This morning, we had to do a spot inventory check of some of our products at a cold storage warehouse. We spent about 20-30 minutes in -20*F temperature. I could have been better prepared. This is what I wore:

ECWCS parka over a fleece vest over regular clothes, insulated boots, three layer gloves and a baseball cap.

This is what was cold:

My right hand because when I dug a flashlight out of my parka sleeve pocket, I had to take a glove off for about 30 seconds. The hand never recovered. My ears, should have worn a watch cap. My left knee, which still hurts, because it only has 50% of it's cartiledge. I need to figure out what to do about that, maybe some kind of heated wrap for the BOB.

One thing of note, whenever we were near a circulating fan, the temperature drop was extremely noticeable. Had this been outside, with real wind, it would have been much worse.