The National Weather Service is warning ocean­goers to be aware of continued high surf as an elevated northwest swell is expected to gradually decline through Monday.

A high-surf advisory is in effect for the north and west shores of Niihau and Kauai; the north shores of Oahu, Molokai and Maui; and the east shores of Kauai, Oahu, Molokai, Maui and Hawaii island through 6 a.m. Monday.

Forecasters predict waves of 10 to 15 feet along north shores and 6 to 12 feet along west shores.

Surf conditions could result in strong breaking waves, shore break, and strong longshore and rip currents.

Meanwhile, a high-pressure system north of the state is expected to sustain tradewinds for the next several days. Forecasters say clouds and passing showers will favor windward and mauka areas, with a few brief showers over some leeward locations.

South shore waves are also expected to get a small boost today, but waves will not reach advisory levels. Wave faces are expected to be 2- to 4-feet.