Hey, did you know it's cold in the Midwest today? Like, really cold. It's been cold all weekend all across the country, sure, but let's have some sympathy for our friends in the middle of the country this morning.

They're seeing high temperatures that won't break zero. Let's go over that again: some high temperatures in the United States are in the negatives today. Damn.

Source: The Weather Channel

These, my friends, are dangerous temperatures. Not only are they some of the coldest temperatures in decades, but they're coming with strong winds, making for truly hazardous conditions. We're talking frostbite, folks. Even a few minutes outside in the Midwest today could lead to frostbite. Take a look at this chart from the National Weather Service: 

Source: National Weather Service 

Take that -10 degree high temperature in Illinois today. With a 5 MPH wind, calm by any standard, the temperature feels more like -22 degrees and it takes only 30 minutes of exposure to contract frostbite. Thankfully, the Packers game was yesterday.

Extremities like fingers, toes, and ears are particularly at risk. So, for the love of god, if you're in the Midwest, wear a hat and pair of mittens today.

What's causing all this cold? I present to you: the polar vortex.

Air from the North Pole is being pulled farther south than usual, which means the U.S. is feeling some arctic temperatures it doesn't usually experience.

And if you think it's just the Midwest that has to worry about this, think again. While the Northeast might feel pretty balmy today, the cold is headed our way. Tuesday will see New York and the rest of the East Coast hit single digit temperatures.

So really, everybody should pay attention to that frostbite chart. All hail, winter.