Some 1,500 residents have already sought shelter in temporary evacuation centers, mainly in and around Honolulu
Torrential rains pummeled Hawaii on Friday as Hurricane Lane swirled toward the island state, triggering landslides, "catastrophic" flooding and prompting stark warnings from authorities.
In its 1200 GMT bulletin, the Honolulu-based branch of the National Weather Service said the now Category Three hurricane was packing winds in excess of 120 miles per hour (195 kilometers per hour).
Currently located some 200 miles south of the state capital Honolulu, Hurricane Lane's center was forecast to track over or "dangerously close" to parts of the main Hawaiian islands later Friday and into the night.
Brock Long, administrator for the Federal Emergency Management Agency (FEMA), warned of major disruptions to the power grid.
"Citizens need to realize that we are looking at major hurricane impacts and things are going to break," Long said.
"We need to set the expectation that the power could go off for quite some time and the infrastructure is going to be heavily impacted."
The archipelago's Big Island has already been deluged with "catastrophic flooding," the NWS said.
Over two feet of rain have fallen at several locations on the windward side of the Big Island, the National Hurricane Center said, with 30 to 40 inches possible over some areas throughout the state.
Emergency teams have set up 16 evacuation centers, with a further 19 due to open later as President Donald Trump, who has declared a state of emergency, urged Hawaiians to hunker down and prepare for the worst.
"Our teams are closely coordinating with the state and local authorities. You are in our thoughts!" Trump tweeted.
Some 1,500 residents have already sought shelter in temporary evacuation centers, mainly in and around Honolulu, said Brad Kieserman, vice president of Disaster Services Operations and Logistics for the American Red Cross.
"I definitely expect to see an increase in population as the storm continues to approach," he added.
United Airlines said it canceled all Friday flights to and from Kahului airport on Maui, the second-largest island.
The US Coast Guard said 57,000 US military personnel already stationed in Hawaii were ready to provide logistical and medical support or conduct search and rescue missions operations.
"Hurricane Lane is not a well-behaved hurricane," Governor David Ige said in a statement as he declared a state of emergency Tuesday on the Big Island.
"I've not seen such dramatic changes in the forecast track as I've seen with this storm."