I have flown in snow in the Aztec, and reaching toward the windshield would produce sparks from my fingertips to the near area of the windshield (like those glass globe which spark under your palm).
For readers wishing to understand the issues with aircraft grounding and bonding from a design and maintenance perspective, AC 43.13-1B, Chapter 11-185 is the best starting point:
http://www.faa.gov/documentlibrary/m...ac43.13-1b.pdf
In particular: 11-187 c. "All isolated conducting parts inside and outside the aircraft, having an area greater than 3 [square inches] and a linear dimension over 3 inchs, that are subjected to appreciable electrostatic charging due to participation, fluid, or air in motion, should have a mechanically secure electrical connection to the aircraft structure of sufficient conductivity to dissipate possible static charges."