Clad in T-shirts and sunglasses, Washingtonians stepped outside yesterday, hitting the links, hauling out tulip bulbs and greeting a balmy January day with the giddiness usually reserved for the first days of spring.

Record-breaking temperatures in the high 60s called for gloating.

Best friends Jason Sher and Jack Strabo, second-graders at Jamestown Elementary School in Arlington, where classes resumed today, were on the telephone with the National Weather Service by 9 a.m. yesterday.

"They said it was 59 in Washington and that it would be 65," Jason said. "I changed into a T-shirt and got out!"

The hiatus from winter weather came to the region courtesy of two high pressure systems--one at ground level and the other in the upper atmosphere. Both trapped warm air over Washington and allowed still warmer air from the Gulf Coast states to hover, said forecasters at the National Weather Service in Sterling.

Records for Jan. 3 were broken at both Baltimore-Washington International and Reagan National airports, where the mercury hit 68. That's one degree higher than the BWI record for the day, set in 1997, and two degrees higher than National's record, which was set the same day.

This year, the area's winter weather is being governed by La Nina--the cooling of Pacific Ocean temperatures off the coast of South America. That keeps the polar jet stream farther north than normal.

"So we'll get fewer East Coast snowstorms, and overall temperatures for the winter, averaged out, will be higher," forecaster John Margraf said.

But the cabin-fever-afflicted won't have a long respite. Forecasters predict that a cold front moving eastward from Ohio--which they blamed for the lack of sunshine yesterday--should be in the area today, bringing showers and temperatures in the mid-30s to 40 by tomorrow.

With that prediction of a fickle future, Washingtonians wallowed in the great outdoors yesterday.

The temptations were many and mighty.

Barefoot and attired in T-shirts and shorts, sisters Kate and Claire Donegan shot hoops in their Great Falls driveway, their jackets tossed on the ground, the occasional mournful look directed at a nearby swimming pool.

"It was wintertime, we thought," said Claire, 9, a fourth-grader at Faith Christian School in Sterling, which was not in session yesterday.

"If [the pool] was open, we probably could jump in," added Kate, 11, a sixth-grader at Faith Christian.

Walking the lawn with her brow furrowed, the girls' mother, Lisa Donegan, 38, mapped out an entire afternoon's gardening activities. The dead petunias would get pulled, and the dusty miller would get trimmed.

For many working people, lunch outdoors was the only way to experience the first weather oddity of the new year.

Outside Beau Jolies Cafe in Northwest Washington, Gretchen Hurley and her friend Patrick Bowl finished up slices of pizza.

"The last time I sat out to eat was probably in October," said Hurley, 26. "I hardly expected to be sitting here in January."

The praying mantises stalking insects at Larry Krops's Christmas tree farm in Great Falls were proof that the weather was anything but wintry. Maintenance man Ron Rogers, 44, was mowing and planting seedlings, By lunchtime, he had counted dozens of the critters and was stripped down to T-shirt and sweat-stained ball cap--the better to do heavy outdoor work.

"A lot of times in winter, you come out in a heavy coat and you sweat and the whole nine yards," Rogers said. "Today's great. It feels just like a spring day."

At the Upper Marlboro Country Club in Prince George's County, the greens teemed with golfers in khakis and striped short-sleeve shirts, taking shots and critiquing each other's swings.

"You don't often get a day like this to play at this time of year without going to Florida," said John Pinkney, 51.

Not everyone was playing. Some took advantage of the weather to do chores that are impossible on cold days.

"This thing was hideously dirty," said Brian Palombo, 30, as he scrubbed dirt and salt from his black Ford Explorer at the E-Z Car Wash in Leesburg, where nearly a dozen cars were lined up for baths.

In Arlington County, workers rushed to put new stickers on 3,810 parking meters informing motorists that everyone, even the disabled, must pay to park.

The old blue-and-white stickers, with a handicapped logo, had confused visitors, county officials said, leading them to believe every meter was for the disabled. The new black-and-yellow stickers have a clearer message that everyone must pay. But county workers couldn't apply them until springlike weather arrived.

"The adhesive will stick at 60 degrees or more," county spokesman Richard Bridges said. County workers will complete the task on the next balmy day.

Staff writers Patrice Gaines, Steve Ginsberg, Maria Glod, Ann O'Hanlon, David Nakamura, Peter Pae and Christina Samuels contributed to this report.

CAPTION: The legs say it all. Joggers pass Tom Ray and Sean Lynch as they take a break at the Georgetown waterfront.

CAPTION: Dwani Wigglesworth and Tracy Shields enjoy the warmth in West Potomac Park. The forecast calls for temperatures in the mid-30s by tomorrow.