Now, I did go to real lengths to keep my feet as warm as possible with my 45North cycling boots. I made special gators of stretchy outdoor fabric (not waterproof). They fit snug over my ankles. under my tights or leg warmers and over the boots. Idea is to get water to run down inside the fabric past the ankle opening of the boot. Works quite nicely but it is is for temperatures below 40F. (Also keeps much of the cold air out. I am long enough that a gap between leggings and boot tops is a given unless I go custom clothes.)