Expect the wet and muggy weather to linger throughout the Hawaiian Islands at least through Thursday.

The National Weather Service Honolulu office has issued a flash flood watch for Oahu, Kauai and Niihau through tomorrow morning, bringing heavy rainfall and the possibility of thunderstorms.

But Weather Service forecaster Pete Donaldson said last night that residents through the island chain can expect unstable weather conditions until at least Thursday, when an upper trough hanging over the showers is anticipated to go away.

Honolulu residents were treated to a thunder-and-lightning show from about 5:30 to 7 last night. Most of the thunderstorms last night were confined to just off the southern shores, Donaldson said. "It was quite a bit stronger when it was over (the ocean) than when it came ashore," he said.

Chances remain for more thunderstorms to come ashore in the coming days, he warned.

The rain was not as heavy as some had expected. The highest amount of rainfall recorded from 2 to 8 p.m. yesterday was 0.29 inches in Manoa, Donaldson said.