Dangerous flooding on Hawaii's Oahu island prompts evacuations, warning of possible dam collapse

(OAHU, Hawaii) -- Dangerous flooding is impacting Hawaii's Oahu island, prompting evacuations and a warning from local officials of a possible dam collapse, as major rains pummel the area for the second significant rain event in a week.

An evacuation order was issued early Friday morning local time for Haleiwa and Waialua, including areas near the Wahiawa Dam, according to Oahu Emergency Management, which warned that the dam "may collapse or breach at any time."

The dam "has not failed but is at imminent risk of failure," Oahu Emergency Management said mid-morning local time Friday.

"Potential for life-threatening flooding and catastrophic amounts of fast-moving water in downstream areas," the agency warned.

Hawaii Gov. Josh Green said the Hawaii National Guard has been activated and other resources are being deployed across Oahu amid the "severe storm."

"We are coordinating closely with state and county partners to support evacuations, open shelters, and keep our communities safe," he said on X.

The latest flood threat comes a week after a damaging flood event that washed away roads and damaged homes.

A flash flood emergency was issued for northern Oahu earlier Friday for "catastrophic" flooding. Local emergency personnel had reported "life-threatening flash flooding" early Friday across northern Oahu, according to the National Weather Service in Honolulu.

"Floodwaters have cut off road access in and out of Haleiwa, and widespread flooding of roadways and low-lying areas is ongoing," the NWS said, warning that "significant runoff continues to produce high water levels and dangerous flooding impacts."

The Hawaii Department of Transportation advised of several road closures in the area early Friday due to flooding.

Flood conditions were expected to worsen, with more heavy rain forecast for the region throughout the day. The NWS warned that mudslides could occur in steep terrain areas.

The heaviest rain will be Friday through Saturday for most islands -- with the Big Island getting the heaviest rain on Sunday. 

Thunderstorms will be possible at times, which may include damaging winds. 

Flood watches are in effect for the Hawaiian Islands through Sunday, with at least 2 to 7 inches of rain possible during the event.

ABC News' Kyle Reiman contributed to this report.

This is a developing story. Please check back for updates.

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