With the “polar vortex” bringing frigid temperatures across the country, going outside isn’t just uncomfortable — it can be downright dangerous.
The temperature will drop to -25 F in Fargo, N.D., -31 F in International Falls, Minn., and -15 F in Indianapolis and Chicago, according to the Associated Press.
Straight temperatures aren’t all that matter. Brave adventurers (or those forced to leave their homes) should really consider wind chill — the temperature it “feels like” outside based on the rate of heat loss from exposed skin, according to the National Weather Service.
In colder temperatures, you shiver to produce heat in your muscles. You’ll also need to pee more. Exposure to cold reduces blood flow to the skin’s surface which also decreased the overall volume that your body can hold. Your body responds by ditching liquid, according to an infographic from the Toronto Sun.
Fingers, toes, ear lobes, or the tip of the nose are the areas most susceptible to frostbite. Your body works hard to keep internal organs and your head warm, and sometimes extremities get left behind.
Usually, when parts of your body get too cold, they turn red and hurt. Symptoms of frostbite, however, include a loss of feeling and lack of colour. Anyone showing signs of hypothermia or frost bite should seek medical attention immediately.
The chart below shows how long you can be exposed to certain temperatures before it will result in frost bite.
For example, a temperature of 0°F and a wind speed of 15 mph creates a wind chill temperature of -19°F. Under these conditions frost bite can occur in just 30 minutes. In some areas of the Northern Plains and Upper Midwest, wind chill reached below negative 60 degrees, according to the NWS, when exposed skin can freeze in just freeze in 10 minutes.
You can, however, survive a winter scenario like this. Check out these tips — like wearing mittens instead of gloves.
Extremely cold temperature can also cause hypothermia, when the body’s temperature dips below 95 degrees Fahrenheit. Warning signs include uncontrollable shivering, memory loss, disorientation, incoherence, slurred speech, drowsiness, and obvious exhaustion, according to the NWS.
Surprisingly, hypothermia can occur at any temperature lower than normal body temperature. Factors like body fat, age, alcohol consumption, and especially wetness can affect how long hypothermia takes to strike.
If you fall into water, the situation becomes drastically more dangerous.
For example, in water 32.5 degrees Fahrenheit or colder, you might not survive more than 15-to-45 minutes. You’ll undergo shock within the first two minutes and some functional disability before 30 minutes, according to the United States Coast Guard.
Check out this chart from the Personal Floatation Device Manufacturers Association:
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