If you’re heading to the beach over the next couple days, watch out for some rough surf and “dangerous rip currents.”

The National Weather Service’s Boston office has put out warnings ahead of Friday and Saturday, especially at east-facing ocean beaches of Cape Cod and Nantucket.

Beachgoers are being urged to never swim alone in these rough conditions.

“Many area beaches do not have lifeguards post Labor Day Weekend which makes rip currents more dangerous,” reads the National Weather Service warning. “Best to find a beach with a lifeguard and never swim alone.

“If caught in a rip current, relax and float,” NWS added. “Don’t swim against the current. If able, swim in a direction following the shoreline. If unable to escape, face the shore and call or wave for help.”

Large breaking waves of 4 to 9 feet are expected in the surf zone.

“Inexperienced swimmers should remain out of the water due to dangerous surf conditions,” NWS posted.

A low pressure system moving north will spark the coastal impacts.