A flood advisory was in effect on Oahu for most of Wednesday because of locally heavy downpours that slowed traffic and turned some intersections into ponds.

The advisory was due to expire at 9:15 p.m.

Flooding was reported earlier on the H-1 freeway in the Ewa direction near the School Street onramp.

Water also collected on the Liliha Access Road overpass and on Dillingham Boulevard in Palama.

The rain, widespread and heavy in spots, was also reported in Waianae and in windward and central Oahu. The advisory included Maili, Nanakuli, Hauula, Laie, Kapolei, Makakilo, Aiea, Salt Lake, Halawa, downtown Honolulu, Kaaawa and Waiahole.

Rainfall of more than 3 inches an hour were estimated in some places.

The state Health Department, meanwhile, issued a brown-water advisory for Keehi Lagoon and Waimea Bay. Health officials advised the public to stay out of floodwaters, storm water runoff and brown, turbid coastal waters due to possible overflowing cesspools and sewer manholes and the possible presence of pesticides, animal fecal matter, dead animals, diseases like leptospirosis, chemicals and debris.

The chance of rain is expected to slowly diminish through Friday as conditions improve and tradewinds begin to return.

A weak surface ridge to the north will keep winds light for the day or so, the National Weather Service said. The ridge will strengthen during the weekend, allowing moderate trades to return, the agency said.

Drier and more stable air will move in through the next few days.