Use the video How a warmer Arctic could intensify extreme weather by Vox to find the answers. It isn't really clear to me and I don't trust myself to come up with it
What part of the earth is warming the strongest?
What wind current has been changed by the extra heat in the arctic?
What is happening to this wind current and how is its shape changing?
What happened on the west coast and east coast of the US as described in the video?