Robert F. Bukaty / AP

A barge motors through arctic sea-smoke on its way out of Portland Harbor, where the temperature at sunrise was about minus 5 degrees, Thursday, in Portland, Maine. Arctic air kept a cold blanket of misery over the Northeast Thursday as the region experienced the kind of temperatures that have left the Upper Midwest shivering for days. Continue reading.

• Slideshow: Winter's frozen splendor
• You know it's cold when ski resorts close the mountain
• Follow @NBCNewsPictures on Twitter

Slideshow: Deep Freeze

John Gress / Reuters

Arctic air has descended over the Northeast as the region experiences the kind of temperatures that have left the Upper Midwest shivering for days.

Launch slideshow