A fine hill
Although this is a hairy story, I still recommend a winter ascent of Ben Mac Dui.
Started out on a Saturday morning taking the bus from Aviemore to the Cairn Gorm ski station. Stormy conditions were forecast, with very high winds. There was little or no snow in Aviemore, but it lay thick at the ski station. We began walking but didn't go to the summit of Cairn Gorm itself. Instead we followed a line of cairns around the mountain to the Cairn Gorm plateau. It was very cloudy, and soon we were almost in whiteout conditions even though there was no snow falling. Crossed the plateau using compass and map but there was nothing to take a bearing from. No rocks came up through the snow and there was no horizon visible, just a greyish white mass in all directions. The GPS was needed to get our position on the map. After a couple of hours, we finally got to the summit of Ben Mac Dui, but our exuberence was dampened by the rising wind and fading light. It was 4 pm, and we decided to camp about 50 m down from the summit on the lee-side of the mountain, in the shelter of a large boulder.
We piled up walls of snow to make wind blocks. This would save the tent, but we were still feeling the effects of the savage gusts which swirled around the boulder and over the walls hitting the tent from all directions. The wind strengthened relentlessly all night. Some gusts were so strong that tiny flakes of snow were being forced through the flysheet and belly of the tent and were falling onto our sleeping bags. I've never heard of that. We had to scream at each other to be heard. I tried sticking my head out the tent, but couldn't even open my eyes in the blizzard. We stayed in that spot for two nights. Scotland was suffering its worst storm in years, trees were being blown down in Glasgow. 2 foot of snow fell around our tent in 36 hours, and gusts of over 120 mph were recorded at the Cairn Gorm weather station. We woke up after our second night to the sound of pure silence. Relief at last. We got out of what was now a hole in the ground with our tent in it. The snow walls we built were buried. Luckily, when we stepped onto the new snow, we did not sink in, the crampons just bit into the icy surface. We lost some gear entombed in the snow and ice, but that was ok. We didn't expect we would need our snow shovel again. With our ice axes we hacked out the tent and rucksacks. We made our way back to the summit of Ben Mac Dui, and from there back to the Cairn Gorm ski station.
To cap it off we read in the Scotsman the next day about a major mountain rescue effort to save a man who was holed up in a stone bothy in the Cairn Gorms during the storm. The bothy was in a valley, over 3,000 ft below us!