so yeah, there is hopefully some blood in your hands. Maybe.
Today I was out for two hours and it was kinda cold. So when I got back to home my hands hurt a lot. Why?
Well you could say that there is blood in your hands, and well it would be true.
The reason for it is similar to why you need to go to toilet when your legs get cold. Body is trying to save some heat by keeping it close to other heat and also save the important parts of body (your organs). To do it, it must make all your veins and various tubes in limbs thinner. At the same time some of those liquids have to go somewhere, so they go up to your important body parts and eventually you also need to pee.
When you get back from outside, your body feels that there is much more heat so the tubes can be expanded again. This also triggers pain receptors. So rapid heating of your body causes the pain that you can feel in winter.
When you dring alcohol, the body thinks that it is warm around so the tubes are expanded even when it is freezing. Now the blood runs down to your limbs which are feeling pretty good but they lose heat very quickly since when you pull something on bigger area it cools faster. This may even kill you when it is very cold outside.