Thousands of people in Hawaii have been told to evacuate their homes as the US state suffered its worst flooding in decades.

It is the second severe storm to hit the archipelago in the last week, causing damage that could exceed $1bn (£745m), according to Honolulu Mayor Rick Blangiardi.

More than 230 people have been rescued so far, Blangiardi told a news conference on Friday. Heavy rains continued to fall on the archipelago in the early hours of Saturday morning.

The authorities warned that a dam in Oahu, the state’s most populous island, was at risk of collapse. Blangiardi urged residents to “stay safe” and “take the storm as seriously as you can”.

Speaking at Friday’s news conference, Governor Josh Green said there had been no reported fatalities in the storms, and praised the emergency workers working to keep people safe.

Rising floodwaters lifted homes and cars and triggered evacuation orders for some 5,500 people north of the state’s capital city, Honolulu. Roads have been closed across the islands.

Honolulu Department of Emergency Management has issued multiple flash flood warnings and urged residents to move to higher ground and avoid flooded areas.

Flood watch warnings have also been issued for Maui, Molokai and The Big Island.

Green said the storm would have a “serious consequence for us as a state” because it had caused enormous damage to airports, schools, roads and hospitals, as well as people’s homes.

“This is the largest flood that we’ve had in Hawaii in 20 years,” he told the news conference.

The governor urged residents to seek out shelters and assembly areas across the state.

The island is the grip of a “Kona Low”, a slow-moving area of low pressure that pulls in warm, moisture-rich air across the Hawaiian islands, bringing heavy rain and flash flooding.

Some areas have seen more than 10 inches (25cm) of rainfall and winds of up to 100mph (160km/h).

The worst of the weather is now out of the way, though heavy showers and thunderstorms are likely in Hawaii for the rest of the weekend and into the start of next week.

The storm Is the latest challenge for the island, which frequently deals with the fallout of natural disasters such as the 2023 Lahaina wildfires, which left more than 100 people dead. (BBC)

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