My due date is Jan. 2nd and I've read somewhere to just snuggle up the baby in blankets and use a coarsest cover. I might still want to have him in a nice comfy bodysuit sweater.
Our pediatrician just told us to make sure that she had clothing on for the weather (a fleece sleeper is fine), and after buckling her in, add a hat and tuck a blanket over her and she will be fine going from building to car (and vice versa). He said the same for if we were out and about, and she was (in the carseat) attached to the stroller. Said that the cold air was fine on her face, and not to over bundle or she would overheat.
My experience with having a winter baby last year in Maine was that he tended to overheat in his car seat+fleece sleeper+blanket very easily. Especially when we usually weren't outside for long in the cold. We also used the cozy cover to cover his car seat when outside.
In the beginning we did use the fleece sleepers but quickly realized that cotton sleepers with a hat, heavy blanket, and car seat cover was plenty of layers when only outside for a short time. Also the infant car seats tend to keep baby very warm so that's something else to keep in mind.
I have a winter baby. Lol.. we had two snow storms days after my daughter was born. I just dress her in regular clothes (onesies, tights, pants, or footed pjs) and put a nice blanket over her in addition to warming the car. If you use a car seat cover, it recommended to get a "shower cap" style.
Re: Dressing a newborn for Winter after delivery!
We used this cozy cover. The kind that have a layer under baby are not safe to use with car seats. https://www.walmart.com/ip/EVC-Cozy-Cover-Black/17783099
There are lots of one piece sweater, fleece or flannel outfits that are warm. https://m.gap.com/product.html?dn=gp509035002&dv=1&sdkw=cable-knit-one-piece-P509035&kwid=1&referrer=http://www.gap.com/products/cable-knit-one-piece-P509035.jsp?pid=509035002&vid=1&locale=en_US&sdReferer=http://www.gap.com/products/baby-boy-romers.jsp&pid=509035002&sem=false&vid=1
Carters has some too.
We just had cotton one piece full snap outfits with a Muslin blanket covered by that cozy cover. Preemie stayed warm. (We warmed our car up. )
In the beginning we did use the fleece sleepers but quickly realized that cotton sleepers with a hat, heavy blanket, and car seat cover was plenty of layers when only outside for a short time. Also the infant car seats tend to keep baby very warm so that's something else to keep in mind.