What is meaning that you want to express?
a1) I will go in summer to the Alps.
b1) I know that in summer there is less snow than in winter.
You only expressed:
a2) I will go to the Alps (nothing is said about when)
b2) I know that in summer there is less snow than in winter.
I you want to express (a1) and (b2) here is the correct constructon:
Andro` nelle Alpi d'estate, anche se in estate c'e` meno neve che in inverno.
The verb is at the present as you are comparing a situation that repeats in time
from year to year.
Andro` nelle Alpi quest'estate, anche se ci sara` meno neve che in inverno.