A stunning photo captured by a pilot illustrates just how cold it is in Chicago.

The viral photo, snapped by pilot Hank Cain Tuesday morning, shows the city frozen by the “Polar Vortex.” It was widely circulated after the Weather Channel’s Shawn Reynolds posted the picture to his personal Twitter account.

At the time of publication, it was 4 degrees Fahrenheit in Chicago.

Incredible Viral Photo Shows Just Cold It Is in Chicago

(Image source: Hank Cain via Shawn Reynolds)

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