Update, 10 p.m.

The Big Island’s flood advisory has been extended to 1 a.m. Wednesday.

Radar this evening indicated heavy rain over the southeast slopes of the Big Island, with the heaviest rain falling between Naalehu and Pahoa. Rain was falling at a rate of 1 to 2 inches per hour.

Some locations that will experience flooding include Hawaiian Paradise Park, Hawaii Volcanoes National Park, Volcano, Glenwood, Mountain View, Wood Valley, Pahala, Hawaiian Acres, Orchidland Estates, Punaluu Beach, Pahoa, Kawa Flats, Naalehu, Fern Forest, Eden Roc, Fern Acres, Kalapana, Kurtistown and Ainaloa.

8:30 p.m.

The Big Island is under a flood advisory until 10 tonight.

Radar this evening indicated heavy rain over the southeast slopes of the Big Island, with the heaviest rain falling between Naalehu and Pahoa. Rain was falling at a rate of 1 to 2 inches per hour.

Some locations that will experience flooding include Hawaiian Paradise Park, Hawaii Volcanoes National Park, Volcano, Glenwood, Mountain View, Wood Valley, Pahala, Hawaiian Acres, Orchidland Estates, Punaluu Beach, Pahoa, Kawa Flats, Naalehu, Fern Forest, Eden Roc, Fern Acres, Kalapana, Kurtistown and Ainaloa.

Previous coverage

A powerful storm front is moving over the Hawaiian islands today, and the National Weather Service is warning residents that “gusty and erratic winds associated with strong thunderstorms may bring gusts near 50 mph, frequent lightning, visibility near zero in heavy rain, and the potential for small hail.”

A flood watch is in effect for Kauai, Niihau, Oahu, Maui, Lanai, Molokai and Kahoolawe through Wednesday afternoon. The Big Island is under a flood watch through Wednesday night.

In a special weather statement issued this morning, the weather service said, “A cold front moving over the islands will combine with a well-developed trough aloft, bringing the potential for strong thunderstorms to Kauai and Oahu and adjacent waters. Over Kauai, strongest storms are expected from the late afternoon through the evening, while on Oahu they are expected from late tonight through Wednesday morning.”

Kauai County officials are urging residents to be vigilant of potential severe weather conditions.

“With the forecast calling for gusty Kona winds, heavy rain, and possible strong thunderstorms, officials advise caution and avoiding non-essential travel and outdoor activities during inclement weather,” said Kauai Emergency Management Agency Administrator Elton Ushio. “In several recent Flash Flood Warning events, multiple residents and visitors had to be rescued after attempting to cross areas prone to flooding or flash flooding, such as roadways, rivers/streams and low-lying areas.”

“When thunderstorms approach, you should move indoors, and remain away from windows and electrical appliances,” the statement continued. “Remember that lightning can strike several miles away from a thunderstorm.”

The weather service further warns that “flood-prone roads and other low-lying areas may be closed due to elevated runoff and overflowing streams. Urban and leeward areas may receive more significant flooding and property damage due to rapid runoff.”

Forecasters said that the front is expected to stall and weaken near the Big Island on Thursday then dissipate by Friday.

They predict light and variable winds on Thursday, and light to moderate east to southeast winds on Friday and into the weekend, with high temperatures in the mid-80s and overnight low temperatures in the 70s.