why is snow so slow?

[blitzskier]

got a couple runs in today, being spring the snow is thawing out and has strange tendancie. My question is when on a north slope in the sun, the skiing is fairly fast, then all of a sudden I pass under a shadow of a Pine tree, and whooa baby its like I hitting the brakes. I would guess the snow is colder in the shade and would it not be faster than the slush?
?what is going on here at the scientific level?

I am skiing the 145 Altai Hok, so maybe the skin is grippy, I do wax the skin.

[phoenix]

I think you will get more replies on the regular talk forum.

[Montana St Alum]

It's the opposite, without skins. Fast in the shade, over the handlebars in the sun.

[blitzskier]

thats what i thought, i'll have to bring out a waxless xc ski and try it.

[Stephen]

The moisture in the skins from the warm, wet snow may be freezing in the cold snow in the shade and causing drag.

[blitzskier]

well that make more sense, thanks for the input

[Gusaroo]

My guess/hypothesis is that when a ski is running nicely it is running on a hydrodynamic film of water, caused by the friction between the snow and the wax/base. The colder snow in the shadows did not melt into a water film.
Just an idea for discussion.