Severe Siberian icy blast

IDO , you really do puzzle me , the GFS op is no better , how is you posting a chart for the 5th JAN back to reality ?! The only reality is the today and maybe up til Xmas day at the most , they both won't verify but given the activity in the strat I can confidently say the vortex won't look like that on the 5th jan , not saying cold for us but it won't be organised like that .

Very close to a very good chart the last one you show , greeny high and undercutting lows . Mmmmm , give it till 4pm and it's be all change again !

Erm sorry but just about everything there about the strat warmings is a load of tosh .The warmings we had in November done a fantastic job of halting the strengthening of the vortex , but since then until now we'v had no warmings and no waves . So we'r entering a period of very stong wave activity about to start with fairly significant warmings, more so than anything we had in November . And the results won't be known untill they get well under way . December was dead in the water strat wise mainly because of the Asian low development but we'r on the onset of changes up above and the effects will take a while to be felt . Look how volatile the models are . So really looking behind t144 at the minute is really just for fun .

I'm trying to find judah cohens updated forecast but his site is offline due to technical issues , I'm hoping someone can give me a briefing as to what was said as there's some negativity surrounding it ?

I no Nick , we all knew the models would struggle with a pattern change , Tamara's post illustrated the volatility of the models as they get to grips with the drivers behind the scenes , but I don't think we/me realised how much they would struggle , big swings at relatively early frames . Which is why I really think it's completely pointless in posting endless charts of d16 mean charts buts that's another debate I really can't be arsed to get into again ! After my negative annalysis yesterday I'm feeling slighltly more positive going forward , mainly because there's a fairily significant warming happening high above our heads starting now and continuing for the next 10 days+? Models really haven't got a clue at the minute and signs are now starting to appear in the form of hights to our North east , not quite sure what's happeneds to the neg PDO does seem to have waned somewhat ? But purely looking at analogues of past years , with a strong aluetian low in place that normally correlates with the siberian high , so maybe the excpected winter pattern getting its act together ?

Blooming eck the biggest difference there is the difference in the strength of the vortex, 18z has a much weaker Canadian vortex than the 12 . Should make a slower evolution with better hights holding for longer maybe ? Shows the volatility of the models at the minute .

About cohens forecast , I feel sad saying this but I have to admit I'm a bit disappointed in the way things are turning out , december has been and is different synoptically to what they thought , the main difference been what's happened to our East over Asia really , but it also tells me that in reality yes we can look for signals going forward , but the weather really , has and continues to have different ideas , whilst some excellent posts by experienced ones on hear point toward a pattern change , it's clear that they are only forecasts , and the -PDO that looked to be a major pattern change going forward isn't really having the same implications down stream as one would expect , I no that there's still a lot of uncertainty but if I'm been honest with myself I just don't see an amplified ridge lasting, and more inclined to think it wil be more of a toppling mid atlanitc ridge , the wave 2 forecasts that we'r all looking for comes as a result from a very -PDO and a resultant Greenland high which will pump WAA into polar regions , then a trop led stratospheric response , so if these fail to materialise then that has knock on effects going forward . So with Cohen now forecasting a restrengthening of the vortex , I ask myself can I trust any forecast going forward ? That answer unfortunately is no , however it's easy to see if this pattern upstream fails to materialis then big question marks are there for a cold spell at least for the first half of jan . I'm been honest with how I see things and not saying the writings on the wall at all I'm just airing my thoughts .

I can't back this up but I remember there been talk of an upgrade early December 2012 I believe ? It's not been the same since , afte t144 when wiewing the North Hemi you can litterly watch it go on over drive , it's normally very progressive with the whole pattern , re-organising the vortex as if there a switch been turned on , I vividly remember ones talking about an upgrade but a few people said it hasnt had one but I no what I heard . And it has been a very different model since re the later stages of it .

Not saw too many Synoptics like this , greeny high , Scandi trough and Azores high ! Think the models are having a wobble to be honest doesn't really teleconnect too the background drivers well at all. We saw the models do this in 09/10 and dec 10 , they drop it and then pick it back up much closer but it needs to change back this next 2 days really . Otherwise yet another cold spell took from our noses and we never learn !

Hi Matt , Im now thinking that your first prediction of the SSW of 7th jan may actually be on the money ?! How ironic that would be , I think so much attention has gone into what was happening out east , we may of took our eyes off the developments upstream ? I think the low pressure annomalies over Asia during December really took everyone by surprise , which has had a knock on effect re wave activity , but I think the damage was already done during October and November , which really prevented the vortex in developing to its full . Its ironic that this next development looks like been trop led , mainly from the -PDO really . So really just wondering like I said at start of post , is it realistic to look at a poss SSW during the first 10 days of jan ? But obviously with us looking northwest rather than North East ?

Il be honest , the last few frames on the ecm over the last 2 years maybe? Really from t168 seems to be really progressive in terms modling. Yes the ecm is the best in the world in terms of how it handles blocking situations particualry continental feeda , Scandi blocks ect , but I'm always very dubious of it after t168 , as I am with all of them really , but the GFS is an American model isn't it? So would you expect it to get that area in question right maybe? The same as the ecm as a European model handling continental blocks well? Stands to reason ? I mean when was the last time a t240 verified ? On any of them ? Let's mot worry about details or charts 10/11 days away , the trend been is a greeny block of sorts more North Atlantic based really , how far west/East/North is still up for debate , but the trend is colder around Xmas time with snow becoming a genuine risk , weather it's showers or longer spells of snow , shallow features or what ever , but it's a dam site better than last year and feel the new year is going to bring very interesting synoptic indeed .

but the link has no Boxing Day blizzard , snow in the northwest with a rain event for the rest of England . Far too early to be analysing ppn charts at t200 away , the ecm looks way over the top with them lows like that , probably much further south as Steve m says , but pointless at minute lets all just look for trends .

