POSTED: Monday, January 27, 2014 - 9:00am
UPDATED: Monday, January 27, 2014 - 9:02am
NBC NATIONAL NEWS — An unusual winter weather pattern is driving air from the Arctic Circle south, leaving a large portion of the nation in a deep freeze.
In cities like Chicago, they've closed public schools and modified public transportation due to extreme wind chill warnings.
This is the fourth arctic blast of the season and it's supposed to be the coldest one yet!
The chronic cold is creating a significant propane shortage across the Midwest, leading Wisconsin to become the latest state to declare an energy emergency in advance of more arctic air blasting eastward this week.
Read More: http://nbcnews.to/1e2bJas