Update 10:45 a.m.

The National Weather Service dropped a flood advisory for Hawaii island after heavy rains over south Hilo and Puna eased.

A flash flood watch remains in effect for Maui and the Big Island as unstable atmospheric conditions and moisture in the atmosphere could trigger more heavy rain and even thunderstorms through this afternoon.

Update 8:40 a.m.

The flood advisory for Hawaii island has been extended through 11:15 a.m. this morning.

The earlier flood advisory for the island of Maui has expired.

Weather radar at 8:06 a.m. showed moderate to heavy rainfall over portions of south Hilo ad Puna districts at up to 1 inch per hour.

Forecasters said the heavy rains are expected to continue for a few more hours.

Locations in the advisory inculde, but are not limited to, Hilo, Hawaiian Paradise Park, Honomu, Keaau, Ninole, Ookala, Laupahoehoe, Pepeekeo, Orchidland Estates and Hawaiian Acres.

Update 5:45 a.m.

Weather officials extended the flood advisory for Hawaii island and the island of Maui until 8:15 a.m. and 8:30 a.m., respectively.

At 5:02 a.m., weather radar showed heavy rain still falling near Hilo, at around 1 inch an hour.

Weather radar at 5:22 a.m. showed heavy rain near Kaupo on Maui. Rain was falling at a rate of up to 2 inches per hour.

Locations in the Maui advisory include but are not limited to Kaupo, Kipahulu, Nahiku, Keanae, Hana, Wailua, Kailua, Hamoa and Haleakala National Park.

Locations in the Hawaii island advisory include but are not limited to Hilo, Hawaiian Paradise Park, Honomu, Mountain View, Keaau, Ninole, Ookala, Laupahoehoe, Pepeekeo, Glenwood, Orchidlands Estates and Hawaiian Acres.

A flash flood watch remains in effect for both islands through this afternoon.

Update 2:14 a.m.

The National Weather Service in Honolulu has issued a flood advisory for Hawaii island until 5:15 a.m.

At 2:11 a.m., radar showed heavy rain near Hilo. Rain was falling at a rate of 1 to 2 inches per hour.

Locations in the advisory include, but are not limited to, Hilo, Hawaiian Paradise Park, Honomu, Mountain View, Keaau, Ninole, Ookala, Laupahoehoe, Pepeekeo, Glenwood, Orchidlands Estates and Hawaiian Acres.

“Rainfall and runoff will also cause hazardous driving conditions due to ponding, reduced visibility and poor braking action,” weather officials said.

A flash flood watch is also in effect for the Big Island through this afternoon.

Previous coverage

Heavy rains pounded parts of the Big Island and Maui, which are under a flash flood watch and flood advisory.

“At 11:22 p.m., radar indicated heavy rain near Kaupo. Rain was falling at a rate of 1 to 1.5 inches per hour,” said the Maui flood advisory, which covers Kaupo, Kipahulu, Nahiku, Keanae, Hana, Wailua, Kailua, Hamoa and Haleakala National Park. The advisory is in effect until 2:30 a.m. Wednesday.

The Hawaii island advisory is in effect until 2:15 a.m. and covers Hilo, Hawaiian Paradise Park, Honomu, Mountain View, Keaau, Ninole, Ookala, Laupahoehoe, Pepeekeo, Glenwood, Orchidlands Estates and Hawaiian Acres. “At 11:04 p.m., rain gauge reports indicated heavy rain falling near Hilo. Rain was falling at a rate of 1 to 2 inches per hour,” the Big Island advisory said.

Both islands are also under a flash flood watch until Wednesday afternoon, according to the National Weather Service. Forecasters said a “combination of abundant moisture and instability from an upper-level disturbance near Hawaii may trigger heavy rain and flash flooding through Wednesday.”

Web cameras on Mauna Kea also showed a light dusting of snow on the summit Tuesday afternoon.

Forecasters said southeasterly winds may bring vog to some islands. “We will have the potential for locally heavy rain through much of the state and a chance for thunderstorms for the Big Island this afternoon. Maui and Big Island look to be the highest threat for flooding,” they said.

The forecast calls for mostly cloudy skies with numerous showers in leeward areas and more rain in windward areas through Wednesday morning. Some of the showers could be heavy.

Highs will be between 83 and 88 degrees, but the weather could feel hotter because of the humidity.

Tradewinds should begin returning later Wednesday, but are likely to be light and forecasters said more afternoon showers are possible in leeward areas Wednesday afternoon.

The heavy rains prompted a brown water advisory for Pearl Harbor and Ala Wai Harbor.

The state Department of Health is asking the public to stay out of flood waters and storm water runoff, “due to possible overflowing cesspools, sewer manholes, pesticides, animal fecal matter, dead animals, pathogens, chemicals, and associated flood debris.”