A frosty breeze skips across an Allegheny mountainside, and as you hike the snow-packed trails of Maryland's lovely Swallow Fals State Park, a shuddering tree mischievously empties a cold cloud of snowflakes into your face. Your companion laughs aloud, and after a moment you join in; and brief as it is, the episode reminds you of winter's infinite pleasures.

You just have to know where to find them.

The Allegheny Mountains to the west of Washington are such a place. A three- to four-hour drive away, they have become a winter playground, where you go to enjoy the season -- not just endure it. Snow (a prerequisite) customarily falls in ample amounts, drawing to the woodlands and slopes parka-clad city folk eager for fun.

Deep Creek Lake, Maryland's largest freshwater lake and one of its most scenic spots, sits in the heart of this nearby Allegheny vacationland at tiny McHenry in western Garrett County. In summer, it is a popular boating and fishing resort. When the snow sweeps in and the lake freezes over, it is transformed into a bustling winter sports center.

About an hour south of Deep Creek Lake, along U.S. Rte. 219, is Canaan Valley near Davis, W. Va. This is another developing winter sports hub that is particularly good for cross-country skiing, but there are tobogganing, sledding and ice skating, too. To the north of Deep Creek Lake, about an hour's drive on Rte. 219, is the Laurel Highlands area of southwestern Pennsylvania at Somerset, offering a third choice of downhill and cross-country skiing facilities.

In either direction, the highway parallels the ridges of the Alleghenies, past round-top mountains and through narrow farming valleys first settled by Revolutionary War veterans. Along this 100-mile or so stretch of road at the headwaters of the Potomac River is some of the loveliest -- and wildest -- countryside in the three states.

Nineteenth-century visitors were so impressed by the region that they dubbed it "The Switzerland of America." An exaggeration, certainly, but you get the idea.

Year-round residents argue that fall, when the leaves are changing, is when the mountains are their grandest. But winter has its own special beauty. Under a blanket of newly-fallen snow, the landscape takes on the cozy, old-fashioned look of a Currier and Ives print.

Rolling corn fields, sprouting only frozen stalks, give way to thickly wooded hills, which, in turn, climb into the gentle mountains beyond. Serpentine roads lead to quaint communities (Oakland and Grantsville in Maryland, among them), rich in the red-brick buildings of their Victorian past. White steepled churches perch on hilltop ridges, and wisps of wood smoke rise from farmhouse chimneys. In the farmyard, rows of cut firewood are stacked high, enough for a prolonged cold spell.

It's a welcoming setting for winter sports, and the recreational possibilities in these mountains have multiplied in recent years. A winter sports fan can plan a weekend or a week-long vacation that includes an inviting mix of out-of-doors activities. But dress warmly, because temperatures average close to freezing at these higher elevations, which rise to 4,000 feet.

Winter comes early to the Alleghenies, where, because of wind patterns from the Great Lakes, the annual snowfall sometimes exceeds 80 to 150 inches on the mountains. The first snow this season, up to eight inches of it, fell the week before Thanksgiving. So there's often a deep snow cover in these mountains when there's no trace of it in Washington.See WINTER, E3, Col. 1 WINTER, From E1

Downhill skiing is the big attraction, drawing the largest crowds. The resorts seem to compete each season in cutting new and more challenging trails and installing the high-speed uphill lifts to serve them. The major ski mountains are Wisp at Deep Creek Lake; Canaan Valley Resort State Park at Canaan Valley; and Seven Springs Mountain Resort and Hidden Valley Resort in the Laurel Highlands.

Snow-making machines supplement the natural stuff, and once it settles on the slopes you really can't tell the difference. To fill a week, a vacationer could stay at one resort and ski the others, or spend a couple of nights at each for more variety.

Excellent cross-country skiing trails meander through state forests and parks and along valley streams near the downhill slopes, and experienced skiers can venture out on their own. In Maryland's Garrett State Forest, a skiable service road, called Snaggy Mountain Road, once was part of McCulloh's Path, a famed east-west Indian trail across the mountains.

Lessons for beginners are available at White Grass Ski Touring Center in Canaan Valley, Blackwater Nordic Learning Center (Blackwater Falls State Park) at Davis and Hidden Valley Ski Touring Center near Somerset.

When the trees in the Alleghenies are heavy with snow, their drooping branches form an archway above the trails like the beckoning entrance to a fantasy world. The view will even make you forget the cold.

Snowmobiles can be rented at Deep Creek Lake, though aboard one of these buzzing machines a woodlands tour is much noisier and far less contemplative. But it's the thrill of motion that entices you and sends you bouncing between the trees. The romantics, however, will sign up for a horse-drawn sleigh ride, available at Deep Creek Lake and the Mt. Timberline vacation-home resort in Canaan Valley.

