“Don’t take this storm lightly,” Green said in a video statement. No deaths had been reported, he said, but there have been few serious injuries.
The state has activated a programme for people displaced by the storm that allows them to get discounted hotel rates.
In a subsequent post, the governor warned that, because the ground had already been saturated by the earlier rainfall, “it will take much less rain to trigger flooding, road closures and damage”.
The damage from the storms 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.
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, he 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 has 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 on Friday.
