diego beaches over the July 4th weekend are prompting lifeguards to warn swimmers and offer tips on how to stay safe.

Over the July 4, 2013 holiday weekend San Diego lifeguards rescued 423 people, according to San Diego 6 News. For 2014 the National Weather Service has predicted “strong rip currents and high surf along south-facing beaches through Monday evening.”

The San Diego Lifeguard Services website lists information on rip currents, how to avoid them, and how to survive them. The site suggests swimmers ask the closest lifeguard where to swim, not to go out further than where you can touch the bottom, and to swim near and obey lifeguard instructions.

For those caught in a rip current, lifeguard instructions include relax, swim parallel to the shore, and wave arms toward a lifeguard for help.

6 News notes the July 4 weekend to be one of the busiest of the year at beaches and Mission Bay Park.