Most of Hawaii is under a flood watch for March 22 after "catastrophic" flooding swept away homes, covered roads and threatened dams in the state.

The Hawaii State Department of Health issued the advisory and recommends that everyone avoid ocean water for at least 72 hours after the last rainfall.

Thirteen public schools on Oahu, Hawaii island and Molokai will be closed Monday or for the week for storm-related damage assessments, cleanup and repairs, according to the Hawaii State Department of Education.

The worst flooding to hit Hawaii in two decades swept homes off their foundations, floated cars out of driveways and left floors, walls and counters covered in thick, reddish volcanic mud.

OAHU, HI -More than 5,500 people have been evacuated as the Hawaiian island of Oahu suffered its worst flooding in over 20 years, authorities said. Hawaii Governor Josh Green noted that conditions remain dangerous because the ground is already saturated, meaning it will take much less rain to trigger flooding, road closures and damage.

Hawaii’s worst storm in 20 years battered Oahu on Friday, with damage projected to exceed $1 billion, as relentless rain triggered widespread flooding, forced mass evacuations, stranded residents, and prompted at least 233 rescues while driving streams and reservoirs — including the aging Wahiawa Dam — to dangerous levels.

Catastrophic flash flooding on Oahu forced more than 5,500 evacuations and pushed the 120-year-old Wahiawa Dam to dangerous levels Friday. The dam has since receded but evacuation orders remain in place as more rain is expected. Yankees manager Aaron Boone hinted at concerns about Gil's health and velocity influencing his decision.