Technically, Antarctica is largely considered a desert based on the amount of precipitation it gets through the average year. The temps can still be higher, but in years where Antarctica receives an above normal amount of snow, there may not be enough time above freezing temperatures in the warm part of the year to melt off all the snow accumulated during the colder months.
Sometimes, the Devil is in the details, not the headline.
Northernmost Canada is also considered a desert. If, for example, the areas north of the Arctic Circle were to start receiving an extra 20 ft of snow each winter, there's a good chance that would be the recipe for initiating another round of continental glaciation. We intuitively want to link more cold weather with formation of glaciers. However, the actual formula governing glaciation only requires one to just get more snow than what can melt in that areas warm season.