SALT LAKE CITY — A polar vortex has washed over much of the United States in a cold snap.

We’re seeing temperatures like minus 23. BBC News called the cold temperatures “once-in-a-generation.”

So, yeah. It’s pretty cold.

But what does it feel like? It’s one thing for us to see these temperatures pop up on our iPhone weather apps. It’s another thing to feel it.

Well, data from the last few years can help us understand the chilly temps from the polar vortex and snow squalls seen throughout the country this week.

In 2014, the National Weather Service put together a chart that explained how long you can last in extreme cold before you suffer from frostbite.

As you can see, you can only last in minus 23 degrees for about 30 minutes before you suffer frostbite.

More feelings: But it’s not just the temperature to consider.

  • “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,” according to Business Insider.
  • “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.”