Long, thermal underwear. 50 F to 14 F The most dangerous. Wide temperature variations from melting during the day to freezing at night makes proper dressing difficult, and important. Damp conditions from melting snow or rain makes keeping dry difficult. F Ground is frozen and snow is dry and crystallized.
Strong winds cause the most concern with keeping warm.
Extra clothing layers and wind-proof outer garments should be added. Many materials change physical properties, becoming brittle. Only for the most experienced campers. The body's process for maintaining an even temperature. The arms and legs are used as a radiator to remove excess heat from the body.