Massive heat flux at 10 hPa predicted in GFS, in agreement with most other models, but will it be enough to get a major #SSW? Definitely going to be a significant perturbation either way, but at >10 days out it's hard to say for sure yet. pic.twitter.com/6fEooEU7pr

— Dr. Amy H Butler (@DrAHButler) December 14, 2018