The weather lately seems to bear a striking resemblance to the Washington Redskins: Hot one week, cold the next. Yesterday, both were hot.

But be warned, those who enjoyed the Redskins' victory yesterday and the balmy reprieve of mid-sixties temperatures. Today, forecasters expect the weather to take a decidedly arctic dip back into the thirties.

"It is unusual," said Accu-Weather meteorologist Paul Yeager, referring to the local climate, not football. "It has been a very changeable pattern."

It doesn't take a satellite to tell that.

In the last week, the Washington area has gone from highs of 71 degrees on Dec. 23 and 65 degrees on Christmas Eve, to a low of 23 degrees accompanied by 3 to 5 inches of snow two days after Christmas, and back up to a record-breaking 70 degrees yesterday.

Area residents didn't quite seem to know what to make of it. Many traveled around with heavy coats draped over their arms yesterday, either unaware of the brief warming trend when they walked out the front door or unwilling to trust it.

"We went out today and bought a heater and then it was 70 degrees today, so we don't know if we invested our money wisely or not," said Bill Rada, 45, a U.S. Foreign Service officer who lives in Arlington.

Told that the mercury is supposed to drop as much as 30 degrees by today, he sighed in relief. "We bought the right thing then."

Rada was one of dozens of area residents who took advantage of the weather to venture out to Gravelly Point on the Potomac River to watch airplanes cruise just yards overhead and land at National Airport. Having spent most of the last 10 years overseas in Latin and South American countries, Rada's two daughters, Elizabeth, 9, and Jessica, 6, have been a little surprised at Washington weather.

"This was the first snow they've seen in their lives," Rada said of the Thursday night snowstorm.

By yesterday, nearly all evidence of that paralyzing snow was long gone. While the overcast skies and blustery winds didn't encourage picnics along the Tidal Basin, many in the Washington area took advantage while they could. There were museum visitors aplenty, as well as joggers in shorts, bikers in spandex, dog-walkers in sweats and even the occasional sail-boarders in wet suits.

"It's gorgeous," said Jose Moreno, 35, who lives in Falls Church and works for an asbestos removal company. Wearing a short-sleeve, green, flower-print shirt that seemed more appropriate on a Caribbean beach, Moreno brought his 4-year-old son, Josue, to Gravelly Point to watch the jets.

"It's like a yo-yo around here," he said. "Up and down, up and down."

Paul Harrington, though, professed the nonchalance of an area veteran. "It didn't surprise me that much, actually," said Harrington, a Massachusetts native who was riding his bicycle along the Mount Vernon Bike Trail. "I've been down here since '77 and you kind of expect it. It seems to do this a lot."

Besides, he said, he had a hint of what was to come Saturday night. "We opened the window to cool the place off and it only got warmer."

His companion, Deborah Pokorney, was trying out her new bike, but was certain she will have more rides this winter. "I don't think it'll be the last opportunity," she said.

She may be right. For the time being, though, the professionals advised wearing overcoats rather than jogging shorts. By sunrise today, a cold weather front will arrive in the area and depress temperatures through New Year's Day.

How can it move from snowy to balmy and back again almost overnight? "This is winter, remember," said Andy Stern of the National Weather Service. "We can have very fast-moving weather systems."

That's what happened last week when the arctic air mass from Canada rippled over the mountains from the West Coast and arrived in the east in time for moisture to arrive from the tropics, Stern said. Then a warm weather pattern from the Gulf Stream tried to move northward, he added, but ended up trapping the cold weather for a day before finally blowing out the cold air yesterday.

According to Stern, there is a 55 percent to 60 percent chance of above-normal temperatures during January. "But," he warned, "that doesn't mean you can't have two snowstorms in between."