I shot a lot in snowstorms in Scotland, Peak District and Lake District.
1. Seriously cold / powder snow is best as it tends not to stick to you or the camera and, therefore, not actually "wet" your camera / equipment.
2. If you can, stand with your back to the direction from which the snow is blowing - avoids as much as possiblefrom hitting your lens.
3. Don't go far from shelter, food and drink. Nice photos are one thing, dying falling off a mountain, through ice or getting lost isn't worth the risk.
4. Warm your kit back up to room temperature slowly and don't store when wet.
5. Don't use "Digital Ice" to get dust off negs while scanning as it'll probably remove all of the snow - thinking it's dust.
6. Personally, I'd rather use a tripod than a flash. Snow has movement, it doesn't just hang there frozen (pun not intended) in mid-air.
7. Why not go for Ilford 3200?