Thanks. I'm getting the impression that even my assumptions regarding ENSO and the Stratospheric vortex are not as cut-and-dried as I thought. I based this assumption of the following blog article from our own Nick Finnis and from our winter forecast, in particular, the section entitled "ENSO Conclusions":
http://www.netweather.tv/index.cgi?action=news;storyid=6991;sess=
http://www.netweather.tv/index.cgi?action=winter-forecast-2015;sess=
I presume that factors such as Eurasian snow cover and the QBO are much more predictive in terms of vortex strength than ENSO? As regards the Euro high anomaly, it's interesting to note that data confirms my impression that autumn has been dominated by the Euro high. Its influence can be seen even by an ignoramus like me in the outputs posted in the model discussion thread, in that it's combining with the Greenland tropospheric vortex lobe to generate a south-westerly feed over Western Europe including the UK. I never asserted with any degree of confidence that ENSO could have been influencing the anomalous heights over the continent, but I just wondered whether it could be a factor. By the sounds of it, the concurrently-observed lingering presence of the Euro high and the strong El nino may be coincidental?