UPDATE: 12:45 a.m.

The National Weather Service issued a flash flood warning for the entire island of Maui.

Radar tonight indicated heavy rain continuing over Maui. The most intense rain was over the Wailuku and Waikapu areas with rates of 1 to 2 inches over saturated ground. The Maalaea area of south Maui, which had flood impacts earlier this weekend, and the Honoapiilani Highway from Maalaea to Lahaina will be vulnerable to flooding impacts, as well poor drainage areas in Wailuku and Kahului.

The Honopou Stream gage on the windward Haleakala slopes also showed a rapid increase in water level.

This warning is through 3:15 a.m. but will be extended if flooding persists.

Molokai’s flood advisory has expired.

9:45 p.m.

Molokai’s flash flood warning has been replaced with a flood advisory until 12:30 a.m. Sunday.

Radar this evening indicated moderate to heavy rainfall moving across the island from the northeast for the next several hours. Rain rates of 1 to 2 inches per hour can be expected.

6:30 p.m.

While rainfall has eased over the islands, a flash flood warning remains in place for Molokai until 9:45 p.m.

Stream gages showed runoff levels were still elevated and the Maui Emergency Management Agency reported that Kamehameha V Highway was still flooded in the Kawela and Kamalo areas, the National Weather Service said in an update.

Forecasters expect additional rainfall to move over the island from the northeast over the next several hours.

5:30 p.m.

The National Weather Service extended a flash flood warning for Molokai until 6:45 p.m.

Rain was falling at a rate of 1 to 2 inches per hour as of 3:35 p.m., according to radar data.

A shelter was opened near Kaunakakai for those affected by area flooding, NWS said in an update.

12:45 p.m.

A flash flood warning for Molokai has again been extended and is scheduled to expire at 3:45 p.m.

Radar data indicated heavy rain over the island with rainfall rates reaching 1 to 2 inches per hour. Other areas were seeing higher amounts of rain.

Rapid water level rises were recorded in Kawela Gulch and Kaunakakai Gulch.

Forecasters said rainfall is expected to diminish in the short term, but it could quickly return over the next few hours.

10 a.m.

A flash flood warning for Molokai has been extended until 12:45 p.m., but has expired for the island of Maui.

“At 9:30 AM HST, radar indicated heavy rain continuing to fall over a large portion of the island of Molokai, with peak rain rates near 2 inches per hour.,” the National Weather Service said. “Water levels in gulches and streams remain elevated, and flash flooding is ongoing.”

PREVIOUS COVERAGE

State emergency management officials are urging residents and visitors to be prepared for heavy rain and possible flooding as a rainy weather system over Hawaii has put much of the island chain under a flood watch through Sunday afternoon.

So far, Maui County has felt the brunt of the storm system which started Friday, with Pukalani and Kula in Upcountry Maui getting more than 5 inches of rain in 24 hours, the National Weather Service said at 7:45 a.m.

Flash flood warnings are in effect until 10 a.m. for the island of Maui, and until 9:45 a.m. for Molokai.

The Hawaii Emergency Management Agency said the risk of hazardous weather will move from east to west across the state over the weekend.

“This weather pattern presents several different hazards at different places within the state, and we’re urging our residents and visitors to be careful and prepared,” said Luke Meyers, HI-EMA’s administrator, said in a statement late Friday. “Sign up for your local county alerts to be sure you receive the most up to date and reliable information.”

Oahu could see winds gusting to 45 mph by Monday, while Kauai also may get high winds and rain, HI-EMA said.

Heavy rain on Friday across windward Maui closed roads, flooded low-lying areas and led to the critical injury of a Maui firefighter who was swept down a storm drain, officials said.

RELATED STORY: Firefighter swept into storm drain as Maui pummeled by rain

The Maui Emergency Management Agency activated its Emergency Operation Center and asked residents to report structural property damage online, HI-EMA said.

The National Weather Service in Honolulu has issued a flood watch through Sunday afternoon for all islands from Oahu to the Big Island.

“The bulk of the rainfall is expected to fall over windward slopes and coasts, but some heavy showers could spread to leeward areas, where stream flow could also become elevated,” forecasters said.

The heavy rain may expand to Kauai by Sunday afternoon, and locally heavy rain and possible thunderstorms are forecast through Monday, especially over windward areas, they said.

Gusty winds are expected from Kauai to Oahu through early Monday, the weather service said.

A winter storm warning is also in effect until Sunday evening for the summits of Mauna Kea and Mauna Loa on the Big Island, with freezing rain and up to 6 inches of snow expected.