Rainfall of as much as 1 inch per hour over Barbers Point and Makakilo and offshore from Barbers Point to Hawai'i Kai this morning prompted the National Weather Service to issue an urban and small-stream flood advisory for several Honolulu communities, from Kuli'ou'ou to Waimalu.

The advisory was expected to last until 10:45 a.m. today.

Thunder and lightning were reported over Mililani.

Kaua'i and Ni'ihau were put under a flash-flood watch through today.

The front that has produced the storms is moving slowly east northeast and will put a damper on most outdoor weekend plans, said Bob Farrell, lead forecaster today for the weather service.

"It's not looking really great," he said this morning. "But it probably will not be as wild as it is today. Right now it is in its peak."

Heavy rain soaked parts of O'ahu yesterday. The rain was concentrated in Central O'ahu and parts of Windward O'ahu yesterday, but there were no reports of flooding or damage.

Forecaster Norman Hui said it will continue to be on the humid side because of the light southerly winds.

Hui said the wet, muggy weather is a little unusual for this time of year.

"If it's a real winter system, it'll come in, bring us the rain and then clear out," Hui said. "But what it is is we have this low-pressure trough just kind of sitting west of us, and from time to time it gets close and gives us this kind of weather and it's been like this for at least the past couple of weeks."

He said the rain probably won't be as heavy as on Saturday, when more than 10 inches of rain fell in Manoa Valley and caused major flooding and damage. However, Hui said because the ground is so saturated, "it doesn't take much more for flooding to occur."

The wet spots yesterday on O'ahu were at 'Ahuimanu, Waihe'e, Luluku, Wilson Tunnel, Maunawili, the airport, Schofield Barracks, Moanalua and Waiawa, where at least 1 inch of rain fell during the 24-hour period ending at 8 p.m.

Pau-hana traffic was heavy as commuters slogged through slick roads with limited visibility. To make matters worse, a truck overturned in the Wilson Tunnel, prompting police to close both Kane'ohe-bound lanes from 5:16 p.m. to about 7:30 p.m.