My dog has the same, more of a tight coat.
I never use a jacket except for days where I have to walk the dog and it's freezing rain or something really bad like that. I did get one that is water resistant and has thin layer of insulation. I have also used it when it's been extremely cold and I've had her out at a workshop and she has to sit in a cold car for a number of hours in her crate, she seemed comfortable.
This is the one she has, I think RC West Coast Rain Wear, Black - 12
I've only used it a couple of times though
If it's just snow, she doesn't need a coat, I think they really do like the colder weather rather than the warmer months.
I tried boots on her paws because when it's bitterly cold, she was limping (not from salt, just from the cold), but she will not wear them (I can't say I blame her), so unfortunately, she just has to gimp around while she does her business.
I think there's a product you can put on their paws, to help protect them, but I can't remember what it's called.