The restaurant at the top of the mountain is packed, though the queues are not for tartiflette or omelette savoyarde but for the distinctly un-haute cuisine of haggis and neeps and tatties.

In the shop by the funicular railway, Loch Ness Monster books and goat’s- milk soap from a local crofter are on sale next to ski goggles and thermal leggings. The weather forecast — “Some buffeting on higher slopes” — sounds particularly Scottish, while the signs for the “Cairngorm Poo Project”, an initiative to cut human waste left by walkers, would be hard to imagine in Courchevel or Val d’Isère.

Only a year after experiencing its worst season, the CairnGorm Mountain resort near Aviemore is defying the doomsayers of global warming and predictions of its demise.

The car park is full and the slopes busy. When the sun comes out, it is almost warm. After several weeks of decent snowfalls, the spring skiing conditions are, according to everyone who knows, the best in living memory. The resort has even run out of up-to-date piste maps, and has had to advertise for extra staff because many of its seasonal workers have already left.

The snow in Scotland is so good that at least two of its five resorts are expecting to extend the season into May. It may be just temporary, but for the moment the Great British Ski Resort is back in business.

“Yesterday I had a business appointment at the bank in the morning, but after work I was ski touring until 8 in the evening,” says Bob Kinnair, 54, chief executive of CairnGorm and a former head of the British Association of Ski Instructors.

“It was just me and a mountain hare. I’ve been skiing here for 30 years but these are the best spring conditions I can remember.” He adds: “It’s an extraordinary position for Scottish skiing to be in heading for the end of April in this century. We were open for skiing on December 1 and we’re expecting to be open on May 1, which will take us into our sixth month.”

Despite the snow cover — at least a metre has fallen at the top (altitude 3,600ft, or 1,097m) — skiing in Scotland remains a unique experience. The piste names — Over Yonder, M2 and Side Slope — have a prosaic charm of their own. Bright orange signs highlight rocks and streams, while fences at the side of slopes prevent the snow from being blown too far by strong winds.

This week, after a fresh dusting of snow on Tuesday, conditions remained surprisingly good. Despite a fair bit of “buffeting” (just 30mph when The Times visited — a good day) and sub-zero temperatures, there was fresh powder to be had in the bowls and gullies surrounding the 37km of groomed runs. Only a few weeks ago it was possible to ski all the way down to the lower car park, an event so rare that it was described as a “once-in-a- generation experience”.

CairnGorm’s target of 51,000 skier days was passed two weeks ago, and it should now comfortably exceed 60,000, with many travelling up from England.

Although this is still nothing like the 150,000-200,000 skier days enjoyed by the resort in its prime 30 years ago, it represents a dramatic increase on last year’s 38,000.

The improvement in conditions means that CairnGorm can expect to make a small profit this year, though most of that money will be reinvested in the resort infrastructure and used to service bank overdrafts. After just about breaking even for half a dozen years, the resort made a loss of £200,000 last year, raising serious questions about its future and the viability of Scottish skiing.

Scotland’s four other resorts have all enjoyed good conditions this year. Iain Hayes, 22, from Aviemore, who has been skiing in Scotland since he was 3, said yesterday: “These are the best conditions I can remember for ten years. The cover is incredible. It’s opened up the whole mountain.”