In reply to Russell Lovett:
Think I read somewhere once that the heaviest UK snowfall is between 0-2degC. Also it doesn't need to be above freezing to snow, was this ITV weather..? It doesn't snow much in Antarctica because the humidity is so low, as you move out to the coast this changes so you get more snow.
Snow can fall above freeing because as it starts to melt it cools the air surrounding it by evaporative cooling (I think that's the term). This means you can get snow to about 4-5degC. Hail is denser and falls much more quickly, that's why hail can sometimes fall in a summer storm higher than 5deg.