Staying healthy in extreme temperatures can be a challenge, especially if one’s health is already compromised.

Dr. Jay Selman, the chief of neurology at Blythedale Children's Hospital, says in a polar vortex, dress in layers and cover up exposed skin to avoid frostbite, which can set in a matter of minutes.

“For babies and small children, the head is relatively large compared to the rest of the body, and it can act as a reverse radiator and you can lose heat, so making sure they have one or two hats on,” he says.

Doctors also suggest avoiding large crowds to prevent the spread of germs and if you can't stay at home, be smart with how long you're going to be outside.

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