A rising north-northwest swell appears likely to generate 20- to 25-foot waves along north shores and 15- to 20-foot waves on east shores Tuesday into Wednesday.

The National Weather Service issued a high surf warning until 6 p.m. Wednesday for north and west facing shores of Oahu, Kauai County, Molokai, and Maui.

“The event should peak overnight Tuesday night at extra-large levels, meaning high enough for breakers on select outer reefs. The full moon high tide of 2.4 feet, one of the astronomically higher tide levels of the year, should see the maximum in the coastal wave run-up in the wee hours early Wednesday pre-dawn,” forecasters said.

The swell is expected to gradually rise overnight and peak Tuesday afternoon into the evening.

“Expect ocean water occasionally sweeping across portions of beaches, very strong breaking waves and strong longshore and rip currents,” forecasters warned. “Anyone entering the water could face significant injury or death.”