Source (Bluesky)
Superficial (surface) frostbite: This is the second stage of frostbite, and it requires medical treatment. Your skin might feel warm, but the water in your skin is slowly freezing into ice crystals. Your skin contains over 60% water. This can cause a “pins and needles” feeling. In addition, your skin may sting or swell up. After rewarming, you might have painful, spotty patches or purple or blue areas of skin like a bruise. Your skin might start to peel and feel just like a sunburn. You may also get fluid-filled blisters in the area after a day or so.
https://my.clevelandclinic.org/health/diseases/15439-frostbite