Nearly all ECMWF Monthly model ensemble members reversal 10mb zonal winds during early January. This illustrates a significant sudden stratospheric warming event will be at hand. Still waiting to see if the Stratospheric Polar Vortex splits or not, but there's a good chance here. pic.twitter.com/XjzsSbgIiS

— Mike Ventrice (@MJVentrice) December 26, 2020