Snow Hills provide 1 Production. Snow Hills may be improved with Mines, which makes them vastly more productive than other Snow tiles. All Hills have a +3 Combat Strength modifier, which can strengthen city defenses, as well as protect vulnerable units.
Similar to its flatland variant, Snow (Hills) is a terrible terrain to settle on, as it only comes with 1 Production as every other Hills variant. You should only consider settle on a Snow tile when you are playing as Sweden, grabbing some rare Uranium that you do not already have in your empire or considering building the Amundsen-Scott Research Station. And even that, one Snow city per empire is one more enough! Snow tiles do give extra Culture to the Ice Hockey Rink, but for Canada, Tundra may be bad but is still way better than Snow.
Very picturesque, very invigorating, beloved of skiers and ski jumpers and other fools. Snow on hills is very nice, and a lot of fun ... unless it never melts.