SL, among other layers including a 200 wt Polartec 1/4 zip sweater, I carry a down or synthetic sweater, as well as a goretex wind/rain jacket.

Here's a good thread about layering:

https://www.24hourcampfire.com/ubbt...13019767/re-clothes-for-elk#Post13019767


“Perfection is Achieved Not When There Is Nothing More to Add, But When There Is Nothing Left to Take Away” Antoine de Saint-Exupery