Mike Rapoport wrote:

It goes the other way. You would have to take quite a bit of energy out of
the partially melted snowflake to refreeze it. Snow is fully crystalized.
If it is melting than the temp has to be above freezing. It the temp is
above freezing then nothing can stick. It is impossible for snow freeze
onto an airplane above 0C SAT. The temp must be below freezing and the
stuff sticking to your wing is almost certainly supercolled water from cloud
droplets.

Yes, I agree and didn't say anything different. My point was it may be
possible that the frozen part of the flake could absorb enough energy
from the liquid part to partially refreeze it.

I don't agree that nothing can stick above freezing. Snow will stick to
a wet surface much easier than a dry surface. If the wing is damp from
the wet snow, it may well attract "dry" snow that is impinging.

As I said earlier, I make no claim to have an explanation for this.
I've simply observed it many times in winter in PA. You can believe it
or not, your choice.


Matt