Do not push the limits of your physical capabilities. Minor altitude illness symptoms can occasionally become life threatening. At high altitude the ultraviolet rays from the sun are more intense and, therefore, more damaging. Even when it is cludy, the risk of sunburn is extreme. The air temperature falls about three degrees Fahrenheit for every 1000 feet of elevation gain, therefore, temperatures in the high country can drop rapidly.
Warning signs are confusion, difficulty speaking, irritability and loss of coordination.
Bring along extra clothes, drink and eat sufficiently and watch for warning signs in each other. If in doubt, stop, warm up, and take fluid and food, and if necessary send for help. Frostbite is caused by cold exposure, resulting in ice crystals forming in the skin. It frequently occurs in the extremities, specifically the nose, ears, fingers and toes. The skin becomes numb, firm and yellowish white in color.