UPDATE: 11 p.m.

Tropical Storm Darby is expected to bring large swells and rainfall to parts of the Hawaiian islands this weekend.

At 11 p.m., Darby was 300 miles east-southeast of Hilo and 515 miles east-southeast of Honolulu with winds at 45 mph. Darby is moving toward the west at 21 mph and this motion is expected to continue through the weekend. Darby’s center is expected to be south of the Big Island on Saturday.

Large swells generated by Darby are expected to affect portions of the state over the weekend. Darby is expected to produce rainfall of 2 to 4 inches along portions of windward Big Island and windward Maui.

Darby is expected to weaken into a post-tropical remnant low late Saturday before dissipating on Sunday.

5:35 p.m.

Tropical Storm Darby is expected to dissipate by the end of the weekend but not before dumping heavy rain on the Big Island, and high surf to all islands as it moves south of the state.

At 5 p.m., Darby was 400 miles east-southeast of Hilo, with maximum sustained winds of 45 mph, moving west at 20 mph, said forecasters with the Central Pacific Hurricane Center in Honolulu.

The small, fast-moving storm is expected to weaken to a tropical depression then a post-tropical remnant low Saturday as it passes south of the islands.

However, large swells generated by Darby are expected to affect areas of the Hawaiian islands this weekend, forecasters said. “These swells are likely to produce hazardous surf and dangerous rip current conditions,” they said.

In addition, the National Weather Service has issued a high surf warning this weekend for south shores as a “historic” South Pacific swell reaches the islands.

Darby is also “expected to produce localized storm total rainfall of 2 to 4 inches along portions of mainly windward Big Island and windward Maui,” CPHC forecasters said. “These rains may cause nuisance flooding especially in low-lying and poor drainage areas.”

3:30 p.m.

Hawaii County officials said they will close south-shore beach parks this weekend ahead of expected high surf and rough ocean conditions as the weakening Tropical Storm approaches the island from the southeast and combines with a large swell from the South Pacific

Waves are expected to be between 15 to 20 feet Saturday and Sunday.

Officials said the beach parks may stay closed until Monday if the weekend waves cause debris in the parks.

11 a.m.

Tropical Storm Darby continues to weaken as it moves toward the Hawaiian islands, according to the Central Pacific Hurricane Center in Honolulu.

At 11 a.m., the center of Darby was about 505 miles east-southeast of Hilo, with maximum sustained winds of 60 mph and higher gusts. Darby continues moving west at about 20 mph.

Forecasters expect Darby to weaken to a tropical depression tonight, and become a post-tropical cyclone Saturday as it passes south of Hawaii island.

The National Weather Service of Honolulu says breezy tradewinds will increase to gusty winds from Saturday into Sunday as Darby passes Hawaii.

These stronger winds may approach wind advisory levels, as well as meet critical wildfire weather thresholds for some leeward areas on Saturday, NWS forecasters said today.

More showers are also expected throughout Saturday, especially for portions of Maui and Hawaii island, which could get up to 2 to 4 inches of rain, mainly on windward sides. These rains, officials warned, may cause nuisance flooding in low-lying and poor drainage areas.

Forecasters said swell energy from Darby is expected to arrive tonight, and peak on Saturday, affecting mainly the eastern shores of Hawaii island, where a high surf advisory may be required on Saturday.

Separately, a new south swell is expected to pump surf along southern shores to well above average levels this weekend, according to NWS, though no surf advisory for those shores had been issued as of late this morning.

“The initial forerunners of a new, large south swell will likely arrive later today or tonight,” weather service officials said. “Surf produced by this swell is expected to peak on Saturday, with heights near the high surf warning threshold of 15 feet along south-facing shores.”

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Now a tropical storm, Darby is expected to bring strong winds, large swells and showers to the islands this weekend as it continues to weaken while passing south of Hawaii.

As of 5 a.m. today, the center of Tropical Storm Darby was located about 605 miles east-southeast of Hilo with maximum sustained winds near 70 mph with higher gusts, according to the Central Pacific Hurricane Center in Honolulu.

A tropical storm warning is in effect for Hawaii’s offshore waters from 40 to 240 nautical miles including the portion of the Papahanaumokuakea Marine National Monument east of French Frigate Shoals.

Forecasters expect easterly winds to increase to 30 to 40 knots tonight with seas building to 10 to 14 feet with isolated thunderstorms in southeast waters.

Weather officials expect breezy tradewinds to increase in strength for the rest of the islands, possibly to advisory levels, as Darby passes south of the islands Saturday into Sunday. Shower activity is also expected to increase, especially for some areas of Maui and Hawaii island, over the same period, with windward and mauka areas getting most of the rainfall.

Weather is forecast to return to breezy trades with passing showers on Monday.

Darby is expected to weaken into a post-tropical remnant low late Saturday or Saturday night before dissipating on Sunday.

Tropical-storm-force winds extend outward up to 60 miles from Darby’s center.