Santa May Show Up in Shirt Sleeves : Weather: Warmer weekend is expected after offshore air flow puts an end to recent chilly days.

If you were dreaming of a white Christmas, go back to sleep. But if visions of a bright, sunny, unseasonably warm Southern California beach day have been dancing in your head, run to the window and look out.

After weeks of chilly days and chillier nights, warm air spread across the Southland on Thursday, with similar weather forecast through the holiday weekend. With a high of 75 in Santa Ana, Christmas Eve was much warmer than the normal 64 degrees, although it fell far short of the record high of 86, set in 1947.

At Huntington Beach Pier, couples holding hands, senior citizens and children strolled along, enjoying the midafternoon 72-degree sunshine.

Some people peered over the railing at sunbathers and swimmers, or watched bare-chested men playing volleyball in the sand. Others looked through binoculars or snapped pictures of snow-capped mountains in the distance. At least 100 surfers dotted the sea, not because of the waves--which were only about a foot high--but because of the water’s warmth.

“It’s fantastic, it’s absolutely unbelievable,” said Jim Widman, 47, a visitor from Baltimore. Widman stood barefoot on the pier, wrapped in a blue and green towel, drying off after a dip in the 58-degree waters below.

“My mother thinks it’s too cold, but we think it’s wonderful,” he said. “We got to take our coats off and went swimming instead.”

The burst of warmth came from a high-pressure ridge and an offshore flow of air from the east, according to Steve Burback, a meteorologist with WeatherData, which provides forecasts for The Times. Weak Santa Ana winds warmed much of the coast, with the hottest spot in the county being 77-degree Newport Beach.

It was 74 in Anaheim, 73 in El Toro and 71 in San Juan Capistrano, according to WeatherData. The coldest place in the county was Dana Point, where the thermometer did not rise above 66.

Today should be sunny with highs in the 70s, Burback said. The weekend will see a cooling trend, with sea breezes returning and the highs in the low to middle 60s, he said.

At Huntington Beach, out-of-towners were a bit disturbed Thursday by the California sunshine.

“Christmas is different out here. It’s tough to get in the spirit,” said Bev Northam, 35, who lives in Massachusetts. “I left home with a foot of snow on the ground. It’s different. . . . I must admit, it’s nice.”

Tom Lenth, 22, home for his sister’s wedding from a two-year teaching internship in American Samoa, was disappointed with the Christmas Eve weather.

“In Samoa if it gets to 70 degrees it’s freezing cold. It doesn’t usually go below 80. The humidity is ungodly,” said Lenth, standing on the pier in shorts and sandals. “I was hoping to have colder weather than this, to be perfectly honest.”