Put on this jacket...instantly started heating up in room temp. pair this with a good fleece or boarding sweatshirt and you'll be just fine for the season. It's a little baggy but don't fear, it still is perfectly sized just with a bit of hang so it can go over ur pants and keep snow out when u tighten the drawlstrings located in the hand/side pockets. Their are also and abundant amount of pockets for you to stash your good stuff, just don't tell your mom.
Ya they do run baggy but keepin it ur regular size will be fine. I normally wear a medium too and when i put this on i was like "wait...this isn't that much bigger". It'll be fine for you, especially if you're like me and still have a little growing to do, otherwise it's still good cuz its got drawlstrings in the pockets to help secure it, which is why 686 makes it baggy; so it can go over ur pants and keep snow out.
for the guy below me...i dont think u understand..this is an impact clothing...as in- it absorbs your fall...regardless of whether u can touch your fingers through it, it still sucks up the impact. there's a difference between constantly pushing it with your own force but one quick impact is gonna be a whole lot different..was going on a rail with these and the rail was plastic on the top and wasn't covered in snow so..it was either fall or fall...and the really saved my but when i took a harsh crack on the ass...but yes they do help more than u think
Since I don't snowboard like hardcore (tear up the terrain park or back country) I probably won't have to worry about the zipper around the waist. I am mostly a beginner but I am good enough not to fall down a lot and rip the zip [lol].