UPDATE: National Weather Service issues flood watch; cancels high surf advisory
Update 4:00 p.m. Sunday: The National Weather Service has canceled the high surf advisory for Kauaʻi, with buoys showing swell heights out of the northeast have dropped Sunday afternoon. But the National Weather Service has issued a new alert flood watch for all Hawaiian Islands through 6 p.m. Monday.
A surface trough will develop west of the islands, allowing deep moisture to move over the islands from the south. While rainfall may be light at first, heavier slow-moving showers
are expected to develop, bringing the potential for flash flooding.
Flash flooding is life-threatening. Do not cross fast-flowing water in your vehicle or on foot.
Original post: The National Weather Service said a high surf advisory for north- and east-facing shores of Kauaʻi, Niʻihau, Oʻahu, Molokaʻi and Maui will be in place through Monday morning.
A large north-northeast (010-040 degrees) swell will continue to produce elevated, rough surf along most north- and east-facing shores of the smaller islands. In addition, the north- and west-facing shores of the Big Island will have elevated surf. This north-northeast swell will gradually lower later Sunday night.
The forecast is for large breaking waves of 18 to 22 feet along north-facing shores, and waves of 8 to 12 feet along east-facing shores. Waves up to 11 feet are forecast along west-facing shores of the Big Island.
Strong breaking waves and strong currents will make swimming dangerous. Head all advice from ocean safety officials. When in doubt, don’t go out.