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polar vortex

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  1. I think -QBO works well with low solar and moderate Nino however if the QBO like this winter is to negative this can have a detrimental effect towards northern blocking. Just my opinion of course. One other point that may or may not be of relevance regarding the winter of 62/63 during the October of 1961 the largest detonated nuclear bomb (the Tzar bomba or king of bombs) was dropped over Novaya Zemlya with a yeild measurement of 50 megatons. This would have surely had a impact on the stratosphere remembering of course that the March of 62 was very cold with extensive northern blocking. Maybe this had repercussions for the following winter as well.
  2. Despite what some say the reason for another poor winter (so far) has been the strength and orientation of the vortex which again has been underestimated. last year the vortex was stretched from Siberia to Hudsons bay area and actually allowed a negative AO anomaly of almost 1 SD compared to +1 this january. I am wondering what with the Jan QBO coming in at -26.70 by far the lowest reading for January since 1979 whether this would have the effect of strengthening the easterly winds around the equator but by being so strong not allowing them to expand further north as seen below from the 30 hpa mean zonal wind. Apart from 1 or 2 very brief easterly transitions you can clearly see the dominance of strong westerly zonal winds.
  3. I think it is quite obvious the vortex is a lot more durable than we give it credit for both higher up and lower down. Also warmings that just circle the surf zone tend to tighten and strengthen the vorticies (which make sense when you think about it). That was the main problem last winter and to a certain extent has been the problem this winter.
  4. One other point to mention although I think most are aware of this and that is that as we move further into February towards March lapse rates increase, so where in December or January -10 uppers would usually translate to surface temps of around 0c to +1c by the time you get to say the third week of February you would probably be looking at temps of around +3c and increasing further as you move into March. These are of course a rough guide to temps on a sunny day and where as in December or January it does not really matter that much but makes a big difference in later on during February and into March. Of course there are exceptions to the rule especially with a deep cold sourced easterly but as I said this is just a rough guide.
  5. You are of course quite correct in what you say. After all it is only 1st of February and it is only midday therefore you might even max out at 6c which you would be hard pressed to call even rather cold even if the wind is a tad nippy. Talk such as not living in Siberia etc is a tad unfair as we all know given the right synoptics from the north, or east etc it can be very much colder than this. The Met have been using terms such as deep cold etc which does not even gell with their definitions of what is rather cold, cold, very cold etc and is typical of the way they over hype these type of events when we are having a generally mild winter. Of course this is much better than anything we saw last winter but it still does not make it a decent cold spell or even close to being one.
  6. This is the strat profile at t 216 70mb from the ECM and you can see a week sausage shaped vortex which would be conducive I think for height rises to the north, north east rather than over the Greenland plateau. If this is a new trend from the 06z then perhaps we will see more amplified heights to the north, north east from t96 onwards.
  7. I think the 06z is much more believable than the chances of pressure rising north towards Greenland as S. Murr has suggested. The reason being that we know that the strat profile shows the vortex moving back towards the Greenland area in the mid term and if this is so then it would leave the door open for higher heights to our north, northeast perhaps. Of course I could be talking a load of cobblers agreed but it would make sense to me. I would take the 06z run with both hands as I am sure most on here would but we have been here before where a cold spell looks lost only for a run from one of the models to resurrect it only to find it was a complete outlier and red herring. Still because of the reasons mentioned above and the stage of winter we are now in I am in the GFS 06z camp and rooting for another 100 or so miles of amplification then we really would be in a deep,deep freeze.
  8. Ah I can see where the precipitation is coming from now. The radar had not refreshed and all it was showing was the precip exiting the east coast. At least I know what peeps are talking about now. Thanks.
  9. Could someone please point me in the direction of where this potential snowfall or precipitation is coming from.
  10. I must admit if I lived in the southeast corner, Kent especially I would be very excited about the prospects for next week. I remember seeing and reading about it during seventies and eighties where it would be dry inland etc but the far south east and kent would have up to 12"of snow. I am not saying that there will be 12" of snow but the potential is definitely there for some moderate to heavy snowfall.
  11. I have mentioned this two or three times already this evening and I.F. has alluded to threat of significant snowfall for the more western areas perhaps. As you say though the track at +t72 is far from resolved. If it did take a more east southeast track along the channel then apart from the risk of widespread heavy snowfall it would also force the high to ridge further north and draw in an even colder stronger easterly. The Euro models have it much further west and south where as to my eyes the GFS has it much further north as it turns and further east/ south east.
  12. Apart from coastal counties that would be dry as a bone inland as the model shows. Plenty of time for that to change though. Sunday morning there are opportunities over eastern england and into east Anglia and the southeast perhaps.
  13. Agreed. We really want to see a strong easterly flow with instability mixed in leading to plenty of snow showers feeding in off the north sea. Alas this is not been shown at the moment. Why we nearly always have this problem with the high to far south sending the coldest and snowiest weather into southern Europe. Still plenty of time for the output to change to our way of thinking perhaps. I think the track of the low moving south at t72 is still far from settled yet and this could have a big bearing on what follows depending on track and depth. Still not buying into the the dominance of the low heights to the north in the mid to long range just yet either.
  14. That is a lovely looking chart I must say. Much better ridging than the GFS and surely a much better chance of a more potent easterly. I noticed on the GFS run the low started to track east much earlier at t72 if this is a new trend then could we be looking at a channel low. Also the low is much deeper on this run which would help sustain better heights to the north.
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