A thunderstorm pounded parts of O'ahu yesterday, causing a repeat of flooding on the already-saturated Windward side but also hitting 'Ewa Beach and the North Shore.

A flash-flood watch was posted for 6 a.m. today and through this evening. The weather should ease up early this week, but showers and thunderstorms could return Wednesday night and continue through the weekend, said Victor Proton, a National Weather Service forecaster.

Lightning struck electrical transformers in 'Ewa Beach, Wahiawa and Kailua yesterday, causing power outages to small pockets of homes.

The townbound lanes of Likelike Highway will be closed from 9 a.m. to 3 p.m. today while crews remove loose rocks over the Wilson Tunnel, state Transportation Director Rod Haraga said.

High water yesterday prompted officials to close roads in Sunset Beach and Waikane, while homes along the Windward Coast and in 'Ewa Beach reported varying degrees of flooding.

Some residents of normally dry 'Ewa Beach awoke to find their streets and homes flooded. Water rose as high as 4 feet, inundating cars.

On Laukona Loop, just off Papipi Road, storm drains clogged with debris, cement and auto parts caused water to rise, flooding the living rooms of about five homes. At least three cars there were submerged to the roof, and another car was totaled when it hit submerged debris while being driven on Laukona Loop.

Residents on Kuhina and Ahuna streets also reported house flooding, police said.

Kristie Cruz, a 24-year-old salesclerk, said she woke up at 7 a.m. to heavy rain and began stacking towels near the front door of her boyfriend's family's home on Laukona Loop.

"We had to move our cars; the water was up to our knees (in the garage)," she said as she stood near her front door. "We're worried it is going to come into the house."

"This is what happens when everybody throws their opala in the drain. It backs up," said Ama Kahalewai, a 34-year-old heavy equipment operator who lives on Laukona Loop.

Augie Avila, 26, said he and a friend had to push a gray Honda Civic out of the water because it had flooded up to the top of the driver's seat. Under the hood was "bust up" and he said he will have to replace the car's electronic system and possibly the engine.

"We have to replace everything," he said, shaking his head. "Lake Laukona."

The Fire Department responded to 19 calls for assistance from residents between 8:55 a.m. and 12:30 p.m., when the rain was heaviest, Capt. Sigmund Oka said. Nine of the calls were to homes in Windward O'ahu, six in 'Ewa, two in 'Aiea, one in Kalihi and one in Salt Lake.

The rains chased a group of about 70 people camping at Kakela Beach Park in Hau'ula to a Red Cross shelter at Brigham Young University-Hawai'i in La'ie. The group of children and parents from the Kalihi Valley Athletic League had awoken early yesterday morning to heavy rains that filled their tents.

"We were all sleeping when (rain) ... started pouring in the tents," said Mao Prescott, 15. "Tents went flying."

The students were taken to the Hau'ula Shopping Center, said Tiare Faatea, a group leader. Because of road closures, school buses couldn't make it through to pick up the group. The campers stayed at the Red Cross shelter at BYUH for about three hours before a school bus picked them up to take them back to Kalihi.

In Ka'a'awa, Carol Kaufman feared her home could flood again like it did two weeks ago during the heavy rains. Even with sandbags barricading three doors of her home, water still seeped into the back room.

Kaufman, her husband and her neighbors kept busy with a wet-dry vacuum cleaner, to suck water out of the home.

"(Our home) is not on stilts so we always get it here," Kaufman said. The Fire Department pumped water out of Kaufman's yard for nearly three hours.

"We're trying to avoid this again," said Kaufman's friend Susan Griffiths-Seewerker, holding up a copy of the March 4 Honolulu Advertiser with a photo of Kaufman's flooded home.

Traffic was backed up in front of Rose Batalona's Waikane home as cars waited for the highway to reopen just before the Waikane Bridge. Batalona stood outside with her 9-year-old daughter, worried that rain could flood the streets again and send water gushing through her property.

Batalona lives just steps away from the Waikane Bridge and said she saw the raging stream jump its banks about 9 a.m.

"It's the worst I've ever seen it," she said.

On the Big Island, flooding closed Highway 11 from Na'alehu to Punalu'u. Pohaku Drive also was closed. A utility pole fell, knocking out power to about 3,800 customers from Pahala to Kealia.

Reach Peter Boylan at pboylan@honoluluadvertiser.com and Loren Moreno at lmoreno@honoluluadvertiser.com.