A high-surf warning is in effect for Hawaii’s north and west facing shores as dangerously large waves and hazardous conditions are expected through today.

The National Weather Serv­ice in Honolulu has issued the warning for the north and west shores of Niihau, Kauai, Oahu, and Molokai; north shores of Maui; and west shores of Hawaii island. The warning is in effect until 6 p.m. today as a west-northwest swell brings dangerously large waves.

Surf was expected to peak Thursday night, then begin to ease today as the swell fades into the weekend.

Forecasters said waves of 30 to 40 feet along north shores Thursday were expected to drop to 20 to 30 feet today, while surf of 20 to 30 along west shores will drop to 18 to 24 feet today. Surf of 10 to 14 feet is expected on the west shores of the Big Island.

The large surf will create strong breaking waves, powerful currents and hazardous conditions at harbor entrances and channels, weather officials said. Residents and visitors are advised to stay away from affected coastlines and prepare for potential road closures and coastal flooding.

A small-craft advisory is also in effect until 6 p.m. today for waters around the islands, with seas building to 10 to 15 feet. Mariners, especially those with smaller vessels, should avoid navigating in these dangerous conditions, officials said.

While weather across the islands is expected to remain stable for now, a cold front and upper-level disturbance this weekend could bring increased tradewind showers, especially during the early-morning hours along windward and mauka areas, the weather service said.