Heavy rains lead to crippling floods in Hawaii. Scientists warn of more occurrences due to climate change.

Days of torrential rain have caused catastrophic flooding across Hawaii this week, which officials and climate scientists say are occurring more frequently as the planet warms.

The threat of heavy showers was forecast to continue at least through Wednesday and likely longer. The downpours first affected Maui, moved northward up the island chain to Oahu and Kauai, then circled around and hit the southernmost part of the Big Island, forcing evacuations, closing roads and destroying homes in the process.

"Widespread showers, some locally heavy, are expected statewide through Wednesday as a slow-moving low-pressure system lingers west of Kauai," the National Weather Service said. "With the low remaining nearby for the next couple of days, light south winds will prevail, and the potential for showers will remain elevated."

The entire state remained under a flash flood watch as of Wednesday afternoon. The island of Kauai and part of the Big Island of Hawaii were under a flash flood warning.

Gov. David Ige signed an emergency proclamation on Tuesday.

An evacuation order for hundreds of residents from Haleiwa, a town north of Honolulu, was lifted late Tuesday as the threat of flooding from torrential rains subsided, according to Hawaii News Now.

Honolulu firefighters Tuesday rescued a 27-year-old man after his truck was swept down a stream. They found him standing on the truck's roof. On Wednesday, they suspended another search for an individual a witness saw swept down a stream in Pearl City.

Nearly 2 feet of rain has fallen this week in Wahiawa on Oahu, AccuWeather said. Some places have picked up a half-month's worth of rain in only one day.

On Monday, officials initially thought that the Kaupakalua Dam in the Maui community of Haiku was breached by floodwaters, but county officials determined there was no structural damage after closer inspection.

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About six homes on Maui and two bridges were heavily damaged or destroyed, Maui County Mayor Michael Victorino’s office said.

“This has been unprecedented flooding," Victorino said in a statement.

"In fact, some of the residents have told me that this is the worst they've seen in over 25 years," he said on Facebook.

One Maui resident, Mark Alexander, said that within minutes, water was up to his chest. “It’s to my waist, it’s to my chest, and next thing you know, I see my icebox passing me,” he told Hawaii News Now.

On the Big Island, in addition to the rain at lower elevations, snow also was forecast to fall on the highest summits of Mauna Kea and Mauna Loa, where a winter weather advisory was in effect, the weather service said.

The frequency of intense rains are an indication people should be prepared for such events more often, said Pao-Shin Chu, a University of Hawaii professor and the state’s climatologist.

“Don’t think that this is like a once-in-a-hundred-years event that you’ll only see once in your lifetime. It is changing,” Chu said.

Less time is lapsing between them, he said. “So it could be once every 30 years. Who knows?” Chu said.

To better prepare for future disasters, he said it will be important for scientists to understand how weather was interacting with a warming climate to cause so much rain to fall in such a short period.

Overall, Hawaii has had less rain in recent decades and at times has been battling drought. Just Tuesday, the U.S. agriculture secretary approved a drought disaster declaration for parts of Maui County.

A 2010 report from the University of Hawaii’s Sea Grant College Program said rainfall declined 15% over the prior 20 years. Yet the same report said between 1958 and 2007, rain events with the heaviest downpours increased 12%, underscoring that more intense rainstorms are growing in number.

Honolulu Mayor Rick Blangiardi said the city will need to work with state partners to keep waterways clear of debris to help prevent future flooding.

“We need to get used to climate events like this,” Blangiardi said. “A tremendous concentration of rain in a small amount of time in focused areas is going to result in flooding anywhere. If we have situations like that, then we need to really approach and attack.”

Contributing: The Associated Press

This article originally appeared on USA TODAY: Hawaii floods: Scientists warn more devastation due to climate change