Power went out briefly for nearly half of Hawaii island this morning as rain from remnants of Tropical Storm Barbara drenched the island, and the widespread power outages caused an array of traffic signals to fail, according to police and civil defense officials.

A spokeswoman for Hawaii Electric Light Co. said power was interrupted to about 42,000 customers on the island shortly before 10:45 a.m., but power was restored to all but about 1,600 customers in Hawaiian Ocean View Estates by about 12:15 p.m.

HELCO has a total of about 86,000 customers on the island.

Hawaii County Civil Defense officials said residents had called to report power out in the isolated Hawaiian Ocean View Estates area of Kau as well as in more densely populated areas such as Waimea. Power was also reported to be out in Honomu, Keaukaha and Waiakea in the Hilo area.

The HELCO spokeswoman said there were reports of some customers losing power in Kona as well.

The HELCO spokeswoman said the cause of the outage is still being investigated. She said the outage “is believed to be weather related,” but said she could not confirm reports that outages were triggered by a generator that tripped offline.

Hawaii island police warned at about 11:30 a.m. that “island wide traffic lights (were) malfunctioning,” and asked motorists to drive with care. Four-way intersections were treated as four-way stops when the signal lights fail, authorities said.

Police said at about 12:40 p.m. that most malfunctioning traffic lights had been restored. Police said the manlfunctions were caused by rolling blackouts, not a power surge as they had initially reported.

Hawaii island residents who have lost power should call HELCO at (808) 969-6666, and civil defense officials warned residents to stay away from downed power lines.