It is true that it is a mountain. Still, the elevation is not high and you would not see any snow there, on the other side because in winter most of the days there is a little bit of breeze so you would experience a very clear view of Montserrat mountain, the monastery and even in some days the Pyrenees. So one recommendation for a day trip from Barcelona in winter, November, or December is
half day tour Montserrat from Barcelona, .