Parka (n) - par•ka /ˈpärkə/ : (as defined by Google) a large windproof jacket with a hood, designed to be worn in cold weather
|From Wikipedia, by George R. King|
My parka is from GAP (although for a while I thought it was from Banana Republic, but I made a mistake and told a lot of people that, sorry). It's 100% cotton, and I would consider it a medium weight parka. The purple-brown color isn't my favorite, but it gets the job done. I'd say the medium weight makes it pretty versatile. Even when it's humid outside, I can use this parka to protect myself from the rain. I was able to ride in it without any issues when temperatures were in the fifties. While I know it wouldn't do much in a downpour, it's a useful outer garment, and it's adjustable and easy to layer.
My OOTD, not exact, but close
If you face real arctic temperatures in your area, parkas close to the original design are available as well. Parkas can be a bit less bulky and puffy compared to a winter coat, which is important to me when riding and doing barn work. With that being said, by all means layer up when you head out to the barn, but once you start moving, a simple lined parka can act as a sufficient top layer. Emma also talked about a few upper body layers that can keep you warm in the winter.