D.C. police say the cold may have been a factor in two deaths yesterday morning as frigid air came to the Washington area on the coattails of Christmas.

The mercury dropped to a brisk 11 degrees at National Airport at 7 a.m. and crept to 22 degrees by afternoon, 22 degrees short of the normal high for the day.

As a warm front moved in late last night, the temperature rose to 24.

Two men who a police spokesman said "appeared to be homeless" were found in the District -- one at 5 a.m. at North Capitol Street and Florida Avenue NW and the other at 9:40 a.m. at 18th Street and Massachusetts Avenue SE.

Police said late yesterday that the men, the first about age 70 and the second in his thirties, had not been identified. Autopsies are scheduled for this morning.

Darryl Heller of the Community for Creative Non-Violence said the risk of death from hypothermia is "an ever-present concern" for homeless people. CCNV's shelter at 425 Second St. NW drew 712 people Christmas night, Heller said, compared with an average of 450 in warm weather.

"Each night, it's been steadily increasing because of the weather. I expect it to be at least [as full] as last night, if not more," he said late yesterday.

Forecasters said the wintry weather, caused by a cold air mass that drifted down from Canada on Christmas, would not last long. The warm front should thaw the eastern part of the country today, they said, and temperatures in the Washington area are expected to rise into the 40s.

Although it wasn't cold enough to shatter a record -- the low for Dec. 26, in 1935, was 4 degrees, it was cold enough to surprise even the most seasoned of weather buffs.

"Good grief, it was the coldest day since Jan. 22" -- the day after inaugural proceedings succumbed to a temperature of 4 degrees below zero -- said National Weather Service forecaster Scott Prosise. "And it's the coldest so far this winter."

Around the Washington area, the chill lured customers into downtown fur stores but kept a vendor of wool hats and earmuffs huddled in his van. It was a good day for sellers of space heaters, not quite as bright if your product was ice cream.

It was a day like any other for the Intrepid Jogger.

Karen Menichelli of Arlington stopped mid-stride on Wilson Boulevard in Clarendon and carefully removed the layers between her ear and the air: first a pair of furry earmuffs, then the rubber plug of a pocket tape player. "I didn't realize how cold it was until about a mile down that way I saw a temperature thing. It said 22," she said. "But I've only gone about three miles, so I haven't frozen yet."

Menichelli said the holidays gave her a reason not to break her routine of daily three- to four-mile runs. "I ate a very big Christmas meal," she explained.

At Hechinger's in Langley Park, the cold boosted sales of space heaters and bundled wood. But the hottest items of the day were Christmas ornaments marked down a cool 40 percent, said assistant manager Lynne Haines.

Is cold weather good for fur sales? "Obviously," said Randolph Garfield, vice president of Rosendorf-Evans furriers on K Street NW, as he glanced up from an order slip.

A chandelier shone on furry sleeves and lapels the color of new snow. A saleswoman hurried toward some customers. "We're a little busy for interviews; come back in July," she said.

Garfield said drops in temperature don't affect customers' preferences for dark or light-colored furs, short or long ones. "They get the type of coat they wanted whether it's warm or it's cold out. And 80 percent of what they want is mink."

Outside, on K Street, the air had teeth. Vendor Rafael Vidarte hunkered over a steaming cup of coffee in a toast-colored Toyota van, watching his display of earmuffs, gloves and berets through a streaked window. "I've sold three pairs of earmuffs," he said. "The problem is, there are not too many people in town."

At Union Station, 23 taxis idled by a nearly empty sidewalk.

"It's kind of slow today, because a lot of people are still away," said Jim Douglas, whose Diamond cab was fourth in line. He had been there 40 minutes and had managed to nose the taxi into a spot of sunshine. "I usually keep moving, but the sun feels good sitting here. I feel sleepy and lazy," he said.

It was a slow day at Bob's Famous Ice Cream on Massachusetts Avenue NE, where a lone clerk watched an empty store. People do eat ice cream in cold weather, he insisted. "We're running eggnog ice cream, because of Christmas, so that's popular . . . . They eat ice cream with hot fudge, hot apple-cinnamon sauce. But they wouldn't usually go outside with it in their hands."

Across the river in Arlington, Lester Gilbert's lunch cart sales proved it is never too chilly for chili. Gilbert, a wool hat tugged over his forehead and a hooded blue sweatshirt zipped to his chin, pulled off one layer of gloves to pile a hotdog with all the trimmings: first catsup, then mustard, then relish, chili and sauerkraut. "Things are a little slow, but the chili dogs have been going really well. I guess people are still recovering; they're still stuffed from yesterday."

Back in the District, at least one merchant seemed to have jumped the seasonal gun. The windows of Ann Taylor were filled with polo shirts in pastels and clothes in sprightly floral prints. But the store was bereft of customers, and a small sign of explanation was taped to the door: "Sorry . . . we are closed due to the extreme cold. We'll reopen Friday at 10 a.m."