UPDATE: High surf advisory canceled for south-facing shorelines of Kauaʻi, Niʻihau

Update at 9:56 a.m. Aug. 2, 2025: Surf fell below advisory levels early this morning along south-facing shorelines of Kauaʻi and Niʻihau, prompting forecasters at the National Weather Service in Honolulu to cancel the high surf advisory that previously had been extended through today.

Surf along those shorelines will continue to decline throughout today.

Meanwhile, a dry and locally windy trade wind flow — with east winds sustained at 15 to 30 mph and gusts up to 50 mph — combined with relative humidity levels falling to between 35% and 45% during the afternoon, plus the available of dry fuel sources, will continue to produce critical fire weather conditions through today in leeward portions of both islands.

Therefore, forecasters at the National Weather Service office in Honolulu extended until 6 p.m. the red flag warning in effect for western and southern portions of Kauaʻi and all of Niʻihau.

Update at 9:18 a.m. Aug. 1, 2025: A high surf advisory is in effect for all south-facing shores until 6 a.m. Saturday.

Surf is expected to hit 10 to 14 feet through this afternoon and is then predicted to lower to 8 to 12 feet this evening through tonight.

The National Weather Service reported that strong breaking waves and strong currents will make swimming dangerous. Proceed with caution and heed advice from ocean safety officials.

Original story at 7:54 a.m. July 31, 2025: A long-period south swell will build to advisory levels today, with forecasters expecting it to peak near warning levels.

The National Weather Service forecast office in Honolulu issued a high surf advisory in effect until 6 p.m. Aug. 1 for south-facing shores of Kauaʻi and Niʻihau in response to the building swell.

Surf will build to 10 to 14 feet by this afternoon along those shorelines of both islands, accompanied by strong breaking waves and strong currents that will make swimming dangerous.

The public is advised to heed all advice from ocean safety officials, and always remember: when in doubt, don’t go out.

National Weather Service forecaters in Honolulu said in their 3:56 a.m. area forecast discussion for the state today that long-period forerunners from the south swell event already began to show up at local nearshore buoys.

This swell will continue to build in throughout the island chain through this afternoon, peak late today through Friday and then slowly lower thereafter.

This first south swell event will be followed by another long-period south swell early next week, so the high surf advisory might need to be extended or even upgraded depending on buoy observations toward this swell’s peak.

Get the latest weather forecasts and information about any advisories, watches or warnings in effect for your community at the National Weather Service website.