Yes that's correct , we need those arrows going poleward rather than toward the equator . Quite important really and would be a shame If this goes wrong for us .

Well it's not dubious though is it ? The second chart would give us a good northerly of sorts maybe Northwest . Good ringing into Greenland . Just no low hights into Europe but quite a good chart if you ask me

I think we should all agree to disagree because in my eyes the Azores will not be a player . Low pressure Europe , -AO setting up . Ridge over Alaska but pushing towards west Greenland . Don't see the Azores spoiler .

Again too far out to be taken litterly because it's only indicative of that particular time frame on the GFS so how reliable is it ? But always good to see the jet going South which can promote high pressure to our North !

The mean at t384 to me indicates low pressure well South into Europe, the removal of high pressure to our South and high pressure still over west Greenland , aswel as hinting at a more negative AO . Not that I would ever look at the mean at so far out for any guidance tbh .

Very nice diagram which would be ideal if happened but it's very unlikely to be honest . there's too much energy in the vortex segment over Greenland to allow the ridge to be pulled up like that . Maybe the Azores can ridge more WWN toward to the east coast of America giving more of a northwest flow but at the minute a greeny high is very unlikely at that time frame . Maybe just after Xmas perhaps look to our Northwest but not yet . All the same the vortex is going east and the East Pacific Oscilation does look like going negative with time which will drive cold air South into America and normally produce a ridge to the east of that in reply to the pressure distribution over the above areas stated . I think that's where we need to watch but not just yet . But I do believe a pattern stage will show it's hand in the models before Xmas but won't verify until after Xmas which should at least give interesting model watching leading up to it !

You contradict yourself somewhat to be honest because on one hand you say it's the same as last year but yet on another you recognise the vortex is weaker . You know that the background winter drivers are very different this year to last . And considering last year was the wettest winter on record really makes it even more unlikely. If you mean we're heading for a zonal winter then I should be very wary of charts more than 150 hours away let alone t240 . A pattern change is emerging . -PDO , transportation of the vortex to the other side of the pole , very strong wave activity beginning Xmas week , all these things will force a pattern change , with the AO going negative along with the NAO , so I doubt very much tbh . Not sure whether you read Tamara's post earlier but if not I would really recommend it ?

Haha that's what I use to do.when I was a kid u use to call this long range forecast in the hope it mentioning snow a week away. I got banned from the house phone as a kid cause I ran up massive bill after massive bill. I found weather two before netweather . But since netweather iv never looked back and it's almost changed my life since ! Sounds mad doesn't but that's the truth.I would put myself as a 10 . examples : Stay up all night with window open taking videos and pictures : Lampost watching waiting for the first signs of the rain turning sleety gradually watching the transition to snow and the first signs of slush on car and pavements !: Back in November I actually became obsessed with the Web cams in upstate new york with the buffalo lake effect snowfall . Litterelly obsessed completely in awe reading the forums over there and how they feel as strongly as we do over hear about the snow lol: Snow has the power to change make or break my day so if it changes path at last minute I become a vile man and use to just go out and get hammered with my mates to forget it !!!: And finally the fact Iv been awake since 5:30am reading this and decided the post at this silly hour really says it all doesn't it ?!! : Oh and yes iv moved me and the mrs to the cotswolds 700ft above sea level!! : Definitely a 10 there I'm afraid I don't no how my poor wife copes LOL!!

Ummmm no it doesn't not really . That's surface highs over Greenland . Still nothing in the models this morning to suggest anything in any way . We all look desperately with cold blinkers clouding our judgement . But in reality untill we see evidence on the models there's no chance of change

Wise words , which although hasn't occured yet , it just reminds me of the unpredictability of the weather , whilst the strat warming gives us hope , it's also a reminder to me that even with other factors on our side this year , for example the massive SSI we saw in October , the weather in the main has its own ideas , because at the turn of the month the massive russian high was replaced by a massive Russian low ! Which really holted the progression of the feedback process , infact it was indicative of a low snow advancement index , which really gives question marks on the reliability of it . Of course that's now reverted back to the expected pattern of high pressure over there, Sure a "a cold hearted winter" may well happen , let's all hope so , but a SSW doesn't guarentee a thing in itself , just increases our chances . Time will tell I suppose . I for one hope for a flip in the models ASAP and know how quick models can change , just hope the high doesn't get into South europe cause that can be one disgusting pattern.

Lol I'm guessing he meant of what he feels it could lead to ?! Granted not the best choice of words but if you look at the vortex , for the 18th dec that's one shakey vortex . Certainly not the dizzy strength of last year , I can see the potential of that chart going forward but wrong in both terms , no Scandi high and no greeny high , but with the disorganised vortex and with big Russian hights one can see how it could envelop maybe?? Just premature in his wording !

I don't get why people trying to analyse so much ? A Continental block means a vast variety of options . All we no is the Atlantic is on its way out. And fergie did say signs of a -NAO as we progress through the month . So all in all a very positive update. Given the background signals this year I doubt we need to worry too much about a mid lat block ? With the snow index so strong this year it seems logical to expect the siberian high exerting it's influence further West with time doesn't it? No need to worry and get caught up or reading too much into what was said . But it's a positive step in the right direction definitely .

Ian I have to say , you've just made my day , a otherwise grim typical Monday monday has just been transformed into a very happy day !! We'v been looking for this in the strat thread , really good to see your excellent model is also picking upon this . Possibly a wintry Xmas period coming up ?