Anchored by Jake Tapper, The Lead airs at 4 p.m. ET on CNN.
The latest on national protests. Plus, what went wrong in Yemen rescue attempt?
(CNN) - Throughout this cold blast, CNN has been conducting a grand experiment on the effects of hypothermia on reporters. Two of our guinea pigs today - CNN's Erin McPike in Minneapolis, where temps have hovered around zero all day, and CNN's Ted Rowlands in Chicago, where it's even too cold for polar bears at the zoo.