When the temperature drops, it's no time to be outside unprepared to deal with the frigid conditions.
Otherwise, it can mean not only being cold and miserable, but becoming a victim of frostbite, according to a Geisinger Medical Center emergency physician.
"Frostbite is basically damage to the soft tissues of the skin and underlying tissues of the body," explained Dr. Douglas Kupas.
Hank Wade, at top, is bundled up as he clears snow from a sidewalk Jan. 6 in Lyndhurst, Ohio, with temperatures of around zero with possible wind chill factors of 40 below zero prompting a rare wind chill warning, which means frostbite could affect exposed skin within 10 minutes outside. Above is Geisinger Medical Center emergency room physician Dr. Douglas Cupas, who was interviewed for this article.
It occurs, he said, as a result of over-exposure to the cold, often affecting toes, ears, hands and feet and other body parts farthest from the central circulation system.
It's in these body parts that can be found small blood vessels.
In its initial stages, frostbite usually is apparent with the skin turning white.
"And it gets very painful," Kupas said. "A lot of people equate it to a burn injury. Nerves are very sensitive to the pain of this."
Anyone experiencing frostbite should get inside to a warm place and remove any wet clothing.
Steps should be taken to warm up the frostbitten area.
For example, a good measure to take if hands are affected is to place them in one's armpits.
However, precautions must be taken in warming up an affected area.
"You have to be careful not to injure yourself, particularly if you are numb," Kupas said. "You lose feeling and you might put too much heat on the affected area."
Never rub the spot where frostbite occurs, he added.
Persons with more serious cases of frostbite should go quickly to an emergency room.
In its severest form, frostbite of a body part can lead to its amputation. That's because tissue is killed as the result of not receiving any blood flow.
Many people, Kupas said, have experienced frostnip, a mild form of frostbite.
Frostnip symptoms include skin that becomes pale, cold and numb while deeper tissues remain unharmed.
Kupas said Geisinger sees few cases of frostbite.
There seems to exist no precise cold temperature for when frostbite can begin to occur.
"Everyone likes a temp number and how long you have to be out in it (cold)," he said. "There is no magic number."
Infants and the elderly, those with diabetes or with diseases linked to poor circulation are more susceptible to frostbite.
The good news is frostbite can be prevented.
"If you cover all those important areas (while in the cold) and make sure they stay warm, you will last longer," Kupas said.
Staying well hydrated can help prevent frostbite as well.
But alcoholic beverages should not be used to stay hydrated, Kupas noted.
For one, alcohol misleads a person into a feeling of warmth.
Alcohol dilates the peripheral blood vessels near the skin, which means more blood and heat flows to these vessels.
That takes blood and heat away from the body's core.