A 22-year-old man was critically injured by a power line felled by lightning in Kailua on Sunday as a thunderstorm drenched Oahu.

The high-voltage line came down on parked cars, causing them to smoke, and the man approached the cars with a fire extinguisher, officials said.

An Emergency Medical Services spokes­woman said the man put his hand on the car and was severely shocked in the process. He stopped breathing, but emergency responders were able to revive him, she said.

Paramedics took the man in critical condition to an area hospital.

The downed line caused about 1,700 Hawaiian Electric Co. customers to lose power at 9 a.m. near Kuu­lei and Kailua roads. The incident was initially reported as a downed power line on a car on Ohana Street.

Kailua resident Alan Lloyd said lightning hit the utility pole.

Crews worked to restore power to most of the 1,700 customers by 10 a.m., but about 25 houses closest to the incident remained without power until about 11 a.m.

Meanwhile, the weather temporarily stranded a group of hikers at the top of the Stairway to Heaven trail Sunday morning, a Hono­lulu Fire Department spokes­man said. A rescue crew responded to an 11 a.m. call for help, and HFD decided to suspend the mission around noon until the weather cleared up, Capt. James Todd said.

Todd said they made it out on their own sometime between noon and 3 p.m.

In Makiki, branches from a massive banyan tree fell onto Beretania Street and blocked all but one lane of traffic in front of its namesake Banyan Tree Plaza condo, a Hono­lulu Fire Department spokes­man said.

The tree fell just before 8 a.m., and no injuries or damage were reported, Todd of HFD said.

Todd said it was fortunate the accident did not happen on a weekday when the area is packed with commuters.

THE National Weather Service said unstable atmospheric conditions combined with moist southerly flow ahead of a surface front near Kauai brought periods of heavy showers and thunderstorms to Oahu. The front was expected to weaken Sunday night into today, allowing more typical tradewind weather to prevail most of the week.

The storm dumped heavy rain on Kauai on Saturday night and early Sunday, downing trees and closing roads and bridges, before moving over Oahu on Sunday afternoon, prompting the weather service to issue a flash flood watch for the island until 6 p.m.

On Kauai, heavy rain downed trees that closed the Hana­lei Bridge and the Kea­pana Bridge in Kapaa for several hours. One lane on the Hana­lei Bridge was reopened for contra-flow traffic Sunday morning after the rain eased.

The Red Cross briefly opened a shelter at Hana­lei School early Sunday.

In the 24-hour period ending at 5 a.m., Mount Wai­­al­eale got 12.2 inches of rain; the Waia­lua ditch and Wai­alae recorded 7.4 inches of rain; and Mana, Kilo­hana and the Mohihi Crossing saw about 6.8 inches.