Not much coupling! Differences from average atmospheric thickness (“standardized geopotential height anomalies”) in the column of air over the Arctic for the stratosphere and troposphere. For much of the recent period back to early November, the stratosphere and troposphere have been largely uncoupled. The main exception was in mid-to-late December when the low thickness anomalies (indicative of a stronger than average polar vortex) extended from mid-stratosphere to the surface. The latest forecast predicts that this weak interaction will continue for at least the next two weeks. Standardized anomalies are based on departures from the 1991-2020 Climate Forecast System Reanalysis climatologies and have been divided by the standard deviation. Data are from the Global Forecast System observational analysis and forecast.