It is 7 a.m. and I am trying to keep my balance on the icy path that leads to the Tasman Hut's precarious outhouse. A slip here would mean a 400-foot fall to the glacier below, but even with the childhood rhyme "red sky at morning, sailor take warning" filling my mind, I can't take my eyes off Mount Cook.

Clinging to a rock knife-edge above the glacier, the Tasman Hut commands what has to be one of this planet's most spectacular alpine views. With Mounts Cook, Tasman and Douglas soaring to more than 10,000 feet along New Zealand's Main Divide, I know I should be thinking major thoughts about man, God and the presence of both in high mountains. But here in the Southern Alps, approaching low pressure is heralded by the appearance of flame-colored lenticular clouds above Cook's 12,349-foot summit, and in the past hour any fine philosophy has succumbed to a growing anxiety.

One look at the cables strung across the hut's corrugated steel roof is enough to tell you why. I know I should be reassured by the fact that the Tasman Hut's subfloor is weighted with 20 tons of ballast, but park geologists believe that the supporting rock is so badly eroded that the hut is in some danger of crashing to the glacier below. Remote, they say, but given a large enough storm, entirely possible.

Much of the reason for their concern is that storms do not appear as much as explode over Mount Cook. Between the Southern Alps and Tierra del Fuego 11,500 miles due west, there is no land to slow the rush of wind and wave. When a major storm crosses New Zealand, the resulting collision approximates an immovable object acted upon by unlimited force. Known as Aorangi or "Cloud Piercer" to the native Maori, during winter Mount Cook -- and the rest of the Main Divide, of which it is the highest peak -- experiences some of the harshest conditions on Earth: 150-mile-an-hour-plus winds and 250 feet of snow per year, conditions that routinely strand climbers, at times for weeks.

In fact it was for shelter against the South Island's powerful storms that the first huts were built, at the turn of the century. Though once the exclusive domain of climbers, these upper ice fields (and the huts themselves) have been opened to skiers by Mount Cook Airline's ski planes. Two friends and I had come to New Zealand to spend an August week on these ice fields, a week in which we would cover 60 miles on two glaciers, alternately skiing and hiking, seeking out three of the huts for our nighttime shelter.

Although they cover an area larger than the Austrian and Swiss Alps combined, the Southern Alps of New Zealand are still virtually undiscovered. Partly because of the isolation, partly because of the rare combination of towering peaks, moving ice, green forests and sunlit seas and partly because of the excellent winter snow, Mount Cook's glaciers offer a startling contrast to lift-assisted skiing. On the glaciers, there are no lift lines, no ticket checkers, no amplified rock or bare rock, no moguls or ski patrols ... no people.

If New Zealand seems like a long way to go in search of solitude, the skiing in the Southern Alps -- where in places the glaciers are two miles wide and a mile deep -- can be the best in the world.

Two days after we checked into Mount Cook's century-old Hermitage Hotel, the forecast called for a day of stable air before the next storm reached the west coast, and that morning we booked a flight up to the Cornice Wall above the Tasman Hut. I cinched down on my shoulder harness and watched the plane crab into the wind toward an uphill, crevasse-free section of the glacier. The starboard wing dipped, I heard the engine throttle back, the glacier rose to meet us and we were down, the alloy skis banging through the wind-blown crust. A moment later skis, packs and poles were unceremoniously tossed out and, with the wind now behind it, the plane started a long downhill run before finally lifting off, its wing dipping in farewell.

Our guide, Kevin, a South Islander, shouldered his 60-pound pack and studied Mount Cook. Only 26 years old, Kevin is a certified mountain guide, having climbed every major peak in the Main Divide in his teens and early twenties.

Even with a guide, however, exploring the Tasman ice fall is serious business. The same intense pressure that converted the lower valley into an immense rubble pile has tortured the blue ice into huge blocks, crystal spires and sensual curves. Combinations of downhill creep and melting water have sculpted immense caverns, through which the wind alternately groans, whistles and moans. You can stare down into the icy blue maw of a thousand-foot crevasse or stare up an overhanging cliff face and, if time seems to stand still in this other world of vertical ice, the distant rumble of avalanches, the hiss of wind-driven snow and the lengthening shadows deny it.

We strapped on our skis and, following Kevin, started downhill into this icy maze.

Several hours later, glancing at the sun, Kevin suggested we start back. It was just after dark when we climbed down the icy path into the Tasman Hut, a single room dominated by a central table and a long steel-covered bench used for cooking, surrounded by three walls of bunks. After dinner, the evening weather report came crackling over the hut radio: A rapidly moving low-pressure system was expected to bring high winds and snow to the South Island; the first effects would be felt the following morning. When the radio finally grew silent, a sense of isolation eddied through the cold air and stark lantern light.

Early the next morning, shivering above the hut, I watched the red clouds change to a solid cloud bank that descended rapidly toward the Tasman. A heavy wind gust swept the icy path and I retreated back inside the hut. When the wind whistles through the cables and coats the hut's exterior with an icy rime, days are devoted to melting snow, checking equipment, playing cards, reading dog-eared novels and dreaming of tropical beaches.

Fortunately the clouds lifted late that afternoon, allowing us just enough time to climb Hochstetter Dome, where, when we turned back downhill toward the tiny hut below, the powder billowed around our knees.

At 6 that evening the hut radio reported clearing from the west, so we elatedly decided to catch a flight over to the Fox Glacier, on the west side of the Main Divide. The following morning we met our prearranged pickup, and the plane quickly headed west, across the towering peaks.

