Another piece to the late month cold shot ~15th to 20th or so right now is the evolution of the NAO (Greenland block).

A strong onset of a -NAO historically results in warmth right away.

As things adjust and evolve the lag of a strong -NAO tends to deliver what everyone… pic.twitter.com/iIuAbNCqnf

— BAM Weather (BAMWX) (@bamwxcom) November 30, 2023