Oahu’s flash flood warning expires, but threat of severe weather remains

HONOLULU (HawaiiNewsNow) - Oahu’s flash flood warning has expired as drenching rains subsided early Tuesday, but light showers continue — and the threat of severe weather remains.

Flooding also remained a concern island-wide due to continuing runoff.

The torrential rain caused significant problems across the state, but especially on Oahu.

Late Monday night, Hawaiian Electric crews reported a significant power outage in the Downtown Honolulu area. HECO said the Iwilei Substation was reportedly flooded, and the extended outage was likely to impact businesses and residents into Tuesday.

Crews are on scene, but water cannot be pumped out until the rain stops, HECO said. Customers in the area should plan ahead.

The Honolulu Fire Department reported evacuating multiple people from a home in Pearl City around 7:30 p.m. Among those rescued included an elderly woman who was trapped in a room by flood waters.

“The entire home was later evacuated after a side wall of the house had collapsed from the flooding water around their home,” HFD said.

On Monday afternoon, firefighters also responded to a swollen drainage canal following reports that five children had been swept away in floodwaters. Three of the kids were able to get out on their own while two needed to be rescued. And all of the children escaped with only minor injuries.

And earlier in the day, a tree falling on Pali Highway narrowly missed a driver, who captured the ordeal on camera. Bystanders and emergency crews were able to clear the roadway.

All of the rain overnight comes on top of several inches of rainfall that fell earlier throughout the day.

Preliminary 48-hour rainfall totals on Oahu included 7.36 inches at Poamoho, 5.66 inches at Nuuanu and 5.56 inches at the St. Stephen’s Diocesan Center in Windward Oahu. Even leeward areas got significant rainfall, including Makua Range with 5.18 inches and Waianae Valley with 4.14 inches. In addition to heavy rains, wind gusts of up to 55 mph were possible in some spots.

The governor has declared a state of emergency for the state due to the flooding rains, part of a low pressure system sweeping across the islands. Honolulu’s mayor has also made a disaster declaration.

In a news conference Monday afternoon, Honolulu Mayor Rick Blangiardi urged residents to remain vigilant. “This is a very serious storm,” Blangiardi said.

Island-wide on Sunday, firefighters responded to 47 storm-related calls, including damaged roofs and downed trees. And at least 19 people on Oahu sought refuge at emergency shelters.

Drenching showers hit Hawaii Island and Maui County on late Sunday into Monday, downing trees, flooding roads and homes and triggering power outages. On Sunday night, Kahului Airport went dark until crews could get backup generators online. Passengers had to deplane on the tarmac after waiting on board for hours.

The National Weather Service has called the Kona low impacting the state unusually strong and said it brings the threat of “catastrophic flooding” ― as much as 25 inches in some isolated spots.

Ahead of the storm’s worst impacts, Gov. David Ige on Sunday urged residents to prepare for the potential of major flooding, landslides, road closures and damage to homes.

“Now is the time to make sure you have an emergency plan in place and supplies ready should you need to move away from rising water,” he said, in a news release.

“When you are ready, please make sure that your neighbors have what they need, as well.”

Forecasters are predicting many communities will see 10 to 15 inches of rain, while some isolated areas could see 20 to 25 inches. “Rain events of this size can cause catastrophic flooding and affect areas that do not usually flood, such as Leeward areas,” the National Weather Service said.

“Many roads could become impassable due to severe runoff. Numerous landslides are also expected. Debris in streams and gulches may clog bridges and culverts resulting in dangerous flooding.”

In addition to the heavy rains, forecasters are warning about the threat of strong winds. The weather service warned wind gusts of 50 mph are possible through Monday night in some areas.

The city and American Red Cross of Hawaii have opened four emergency shelters for impacted households. As of Monday afternoon, 19 people had used the shelters.

The shelters are at:

• Kalakaua District Park
• Makaha Community Park
• Sunset Beach Park
• Kailua District Park

Pets are allowed in crates, and people are asked to bring their own supplies.

This story will be updated.

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