There is, 'tis true, a sort of long sliding scale between dry powdery snow, via wet sticky snow, via supercooled water droplets which cause icing, to good old fashioned rain.
Some of it (around the wet sticky snow/supercooled water bit of the line) that will build up on leading edges and (particularly with wet snow windshields). Some of it is no more than an irritant and obstruction to visibility (dry snow, rain). A sub-zero airframe on the other hand will collect rain and wet snow quite effectively.
Accurate prediction of what you are going to hit, and whether it'll stick is not very easy so, personally, I would (particularly in the UK which tends to hover around freezing so wet snow is reasonably likely) not assume that snow won't build up.
G