A high surf advisory for the south-facing shores of all Hawaiian isles has been extended through Friday evening due to a new reinforcing swell that is expected to fill in through the day.

Weather officials said surf is expected to reach heights of 5 to 8 feet today, and rise to 8 to 12 feet tonight through Friday.

An advisory issued earlier this week was due to a long-period, south swell generated by a powerful storm in the southern hemisphere that declined Monday through Tuesday night. A reinforcing south swell arrived Wednesday.

Expect strong breaking waves, shore break, and rip currents, making swimming difficult and dangerous. Beachgoers, swimmers, and surfers should exercise caution and heed all advice given by ocean safety officials.

Forecasters expect trade winds to continue for the next few days, with showers focused over the windward and mauka areas. But trades are expected to weaken late Thursday and Friday before increasing again this weekend.