There is a growing discrepancy between the GFS & GEFS in the strength of the 10 hPa 60°N [U] after Nov 20th.

Both models have a very similar evolution of the vortex in space, but the GFS maintains a *much* colder core (deeper cyclone) & thus stronger winds. pic.twitter.com/ycJQv7Dgoj

— Dr Simon Lee (@SimonLeeWx) November 13, 2019