40 F above ? not minus 40? That's a typical early morning/evening here it rises to 50F by the afternoon, .
just 10 minutes? long under wear , pants a couple sweat shirts the hoodie and a crew neck ..
and my Parka .. work fine some cheap ski gloves in the pocket of the parka.. thick socks and boots ..
going inside again any sweat absorbed in the cotton sweat shirt dries fast enough.. no 'cotton kills' warnings apply..
you are not staying out hunting ducks in a blind all day....
Just 10 minutes..
.....