Oahu received slate-gray skies, steady rain and wind gusts for Christmas that knocked out power to more than 18,000 people, downed trees, power lines and closed the Pali Highway — again — as the result of a mudslide.

At 2:45 p.m., heavy rain was falling at a rate of 1 to 2 inches per hour. The National Weather Service extended a flood advisory for Oahu in its wake.

Peak winds of 72 miles per hour were recorded at Makua Ridge, 48 at Marine Corps Air Station Kaneohe, 43 in Mokuleia, 40 at Schofield Barracks, 39 in Kalaeloa and 38 in Honolulu, according to the weather service.

It all added up to a soggy, blustery and traffic-delayed Christmas for many. Kakaako resident Chris Rose said the gusts seemed extra strong.

“It was actually very scary to be outside,” she said. “It was so strong that I was worried about something flying through the air.”

Her husband Mike said a big tree limb cracked off in the wind Tuesday night on South Street, and there was high surf Christmas morning. “I’ve never seen waves like that. It was crazy,” he said.

As of 5 p.m., the Honolulu Fire Department had responded to 27 downed trees, seven downed power lines, five arcing wires, seven blown roofs and two flooding evacuations (one in Mililani and one in Aiea).

“While downed tree calls were a little more prevalent on the Windward side, with 12 in Kaneohe alone, they were coming from all over the island, including Waikiki, Kalihi, Ewa Beach, Waipio and Mililani,” said Honolulu Fire Capt. Scot Seguirant.

“Downed trees can be bad, but I would say most of these were not real major, because they were mostly single company responses, with only a few with multiple trucks,” he said.

With the high winds and downed trees, multiple power outages occurred across the island.

Hawaiian Electric Co. late Wednesday morning reported 2,190 in the Waianae area, 2,231 in Maili and Nanakuli, 1,869 on the North Shore, 1,346 in the Mililani and Wahiawa areas, 611 in the Kahaluu area, 3,256 in Kailua and 1,421 from Hawaii Kai to Waimanalo.

The utility tweeted that by 4 p.m. power was restored to customers in Mililani Tech Park and Haleiwa, but crews continued to respond to outages in Hawaii Kai, Waimanalo, Kaneohe, Makaha, Waianae, Kailua, Kalihi, and Pearl City.

Additional crews were called in that morning to assist in restoring power, HECO said.

On the Pali Highway Kailua-bound, tree branches fell down the steep hillside between the two tunnels and onto part of the right lane. At first, the left lane was still open, but crews then started diverting all Kailua-bound traffic.

“Our fencing caught most of it but we will be clearing the loose material to reduce potential for additional debris to come down,” the state Department of Transportation tweeted, adding it was anticipating reopening Kailua-bound lanes last evening.

The Pali closure added to the frustration of Kailua residents who just five days earlier were told the nearly year-long Pali repair and repaving project was finished. DOT reopened the Pali Highway to traffic in both directions 24 hours a day, seven days a week on Saturday after extensive repairs following a major landslide on Feb. 18.

A weakening frontal band was expected to move from west to east causing continued showery and breezy weather, the National Weather Serv­ice said Wednesday evening. High pressure will build in behind the front with trade wind weather returning later this week and over the weekend.

Because of stormwater runoff, the Hawaii State Department of Health issued a brown water advisory for Oahu.