A powerful south swell with waves as tall as 7 to 8 feet will slam the San Diego County coastline this week, generating potentially life-threatening rip currents, the National Weather Service says.

The “highest surf will be at south-facing beaches and peak Tuesday and Wednesday,” the weather service said in a statement. “(The) swell and surf will slowly subside beginning Thursday with a shorter period, but will remain elevated into Friday.”

The weather service says that anyone caught in a rip current should yell for help and try to remain calm so that they don’t exhaust themselves while waiting for help. If possible, a person should swim parallel to shore until they exit the area where the rip currents are hitting hardest, then swim for shore.