The National Weather Service has issued a flash flood watch for Kauai and Niihau that began at midnight today and will be in effect through Sunday because of a slow-moving weather system that poses a "substantial chance of flooding rain."
On Friday, high surf forced the closure of some beaches on Kauai, and the Weather Service extended the high-surf advisory for north- and west-facing shores for much of the state until 6 a.m. today.
The Weather Service on Friday also advised residents in areas prone to flooding to begin preparations.
"Anyone planning outdoor activities over the holiday weekend, including hikers and campers, should pay close attention to the latest forecasts and have a reliable and immediate way to get weather warnings," forecasters said.
The storm is expected to affect mostly Kauai County but could have a significant effect on Oahu if it shifts slightly east, a forecaster said.
In addition to scattered showers and the possibility of thunderstorms, the weekend forecast for Honolulu calls for Kona winds bringing humid conditions and volcanic haze.
Forecasters said moisture from the front may linger into Monday, but cooler northeast tradewinds should begin returning Tuesday.
On Kauai, county officials at the Ocean Safety Bureau closed all beaches north of the Hanalei pavilion from Hanalei to Kee on Friday.
Kauai County officials reported dangerous ocean conditions on Kauai’s North Shore, with strong rip currents and waves with 15- to 25-foot faces.
Honolulu fire officials reported coming to the aid of a boogie-boarder at Waimea Bay just after 7:30 a.m. and a swimmer at Turtle Bay at about 11:30 a.m. Capt. James Todd, Honolulu Fire Department spokesman, said the boogie-boarder needed help getting back to the beach.
Capt. John Hoogsteden, North Shore Ocean Safety official, described Friday’s surfing conditions along Oahu’s North Shore as "very good." Along with the Vans Triple Crown of Surfing competition at Sunset Beach, North Shore beaches were extremely busy, said ocean safety and fire officials.