we will have much more on the upcoming iowa republican caucuses after a short break. we will tell you what a new poll says about the strength of donald trump's support among the state's gop voters. plus, iowa is one of several states dealing with a blast of arctic air that's impacting millions of americans. >> windchill warnings spilling into the northern and central plains as arctic air could get the windchills down to 45 degrees below zero. all of this happening right in time for the iowa caucus, making it one of the coldest on record. we will take the latest look at temperatures and windchills, that's coming up next.