The trend plot on today's 12z ECMWF Ensemble reveals a lot about how this big -NAO cropped up all of a sudden in the models.

The upper trough that passes south of Greenland digs a little more over the next few days...

Like a domino effect, this minute tweak in the forecast… pic.twitter.com/L2Hd90Iwbb

— Eric Webb (@webberweather) November 22, 2023