This entire sequence coming up was supposed to take place in VERY heavy snowfall. The idea is that their vision is pretty limited, which leads to some bickering between the crew. But when it came to actually doing the art, I was afraid that too much snow on the page would obscure the art to a point where it would become hard to tell what was going on. And I figured all that snow might become annoying to look at for several pages at a time. So I lightened it a bit visually for the sequence, although it is a bit heavier than in the other scenes.
The uber-observant might notice that the falling snow is also elongated and moving diagonally. To really capture the feel of the bad weather conditions, I wanted it to look like a driving snow, not a light snowfall. So I tried to give the snow some directionality to get that windy feeling across.