Sunshine, clear skies and unseasonably warm temperatures boosted spirits yesterday and gave the Washington area a taste of springtime, which is officially just a few weeks away.

Yesterday's high temperature, 67, the highest so far this year, was 12 degrees short of the record high for the day, set in 1923. The normal for March 3 is 49 degrees, according to the National Weather Service. Temperatures, which have been above normal all week, are expected to be in the high 60s again today. They will return to near normal--the high 40s--by the end of the week, forecasters said. Light rain is expected on Saturday.

The warmer than normal temperatures this week are the result of a shift of the jet stream, a vast current of air three miles above the earth's surface, the weather service said. The jet stream, which normally flows southward from Canada bringing cooler air, is farther north than it usually is at this time of year, a weather service spokesman said. It is preventing the cold air from penetrating the mid-Atlantic region, including the Washington area.

Yesterday, Washington's workers, college students on spring break and tourists loosened shirt collars and threw off jackets as they found ways to revel in the warmer temperatures.

At West Potomac Park, Renee Middhe and John Brownlow reclined on a carpet of grass, seemingly oblivious to others jogging, biking, and playing tennis and soccer nearby.

"This weather is fantastic," said Brownlow, 20, who with Middhe was munching on a vegetarian picnic. "It helps loosen you up and gives you the feel of spring in your blood." A native of Orlando, Fla., he said yesterday reminded him of home.

Herman McCrea, 26, took yesterday off from his housekeeping job at the International Hotel to wash his new pride--a red '72 Pontiac GT sportscar--at Hains Point. About 25 others were also washing cars there. "The weather makes me feel like partying, gettin' down mingling with the people," he said.