Looking at angular momentum plots a case may be made which disagrees with the longer term model guidance for heights to fall across the North Atlantic. That would call into question the speed of any potential attempted moderation of cold surface temperatures shortly to be embedded across NW Europe.
Tendency in relative angular momentum is well, well above average and a clear indicator that El Nino has successfully drawn the cooperation of the coupled ocean-atmosphere loop.
Anomalous westerly zonal wind anomalies are showing up in both hemispheres across the tropics and sub-tropics fully cranking up the sub-tropical jet streams.
The Global Wind Oscillation is in phase 5 / 6 transition at high amplitude reflecting the surge in angular momentum:
Frictional torques are still positive whilst mountain torques are neutral. In all probability, there will be another increase in mountain torque over the next 5-7 days which should drive the GWO back into phase 5, further adding momentum. This increases the chances of us remaining in phase 5-6 type orbit for a little while yet. The basic gist of this is that perhaps modelling is being progressive whilst the complex fluxing and eddy transport will be regressive with the pattern. I think a case could be made over the last 10 days of the models rushing evolutions. I've been looking at a couple of historical analogues and 1978 is cropping up on a routine basis. Feb 1978 saw the GWO meandering around phases 5-6-7 for the majority of the month - the net result was pressure being high over southern Greenland, the Hudsons and the North Atlantic.
All of this means that pressure may well be higher to our west and north west for a longer period than currently modelled and the trough to our east also being stronger than modelled. The effects of a reversal in polar westerlies looks like occuring around day 8 in the lower troposphere which would tend to draw the ridge out to our west further north. So whereas some longer range models suggest an attack from the SW winning at least for southern Britain, I'm not so covinced it will that quick as the trough to our east may well be stiffer than anticipated.
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