Five minutes later, we were set down on a broad ice and snow plain beneath the sheer south of Mount Douglas. The plane turned and with a roar lifted off toward the Tasman Sea, and -- with only 72 hours of clear air before the next storm -- we quickly skied downhill to the Pioneer Hut. Located on a rock outcropping on the Fox Ne've', the hut commands incredible views of both the Main Divide and the Tasman Sea, which, under the effect of benevolent high pressure, appeared as calm as an iridescent gold pond.

Kevin explained that because of successive years of heavy snowfall, both the Fox and Franz Josef glaciers have suddenly started advancing. In 1985 and 1986, movement of as much as six feet per day was recorded, compressing the lower sections into shattered ice blocks and yawning crevasses. Now the only way off the Fox is by plane or helicopter. New crevasses have appeared in previously stable areas and there has been an accompanying increase in accidents.

The problem lies not with the crevasses you can see, but those hidden beneath a thin snow cover after a storm. When the surface appears as solid as a city sidewalk, it is frighteningly simple to blunder into one, and the dialogue of the huts is filled not with tales of agonizing falls and dramatic rescues but of unexplained disappearances.

That night the 15-by-20-foot Pioneer Hut offered a warm, if crowded, refuge from the cold winter night. We had been joined by eight others -- two Norwegians, four Kiwis and two other Americans -- and the camaraderie of the small room lent itself to stories and jokes that continued until the gas lantern finally flickered out.

At midmorning the following day we were three miles southeast of the hut, moving across the upper reaches of the glacier. Our goal was the Marcel Col, from which Kevin assured us we would be able to see both east and west coasts of the South Island, as well as Mount Cook's north Linda Face. Though we made good time, it was late afternoon when we finally climbed the last few feet onto the high saddle.

To the east the braided Tasman River Valley emptied into Lake Pukaki and on to the West Coast. Towering larger than life above us was the tremendous Linda Face of Mount Cook, an immense diamond of glacier ice tinted pale gold by the setting sun. The wind was gusting through the narrow pass and the approaching storm's first gray cirrus dominated the western horizon. Darkness would soon be upon us, and I took a final picture as proof we had made it, then carefully followed Kevin down the broad glacier, on our way back to the Pioneer Hut.

In the morning we would ski down the Fox Glacier to the Chancellor Hut and catch a helicopter out beneath the gathering storm. But at that moment, 3,000 vertical feet of untracked powder lay between us and the Pioneer, and we watched Kevin settle into his first turn, unweight and settle into the next. We waited until he stopped far below, then followed beneath towering rock cliffs toward the distant green forest and golden sea.

Andrew Slough is a free-lance writer who lives in Sun Valley, Idaho. WAYS & MEANS

Unless you have extensive mountaineering experience, a guide is essential for skiing the Southern Alps of New Zealand. Guide companies can supply skis, boots, skins (synthetic seal skins, which along with free heel mountaineering bindings allow you to walk up to 10 miles per day in alpine ski boots), poles, sleeping bags, packs and food. They also arrange flights in and out of the mountains, check on the availability of huts, carry rescue equipment and supply encyclopedic insights into life in the huts.

The huts are basic shelters with bunks, mattresses, full cooking facilities (by kerosene), first-aid kits and two-way radios, for contact with national park headquarters. Food must be packed in. Bathroom facilities are located in small sheds adjacent to the huts and are very basic. Hut fees are about $7 per person per night.

Among the guide companies offering ski trips in New Zealand:

Alpine Guides of Mount Cook offers a variety of ski trips, at a variety of prices. A 10-day tour in the Southern Alps, for example, costs about $1,340 per person, including guide, the flight into the mountains, food, hut fees and ski equipment. Other equipment, including extra clothing and sleeping bags, can be rented. For more information: Alpine Guides Mount Cook, Box 20, Mount Cook, New Zealand, phone 834.

Mountain Guides of New Zealand offers heli-skiing and heli-trekking trips, including a multiday trek through the Southern Alps. For information: Mountain Guides of New Zealand, P.O. Box 93, Twizel, New Zealand, phone 737. GETTING THERE: Air New Zealand has nine flights a week from Los Angeles to Auckland, New Zealand (on the North Island). The current round-trip fare from Washington is $996; tickets must be purchased two weeks in advance, and there is a 25 percent cancellation fee. A "Super Pass" allows unlimited stopovers at any of the airline's other destinations, including Tahiti, Fiji and Honolulu. A round-trip Super Pass from Washington to Auckland costs $1,296; there are no restrictions, and the pass is good for one year.

Air New Zealand also flies directly to Christchurch, on the South Island -- a more economical approach for those going to Mount Cook. The current round-trip fare from Washington to Christchurch is $1,046; the ticket must be purchased two weeks in advance, and there are no stopovers. The round-trip air fare from Christchurch to Mount Cook is $167.

Mount Cook Airlines also flies from Auckland to Mount Cook, for $409 round trip. If you are traveling from Auckland, however, a cheaper alternative is to purchase a Kiwi Air Pass, which allows one month unlimited travel on Mount Cook Airlines. The pass, which must be purchased prior to arrival in New Zealand, costs $349 and is available through Air New Zealand or travel agents. INFORMATION: For general information about New Zealand, including accommodations, contact the New Zealand Tourist and Publicity Office, Suite 530, 630 Fifth Ave., New York, N.Y. 10111, (212) 698-4680.