Why is it so Cold this Winter if Global Warming is Real?

A lot of people have been suggesting that global warming is a farce because it is so cold this winter.  For example, it recently snowed in Florida.  So global warming can't be real, right?  An interesting, and seemingly plausible, explanation is that the Jetstream has been weakened due to warmer artic air, causing it to bring bone chilling temps further south.  This New York Times article talks about it.

NOAA.jpg