Thanks for the tips, Doremus. I need to explore increasing contrast on overcast days, with or without the snow. I'm wondering if exposure should be adjusted when development will be N+1. Increase a stop? Decrease a stop? I'll do some testing and report back.
And here is a tip for exposing the snow: meter the snow, then open up two stops. In zone system parlance, that moves the snow from Zone 5 to Zone 7. I can't think of any situation where someone would want the snow at Zone 5.