I have recognized rainfall at a distance of a
couple of miles under the right conditions (across
a lake or in an open field in flat terrain). I've
never seen snow falling at that distance, though
perhaps that's because I don't spend enough time
outdoors in the winter.

Flying in the winter in the Midwest I've seen snow squalls from quite a
ways off. They're quite similar to summertime thunderstorms, in that
they are isolated enough so that you can easily fly around them.

But I don't think you can tell a snow cloud by looking at it. Although
winter clouds DO look different than summer clouds, not all of them
produce snow.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"