On Deep Creek Lake, ice skaters vie for space with fans of ice-fishing, a sport for the hardy and the patient who must first cut a hole in ice a foot and a half thick and then, somehow, manage to keep warm while waiting for a bite. Once in a while, when the wind is up, you might even spot a sleek iceboat sweeping past.

And winter's attractions don't end at nightfall. The apre s-ski scene is lively, especially on weekends. Many of the resort lodgings provide heated indoor swimming pools and, even more comforting, the super-heated hot tubs, which melt any lingering chill.

A winter vacation in the Alleghenies may lack the sophistication and big-time glamor of an Aspen or Sun Valley or Snowbird (unless you count ABC-TV's Ted Koppel of "Nightline," who vacations at Deep Creek Lake). Still, lodgings are comfortable, and the dining is surprisingly good.

And there are compensating advantages. The region is both easy to reach and comparatively inexpensive -- ideal for families on a tight budget. Perhaps even more important, the Alleghenies have a friendly, homespun quality. It's something you come to appreciate.

Each of the resort areas has its particular lure. Canaan Valley in West Virginia is adjacent to some of the most rugged mountain country in the mid-Atlantic region, with miles of quiet cross-country trails. The Seven Springs Mountain Resort in Pennsylvania boasts a 10-story high-rise hotel and unriveled apre s-ski facilities, including bowling alley, handball courts, heated pool and a variety of pubs and restaurants.

But Deep Creek, in the very heart of this winterland, seems very special, and that is because of the lake -- 12 miles long but with so many fingers that the tree-rimmed shoreline actually covers 65 miles. It's especially lovely at twilight, after a day spent on the slopes. You sit in your rented condominium apartment, in front of a blazing fire, and watch the lights from other lodgings come twinkling on across its frozen surface.

Wisp ski resort, just outside McHenry, has been carved out of the tree-covered east face of Marsh Mountain, which rises abruptly from Deep Creek Lake to 3,100 feet. As mountains are judged in the West, it is far from dramatic, but among its 16 trails are challenging runs. (Possum -- the longest trail, at two miles -- is one of the easiest.)

Ski resorts bustle with a frantic energy. Athletic young bodies scramble over the landscape, always in a hurry to get up the mountain or back down again. Wisp is no different -- and yet it enjoys a certain serenity because of its lakeside setting. You can find a quiet in the midst of throngs.

Wisp is run by the Helmuth Heise family, parents and offspring, who came to Deep Creek Lake 30 years ago from Pittsburgh to open a summer lodge. But they found that to succeed they needed to fill their rooms in the winter, and Wisp was born. Big money has been invested in snow-making equipment to assure a long skiing season (into late March), and Wisp now ranks with the best of the region's ski mountains.

For next year, the Heises are planning Wisp's largest expansion ever, a multimillion-dollar construction project. They are building 200 guest rooms and convention facilities to add to the present 60-room Village Inn at the foot of the mountain (currently $65 a night for two, with heated pool). And as the skiing crowds grow, there's more acreage on the mountain for new trails.

The Heises also operate Will O' the Wisp, a seven-story condo high-rise about five miles south along the lake shore. Its modern design is in sharp contrast to the more-rustic alpine look of other lake accommodations, but it is a pleasant place to stay.

All the rooms face the lake, and a large indoor swimming pool and hot tub down the hall beckon at day's end. Weekend package rates begin at $105 a day for two, including a $30 credit toward meals in the Four Seasons Dining Room (or a room-only rate beginning at $58 a night). Unlike the condo, the restaurant resembles an alpine lodge. It was built of native stone and lumber cleared from Wisp's skiing trails.

The dining room's view of the lake is great, and the kitchen serves up hearty helpings. For breakfast, the French toast made from thick slices of banana-nut bread is rich and yummy.

While Wisp can make all the snow it needs as long as the weather stays cold, the cross-country trails in the vicinity must rely on natural falls. Fortunately, "between January and February, you can count on snow here," says Bob Browning, the young owner of Deep Creek Outfitters in McHenry, who rents up to 90 sets of cross-country equipment on a busy weekend. (A set of boots, poles and skis goes for $9.85 a day.)

Browning directs skiers to the six miles of groomed and marked trails at New Germany State Park (about a 40-minute drive away) and to less-crowded Herrington Manor State Park (about 20 minutes), also with about six miles of trails. The Allegheny Mountain Race Series for cross-country skiers is held weekends in January and February at various state parks or ski-touring facilities in the region (information: (301) 334-9180).

