UPDATE 1:55 a.m.

Tropical Storm Darby continues to move toward Hawaii.

Just before 2 a.m., the tropical storm was located about 425 miles east of Hilo and 630 miles east-southeast of Honolulu, said National Weather Service forecasters.

Darby is expected to carry maximum sustained winds of 60 mph.

UPDATE 10:55 p.m.

The Central Pacific Hurricane Center issued a tropical storm warning for Hawaii island. A tropical storm watch remains in effect for Maui County.

Just before 11 p.m., Tropical Storm Darby was centered 460 miles east of Hilo and 660 miles east-southeast of Honolulu, moving west at 10 mph. It was packing maximum sustained winds of 65 mph.

Darby is expected to move northwest at about the same speed through Saturday evening.

Surf generated by Darby could possibly become damaging along some coastlines on Friday and Saturday.

UPDATE 6:50 p.m.

Tropical Storm Darby could drop as much as 10 to 15 inches of rain and bring tropical storm force winds of 39 to 65 mph to Hawaii island starting as early as Friday night, National Weather Service forecasters said tonight.

Forecasters said tropical storm conditions are possible on Hawaii island from Friday night until Sunday night; Maui from Saturday until Sunday night; Lanai from Saturday until Sunday night; Molokai from Saturday until Monday; Oahu from Sunday until Monday; Kauai from Sunday night until Monday.

However, forecasters caution that the track of the storm, its intensity and the timing of the storm could change.

Forecasters and emergency officials said people should take precautions now, while the weather is still good, to prepare for a possible tropical storm coming ashore on Hawaii island and Maui in the next 48 hours.

“For those under a watch, now is the time to prepare,” forecasters said. “Secure or bring indoors any loose outdoor objects like lawn furniture, children’s toys, hanging plants, barbecue grills or any thing that could become a destructive projectile in strong winds. Do not wait until it is too late.

“Stay calm and keep informed. Closely monitor NOAA weather radio or other local news outlets for official storm information. … Be ready to evacuate if necessary. Heed the advice of local officials and comply with any orders that are issued. Persons living near the shore should be prepared to evacuate quickly should building surf threaten.”

A high surf advisory is in effect for east shores of Hawaii island and Maui County until 6 a.m., when it will turn into a high surf warning.

Forecasters expect surf of 12 to 20 feet until 6 a.m. Sunday.

Hawaii County plans to open emergency shelters on the Big Island at 4 p.m. at Hilo High, Waiakea High, Kalanianaole Elementary, Keaau High, Pahoa High, Laupahoehoe Community Charter School, Honokaa High and Intermediate, Kohala High and Elementary, Waikoloa Elementary, Kealakehe High, Konawaena High, Kau High and Mountain View Elementary schools in anticipation of the storm.

In addition, all camping and pavilion reservations are canceled at county parks from Friday to Sunday.

County swimming pools and the Honolulu Complex will be closed, and the lava viewing area in Kalapana is also closed from Friday until Sunday.

The National Weather Service also posted a tropical storm warning for waters 40 to 240 nautical miles off the Hawaiian islands, including portions of at the Papahanaumokuakea Marine National Monument east of French Frigate Shoals.

Surf could reach 10 to 17 feet, and tropical storm force winds are expected.

UPDATE 4:45 p.m.

Just before 5 p.m. Tropical Storm Darby was packing maximum sustained winds of 65 mph and was centered about 500 miles east of Hilo and 695 miles east-southeast of Honolulu, moving west at 13 mph, the Central Pacific Hurricane Center reported.

A tropical storm watch is in effect for Hawaii island and Maui County.

Darby is expected to bring heavy rains that could cause “life-threatening flash floods as well as rocks and mud slides” to Hawaii island and parts of Maui County late Friday, potentially impacting the rest of the state on Saturday, forecasters said.

Tropical storm-force winds are also possible over Hawaii island and parts of Maui County on Saturday.

Forecasters expect the center of Darby to pass very close to, or over, Hawaii island on Saturday with a slight decrease in forward speed late Friday into Saturday.

PREVIOUS COVERAGE

The National Weather Service has issued a tropical storm watch for Hawaii island and Maui County as Tropical Storm Darby continues on a path that could take it near or over the eastern end of the state.

The watch means that tropical storm-force winds of 39 mph or higher are possible within 48 hours.

The watch is in addition to a high surf warning and flash flood watch for the Big Island and Maui.

The flash flood watch will be in effect from late Friday night through Sunday afternoon, forecasters said.

“Depending on (Darby’s) exact track, there is the possibility of intense rainfall and flash flooding this weekend. The greatest risk of flash flooding will be to east- and southeast-facing slopes,” they said this morning.

Tropical Storm Darby maintained its strength as it headed west toward the Big Island and Maui with high winds, surf and rain over the weekend.

“Heavy rains associated with Darby are expected to reach the Big Island and portions of Maui county late Friday, potentially impacting the remainder of the state Saturday and Sunday. These rains could cause life-threatening flash floods as well as rock and mud slides,” forecasters said.

At 2 p.m., the former hurricane was packing maximum sustained winds of 65 mph and was centered about 540 miles east of Hilo and 735 miles east of Honolulu, moving west at 14 mph, according to the Central Pacific Hurricane Center. Tropical storm-force winds extend up to 105 miles from Darby’s center.

Forecasters estimated this morning that Hilo has a 64 percent chance of experiencing tropical storm-force winds of 39 mph or higher. There’s a 53 percent chance of tropical storm winds in Kailua-Kona; 51 percent in Kahului; 48 percent in Lanai City; 46 percent in Kaunakakai, Molokai; 38 percent in Honolulu and 25 percent in Lihue.

The weather service’s high surf warning will be in effect from Friday morning through 6 a.m. Sunday for eastern shores of Maui and the Big Island, as Darby-fueled surf reaches the eastern part of the state.

The warning, issued this morning, will replace a high surf advisory in effect from 6 p.m today until 6 a.m. Saturday, forecasters said.

The advisory continues for Oahu, Molokai and Kauai County.

Surf will climb today and tonight on eastern shores, reaching 12 to 20 feet Friday with occasional higher sets and continuing through at least Saturday night, forecasters said.

“Large breaking surf, significant shore break, and dangerous currents make entering the water very hazardous. Anyone entering the water could face significant injury or death,” forecasters said. They warned the public to expect:

» Ocean water surging and sweeping across beaches, coastal benches, and lava flows creating the potential for impacts to coastal properties and infrastructure, including roadways;

» Powerful longshore and rip currents at most beaches;

» And large breaking waves and strong currents, affecting harbor entrances and channels.

Oahu, Kauai and Molokai, meanwhile, are under a high surf advisory for eastern shores from 6 p.m. today to 6 a.m. Saturday. Waves are expected to climb to 5 to 8 feet tonight, then 8 to 12 feet Friday, according to the weather service.

The Air Force Reserve “Hurricane Hunters” are flying to Hawaii to help forecasters track Darby. The first flight is scheduled to fly through the storm on Friday.

Forecasters said rains ahead of Darby’s center are expected to begin falling tonight on Hawaii island.

“More significant bands of heavy showers and squalls associated with Darby are likely to start Friday night, then increase in intensity and frequency as the tropical storm gets closer,” forecasters said.