What is the lowest temperature would you...
What is the lowest temperature would you recommend for this jacket?
Usually with baselayers a wind stopper softshell, I feel comfortable in the high 50's /low 60's. You might feel cold if you go lower than that without more layers. This of course is if you're static. If you're doing a high output activity such as hiking or mountaineering, you could go much lower. Just keep moving.