You can see in the image how the "polar vortex" has ripped apart and spread Arctic air down toward the equator.
The purples are where the air is colder than average, while the orange and red are warmer than average, as you can see in the scale to the right. You can see one purple blob sitting over the U.S. East Coast and the other on the other side of the planet, above parts of Russia.
The image was originally tweeted by Stefan Rahmstorf. It was created using The Climate Reanalyzer, which you can play with online. This representation came from the "air temperature anomaly" setting, which means the temperatures depicted are how different this current weather is from the average.
Here's the other side of the globe:
