The following image shows two jet streams in the Northern Hemisphere. The polar jet stream carries cold air. The subtropical jet stream carries warm air. Image courtesy of NOAA/NWS

In the summer, the polar jet stream is usually north of the United States. In the winter, the polar jet moves down, often past the place marked with an "X".

How will the weather at point X change as the polar jet moves from north of it to south of it?
A.
The winds will change direction.
B.
The weather will stay the same.
C.
It will get cooler.
D.
It will get warmer.