Cool temperatures and high surf remain in the forecast for most Hawaiian Islands as a high wind warning remains in effect for the snow-dusted peaks of the Big Isle.

The National Weather Service in Honolulu has posted a high surf advisory for the north- and west-facing shores of Niihau, Kauai, Oahu and Molokai and the northern shores of Maui, effective until 6 a.m. Thursday.

Forecasters say surf is expected to rise to 18 to 24 feet late this afternoon into tonight along the north- and west-facing shores of Niihau and Kauai and northern shores of Oahu, Molokai, and Maui. Surf is expected to rise to 12 to 18 feet late this afternoon into tonight along western shores of Oahu and Molokai.

In addition to strong, breaking waves, strong rip currents will make swimming difficult and dangerous, officials said. Beachgoers, swimmers and surfers should exercise caution and heed all advice given by ocean safety officials.

Forecasters, meanwhile, say lingering moisture associated with an old weather front will keep unsettled weather in place across Maui and the Big Island this morning, with conditions improving from west to east this afternoon.

A flash flood watch has been issued for the Big Island, which could experience locally heavy showers and thunderstorms today, effective through this afternoon.

Cool and breezy northerly winds are expected elsewhere, which will focus showers mainly over windward slopes and coasts. The winds continue tonight, then ease through the remainder of the work week. But another cold front is expected over the weekend, keeping conditions cool.

Overnight temperatures are expected to dip as low as 49 degrees in parts of Kauai, and range from the low 50s to mid-60s on most of Oahu.

The old front keeps winter weather advisory in effect for the summits of Mauna Kea and Mauna Loa through noon today, with less than an inch of new snow, and less than a tenth of an inch of new ice possible above the 12,000-foot elevation.

A high wind warning remains in effect for Big Island summits until 6 p.m. this evening, with west winds of 55 to 65 miles per hour, and localized gusts over 80 miles per hour. Motorists are urged to drive with extreme caution, weather service officials said. Hiking activities should be delayed until winds subside.