On the heels of successive winter storms that brought heavy snow and ice to a wide swath of the United States, another arctic blast tied to the polar vortex will send temperatures plummeting across the country early next week,

A weeklong, polar vortex-related Arctic outbreak rivaling any seen so far this winter is slated to bring frigid conditions to much of the U.S. east of the Rockies next week. Threat level: The Arctic air is likely to send temperatures plunging to at least 30 degrees below average for mid-February across the Midwest and Plains states,