The Ocean Beach Pier was closed Friday morning by San Diego Lifeguards to prevent damage by expected high surf.
Ocean conditions will be monitored and the pier may be reopened on Saturday, the San Diego Fire-Rescue Department posted on social media.
The pier has been closed several times in the last few years for renovations and damage, and as a precaution amid high surf. in January, the pier was closed for six months due to winter storm damage. It was finally reopened to the public on July 1, just in time for the Fourth of July holiday weekend and one day ahead of the 57th anniversary of the pier's grand opening.
The National Weather Service said a swell of 4 to 5 feet with a period of 17 to 20 seconds from the west-northwest could generate large surf and strong rip currents through Friday.
Get top local stories in San Diego delivered to you every morning. Sign up for NBC San Diego's News Headlines newsletter.
Foam may be highest on exposed west-facing beaches of San Diego County, where sets of up to 9 feet were expected to produce the greatest threats, the NWS said.
Swell and surf should begin to lower Friday night and Saturday, forecasters said.
A high surf advisory was in effect for San Diego County through 9 p.m. Friday.