Surf generated by three tropical cyclones in the North Pacific is arriving on west, north and east shores of most islands, with surf on east shores reaching dangerous heights.
A high surf warning for east shores of Kauai, Oahu, Molokai, Maui and the Big Island is in effect until 6 p.m. Thursday and may be extended as waves generated by slow-moving Hurricane Jimena arrive on east shores.
East shores can expect waves of 12 to 18 feet through Thursday.
“There are two different swells (from Hurricane Ignacio and Hurricane Jimena) coming in,” said Derek Wroe, a meteorologist with the Honolulu office of the National Weather Service.
Besides surf, forecasters expect muggy conditions with the chance of heavy afternoon rains, and possibly thunderstorms, to continue through the weekend.
As Ignacio, which reached hurricane status again Wednesday, moves to the northwest of the islands, waves created during its passage will shift from the northeast to the northwest. Forecasters are monitoring the surf, but for now, they do not expect the north shore waves to reach advisory levels.
Typhoon Kilo, in the West Pacific, is generating a small swell on west shores and a storm last week in the southern hemisphere is bringing waves to south shores.
Forecasters predict 10- to 13-foot surf on the North Shore of Oahu, declining to 6 to 9 feet on Thursday. South shores should see 4- to 6-foot waves, rising to 6 to 9 feet Thursday and west shores can expect 2- to 4-foot wave faces, rising to 5- to 7-feet Thursday.
At 11 p.m. Wednesday, Ignacio was about 505 miles north of Honolulu, while Jimena was about 950 miles east of Honolulu.
Ignacio was moving northwest at 14 mph with sustained winds of 75 mph. Forecasters expect Ignacio to turn to the north-northwest and slow down as it moves away from the islands.
Jimena was still a category 2 hurricane with 110 mph winds Wednesday night. Hurricane-force winds extend 60 miles from the center and tropical storm-force winds go out to 185 miles from the center.
Jimena was moving northwest at 3 mph and is expected to take a sharp turn to the north over the next 24 hours that should keep it well away from the state.
Surf generated by Jimena will likely persist on east shores through the weekend, forecasters said.
“Jimena is very slow moving and it’s going to sit out there for a long time,” Wroe said.
Moist tropical air brought over the islands by Ignacio will continue to create hot and muggy conditions over the state through the weekend.
Jimena is still too far away to know exactly how it will affect Hawaii’s weather, but it appears likely that the storm will continue to block or weaken the tradewinds, extending the hot and humid weather over the state, Wroe said.
“There’s a very good chance that this humid weather will continue,” he said. “We could see light trades, and any trades will be nice but we haven’t been thinking that the trades will come back strong. … Unfortunately there’s no relief in sight.”
Afternoon showers, some of them heavy, are also in the forecast for the rest of the week.
The surf and heavy rains created problems Tuesday.
Waves washed sand and ocean debris over Kamehameha Highway near Kaaawa Elementary School on Oahu Tuesday morning..
Lifeguards on Oahu also helped 105 people to shore and used personal watercraft to assist another 125 people.
Lightning struck a house in Puna on Hawaii island Tuesday afternoon, but no one was injured and damage was not serious.
The surf also closed beach parks Coconut Island, Onekahakaha, Kealoha and the Bayfront canoe area and Bayfront Highway in Hilo between Pauahi Street and Waianuenue Avenue Tuesday.
On Kauai, east-facing beaches, from Anahola to Lydgate beach parks, remained closed Wednesday because of high surf and hazardous ocean conditions. Swimming is allowed at Poipu Beach, except for Nukumoi Point, where a dangerous rip current has formed.
On Hawaii island, Kealoha Beach Park in Keaukaha remained closed Wednesday because of debris and dangerous surf conditions, Hawaii County Civil Defense reported.
The weather service said the high surf on east shores is creating hazardous shore break, waves and rip currents.
“These dangerous conditions mean that only highly-experienced persons should enter the water. Inexperienced persons should remain off beaches and adjacent beachfront areas. Large breaking surf, significant shore break, and dangerous currents make entering the water very hazardous. Anyone entering the water could face significant injury or death,” forecasters said.
Star-Advertiser reporters Gary Kubota and Gregg K. Kakesako contributed to this story.