December worked out okay, except for the fact that it was PNA and not RNA....this caused the se and se to flip anomalies from what was forecast.
Most of the forecast for January still appears valid...trends for less "blocking" and perhaps more PNA intervals again as the month progresses. The lower heights towards AK have already began materializing, but the N ATL ridding has not yet began to abate. I would look for signs of that in longer range guidance as the New Year approaches.
January 2021 Outlook
January Forecast H5 Composite:
The active winter pattern may carry over into the first week or so of January, or it may not. This is nebulous, but what is clear is that any residual positive height anomalies should vacate the higher latitudes, as lower heights retrograde towards Alaska. The structure and character of la nina begins to assume a more modoki state, as it peaks and begins to decay. The Aleutian ridge relocates to the southeast, away from Alaska. Heights near the pole should not be exceeding low, nor the temperature departures extremely high like January 20202. But nevertheless, the pattern grows relatively hostile to sustained wintery interludes in the east.
January Forecast Temperature Composite:
Temperatures should be near normal to 1 degree above across northern New England, 1-3 degrees above normal in central and southern New England, and 2-3 degrees above in the mid atlantic. Any storm activity will entail large precipitation type issues near the coast, with the most snow reserved for northern New England. The RNA pattern should only strengthen, as overall storm activity wanes.
January Forecast Precipitation Composite:
A lull in winter for the northeast, especially below the latitude of northern New England and east of New York state, should develop during the month, as storms becomes less frequent and the predominate track shifts inland. Some seasonal cold bouts should be sufficient for some mountain snow, and perhaps some "front end" wintery precipitation further to the south.