(BIVN) – Hawai‘i County Civil Defense issued a hazardous weather message on Friday, citing a National Weather Service forecast for heavy rain, flash flooding, high surf, and the possibility of thunderstorms for Hawaii Island starting Saturday.

“Flash flooding means dangerous conditions of high, fast-moving water can occur on roadways without warning,” the emergency officials stated. “Quickly rising, fast moving water in streams and rivers can also occur without warning.”

As of Saturday morning, the only weather alert in effect for the Big Island was a Wind Advisory for the summits of Mauna Kea and Mauna Loa, where southwest winds of 35 to 50 mph are expected, with localized gusts over 60 mph. “Summit wind speeds will likely increase from Sunday night through Monday and a High Wind Warning for the Big Island summits may be needed during this period,” the National Weather Service stated Saturday morning.

Forecasters say “a shallow low level cold front with light to moderate showers” is moving through Maui County. “The remnants of this front will continue to move into the Big Island later this afternoon enhancing showers across the island,” forecasters say.

Civil Defense stated on Friday:

• Residents in flood-prone areas are advised to be on the alert for possible flooding conditions.​
• Motorists are urged to exercise caution while driving.
• Road closures may occur without notice.Persons near streams and rivers must remain alert for changing conditions.
• High surf may cause dangerous conditions for ocean users and coastal residents.
• If lightning threatens your area, the safest place to be is indoors.