A high surf warning is in effect this weekend for the south shores of all Hawaiian islands as a “historic” south swell from the South Pacific reaches the state.

State officials said several beach parks will be closed due to the dangerous conditions.

The National Weather Service said the surf warning is in effect from 6 a.m. Saturday to 6 a.m. Monday.

Surf will build to 14 to 18 feet during the day on Saturday and rise to 18 to 24 feet Saturday night through Sunday night.

The “historic” south swell — the largest in years, NWS officials said — will produce dangerous waves before slowly decreasing through the first half of next week.

The weather service said to expect ocean water “occasionally sweeping across portions of beaches, very strong breaking waves, and strong longshore and rip currents.” The waves and currents may impact harbor entrances and channels, which can cause challenging boating conditions.

“The large, breaking surf, significant shore break, and dangerous currents make entering the water very dangerous,” the NWS said.

Boaters should also be aware of an increased number of surfers and those on body boards using a harbor channel to access surfing areas.

Surf along eastern shores will also remain elevated and rough into early next week. Swells from weakening Tropical Storm Darby are expected to amplify conditions and will likely peak on Saturday. This swell will mainly impact the eastern shores of Hawaii island, which are under a high surf advisory Saturday, the NWS said.

The Hawaii Department of Land and Natural Resources’ Division of State Parks will be closing the following beach parks Saturday and possibly Sunday: Hapuna State Recreation Area, Kua Bay, and Kekaha Kai on Hawaii island. In addition, they said:

>> On Oahu, Kaiwi State Scenic Shoreline on the Makapuu Point Lighthouse trail is an area of concern. “The tide pools remain closed,” DLNR said. “Ignoring this closure may be extremely hazardous due to the anticipated high surf.” Also, the Keawa’ula section of Ka’ena Point State Park may be closed.

>> On Maui, Makena State Park will be open on Saturday but may close on Sunday.

Large wave run up and coastal impacts are expected, especially during the late afternoon high, DLNR officials said.