The National Weather Service in Honolulu issued a flash flood watch for the entire state, including the Big Island, for tonight through early Saturday morning.
A flash flood watch means flash flooding is possible within the next 36 hours.
According to forecasters, an upper-level low pressure system moving in from the west, combined with converging low-level flow and moisture moving in from the east, will bring the potential for thunderstorms and locally heavy rainfall statewide.
The weather service predicts a 90% chance of heavy rainfall tonight and Friday, and an 80% chance on Friday night.
Flood-prone roads and other low lying areas could be closed because of elevated runoff and overflowing streams. Urban areas could receive more significant flooding and property damage because of rapid runoff.
The weather service advises everyone to be prepared to take action if a flash flood warning — which means flooding is already occurring or imminent — is issued. If you experience heavy rain or rising waters, head to higher ground immediately.
A flash flood watch means conditions are favorable for flash flooding. Flash flooding is life threatening. Do not cross fast flowing water in your vehicle or on foot.