graphic by BIVN

(BIVN) – The entire Island of Hawaiʻi was under a Flash Flood Warning as of 10 p.m. on Monday evening, as heavy rains were starting to move into leeward areas.

The windward side of the Big Island was soaked all day, prompting the Flash Flood Warning for much of the day. Several roads were closed, including Highway 11 in Kaʻū between the 57 & 62 mile markers. Evacuation shelters are open at the Keaʻau Armory in Puna, the Naʻalehu Community Center, and the Robert N. Herkes Gym in Pahala.

From the National Weather Service in Honolulu:

At 927 PM HST, radar and automated rain gauges indicated heavy rain falling over windward, southeast, and interior portions of the Big Island, with these showers starting to move into leeward Big Island. Rain was falling at a rate of up to 3 inches per hour. This has led to significant rises in water levels in streams and rivers, with emergency management reporting multiple road closures across windward and southeast Big Island. Flash flooding is ongoing or expected to begin shortly.

Forecasters say the heavy rain could continue for another day.

“With the support of an upper level trough setting up over the state and increased atmospheric instability, the threat of heavy rainfall and localized flooding will continue through tomorrow, with a westward shift in areas of concern as the surface trough progresses,” the National Weather Service wrote on Monday evening. “A Flood Watch remains in effect for Maui and the Big Island through tomorrow afternoon.”