Guillermo was downgraded to a tropical depression Thursday afternoon but remained on a path bringing it close to the North Shore of Oahu and possibly over Kauai in the next two days.

The Central Pacific Hurricane Center warned that Guillermo will continue to produce large “life-threatening surf” on east shores of most islands, with smaller waves Friday.

The center of Guillermo was expected to pass within 30 miles north of Oahu and Kauai late Thursday night and Friday.

At 8 p.m. Thursday the eye of the storm was 113 miles northeast of Oahu, with maximum sustained winds of 35 mph and higher gusts, moving west-northwest at 9 mph.

The strongest wind and rain are mostly in the northeast quadrant, away from the islands. There were no storm watches or warnings for any island.

Guillermo is expected to weaken further to a remnant low Friday as it passes near or over Kauai, with dissipation expected Saturday, forecasters with the Central Pacific Hurricane Center said.

Guillermo took a more westerly, rather than west-northwest, path, bringing it closer to the northern islands Thursday, but was gradually turning west-northwest Thursday night and was expected to continue on that track.

Forecasters said there was a chance of thunderstorms across the state because of the instability and tropical moisture from Guillermo, and more rain could come after Guillermo passes as a band of clouds and moisture behind the storm moves over Hawaii through Friday.

Guillermo will also cut off the tradewinds during its passage, bringing more hot and humid weather.

Meanwhile, Tropical Storm Hilda formed Thursday in the Eastern Pacific and was expected to become a hurricane Friday. Its path, similar to Guillermo’s, takes it close to Hawaii as early as next week, but it’s too soon to say how it will affect the weather in the islands. Hilda is the 10th storm in the Eastern Pacific this hurricane season.

Hilda is expected to strengthen into a hurricane Friday and cross into the Central Pacific on Saturday. At 5 p.m. Thursday, Hilda was 1,510 miles east-southeast of Hilo with maximum sustained winds of 60 mph, moving west at 14 mph.

Forecasters say Hilda might come close enough to have an effect late next week.

Meanwhile, surf generated by Guillermo prompted a high-surf warning for east shores of Maui, Molokai, Oahu and Kauai with waves of 10 to 15 feet expected at least until 6 a.m. Friday. A high-surf advisory was posted for eastern shores of Hawaii island with waves of 8 to 12 feet.

A small-craft advisory is in effect for waters off Kauai and Oahu through Friday evening.

Honolulu lifeguards urged people to stay off shoreline ledges, where waves could wash people into the ocean, and said only experts should be in the water.

Waianapanapa State Park on Maui remained closed Thursday because of the surf but was expected to reopen Friday. People were urged to stay clear of the blow hole, black-sand beach and coastline areas, officials said.

On Kauai the Department of Land and Natural Resources reopened the Kalalau Trail to Hanakapiai Stream in Na Pali Coast State Wilderness Park on the island’s north shore.

State officials urged hikers to exercise caution when crossing streams and to be prepared for changing weather.

Tropical storm warnings and watches are also posted for seas around the Hawaiian Islands where high seas and tropical storm conditions are possible. The warning includes a portion of the Papahanaumokuakea Marine National Monument east of the French Frigate Shoals.

For the next week, highs throughout the state are expected to be between 86 and 91 degrees, and wind should be from the east at 15 to 20 mph. On Thursday, Hilo tied a record high temperature of 88 degrees set in 1959.

Tradewinds should return over the weekend after Guillermo and its remnant moisture pass, forecasters said.