The upper Wailua area had more than 9 inches of rain in the 24 hours ending at 5 p.m. today. Hanalei had 7 inches and coastal areas on the east and north sides collected 3 to 5 inches of rain, all accompanied by bolts of lightning and blasts of thunder that lasted through last night and into midday today.

The heavy weather was expected to move across O'ahu and to Maui County tonight. A flash-flood watch was in effect through tomorrow.

On O'ahu today, an early morning waterspout off Kalaeloa Barbers Point Harbor caused a lot of excitement but little or no damage.

"The waterspout was sighted at around 8:45 a.m.," said state Department of Transportation spokesman Scott Ishikawa. "The harbor agent warned tenants and users to be prepared in case the waterspout headed to shore."

However, Ishikawa said it was his understanding that the waterspout remained offshore and dissipated at around 9:15 a.m., causing no damage.

On Kaua'i, state Department of Health officials authorized the posting of no-swimming signs in Kalapaki Bay at Nawiliwili this morning, after two sewer lines burst at the Kaua'i Marriott resort, one of them in a sinkhole that developed during the New Year's Day flooding.

But people shouldn't be swimming in muddy coastal waters anywhere, officials said.

"The storm water runoff is not a good place to be. Storm water quality is as bad or worse than a sewage spill," said Watson Okubo, monitoring and analysis branch chief in the Health Department's Clean Water Branch. He said recent tests show that bacteria counts in major stormwater flows without sewage can be as high or higher than those involving sewer system failures.

Rivers washed branches and trees down from the mountains, but also brought man-made debris to the shoreline. At Kealia Beach, two 55-gallon drums, tires, mailboxes and other debris piled up along the river amid driftwood. The coastal waves were black with mud, bark and logs.

Flooding closed roads at various times in Wailua Homesteads, Hanalei and in front of the Kaua'i Community Correctional Center and elsewhere. Police reported four landslides on Kuhio Highway at Waikoko and Wainiha on the north shore, but said equipment was delayed getting to them because the Hanalei River had overflowed onto the road.

On O'ahu, Kailua was the wettest spot today, with about 2 1/4 inches of rain in the 24-hour period ending at 5 p.m. Lana'i City also had 2 1/4 inches of rain.

Advertiser staff writers Will Hoover and Curtis Lum contributed to this report.