For noncompetitors, the gentle terrain of Herrington Manor encourages beginners and intermediates, advises the park's manager Gerald Sword. The hills are steeper and more challenging at New Germany, better suited to experienced skiers. First-timers also can try the 2.5 miles of trails laid out on the 18-hole golf course at Wisp (where Browning has a second shop), although lessons are not offered.

In the summer, Browning, whose cluttered store fronts the lake, sells fishing supplies; he continues to do so throughout the winter to ice fishermen. Their biggest need for the season, though, is an awl or other device to cut a hole in the 18-inch-thick ice. The sport seems to be growing in popularity, he says, but slowly. At Deep Creek Lake State Park, on the lake's north side, the park's staff has scheduled ice-fishing demonstrations Jan. 26 and Feb. 9, beginning at 10 a.m.

The winter catch is reported to be good: yellow perch, chain pickerel, walleye and bass. But it is not an activity, Browning says, for people who like their creature comforts. Many regulars outfit themselves with a tent or other wind shield, "but most guys just sit on a bucket" out in the open.

Brown's workday doesn't end when the skiers and fishing addicts disappear indoors. On some weekend nights, he joins a buddy to play bass guitar in a two-piece "basic rock and roll band" at one of Deep Creek Lake's several nightspots. Many of the mountain people own snowmobiles to travel their own property when the snow gets deep, and recreational trails are open in some of the state forests and parks. First-timers can rent these motorized sleds in McHenry from Crystal Waters Marina and try them out on the adjacent 65 fenced-in acres of the Garrett County fairgrounds. The fence keeps the inexperienced from skidding into the lake.

Actually, operating a snowmobile is "simple," says outfitter Charles Ruskey. You squeeze the right grip for power and the left to brake. Open daily, the charge at Crystal Waters is $20 an hour, and a snowmobile seats two.

Two big snowmobile events: The Maryland State Snowmobile Championships are scheduled at the country fairgrounds for Sunday, Feb. 3, beginning at 1 p.m., when racers will compete over an iced oval track. A day earlier, on Feb. 2, the Maryland state park personnel will lead a two-hour tour of Garrett State Forest, beginning at 10 a.m. at Herrington Manor State Park (bring your own snowmobile).

On rented snowmobiles, vacationers with a sense of adventure can join one of Crystal Waters' moonlight trail rides. A snowmobile in the lead points the way, and another follows the group to make sure no one gets lost. The ride lasts an hour, the cost is $30 for two on a sled, and reservations are necessary at (301) 387-5577. A bit eerie, a lot of fun and definitely cold.

Ah, but there's still charm in the old ways. Up the hill a bit from McHenry on Bumble Bee Road, the Jerry Glotfelty family maintains a pair of sleighs and teams of horses for hour-long rides over the 130 acres of their Double G Ranch. Rides are offered daytime and evenings when the snow is right.

The problem can be too much snow as often as too little. Helen Glotfelty recalls a night when the sleigh was carrying a load of city lawyers and bogged down in deep drifts. The horses kept tugging and yanked the tongue from the unyielding sleigh, leaving the party stranded. Everybody had to stumble back on foot.

The Glotfeltys raise registered working horses, and the grain to feed them, but mostly the ranch is for recreation. The family rents horses and offers hay rides in the summer. (Camping hookups are available summer and winter for recreational vehicles.)

The charge for a sleigh ride, over ranch fields and through woodlands, is about $30 for from one to 10 people. The more companions you get to join you, the cheaper the per-person rate. On night trips, the lights at Wisp can be seen in the distance. Reservations at (301) 387-5481, and bring your own blankets.

Before you leave the Deep Creek Lake area, take a few minutes to drive to nearby Swallow Falls State Park. It is anyone's dream of a real-life winter wonderland, where frozen mists from cascading waterfalls decorate the rocky ledges with spectacular icicles.

A forest of snow-draped evergreens greets you at the entrance. From the parking lot, you walk a few hundred yards over a packed trail through the woods to Muddy Creek Falls, at 64 feet Maryland's highest waterfall. The name is unglamorous, but the view is superb.

A wood staircase, slippery in the snow, leads down from the top of the falls to its base, where the creek pours into a narrow canyon. All around you, everything -- the trees, the bushes, the rocks -- is brushed with a frosting of gleaming ice.

It is a unique place, and a small historical marker reveals that others before you thought so, too. In 1918 and again in 1921, a famous industrial trio -- Henry Ford, Harvey Firestone and Thomas Edison -- pitched their summer camp at the falls to enjoy the splendid scenery, and Ford scrubbed his laundry in Muddy Creek.

In the winter, though, watch out for those playful trees. If you're not careful, they'll dump a branch-full of snow down the back of your neck.