[Azhia]

This JUST IN from my favorite meteorologist on CBC News...

Those in freezing climates should NOT wear water-based foundation during the winter. The water molecules in the product will freeze, causing damage at a cellular level.
Thus, it is advised to wear an oil/creme-based foundation during cold winter months because, like Vaseline which is often smeared on kids' faces before they play in the snow, oil will not freeze and creates an extra moisture barrier.

Many primers contain silicone. If you wish, you can purchase a silicone-based foundation and skip having to apply a 2nd product (separate primer). For photo shoots (self and clients) I definitely use both products for ultimate smoothness; however, for performance and everyday it is probably not that necessary if your skin is in relatively good condition.