Model output discussion - 16th Nov onwards

[Summer Sun]

A good chance of some more snow for parts of northern Scotland on this run from GFS - highest number the snow row can get to is 23

 

Edited November 21, 2015 by Summer Sun

[Hotspur62]

A few posts saying the outlook is positive if you like cold. May I ask, what are the signs, and are they not the usual signs that appear every year? Looking at the charts myself, I see a broadly west, to north west regime which would produce average to possibly a tad below (in general) conditions.

Are people 'hope casting' or am I missing something?

Thanks

 

Agree. Much as I  would love to see a cold spell develop like most on here I don"t think there is enough cross model agreement to suggest that to happen in next 14 days. Whilst there could be snow on northern hills in England and Scotland in next 7 days I really can"t see a "proper" cold spell for the UK. Equally , it is fair to say I think we have seen the end to truly exceptional mild temps that we have experienced for the first 19 days of November and it is nice to see "seasonal" temps for next week. At least  a trend downwards for temps and lets hope that continues as we progress into winter. After all we are still in Autumn and todays snowfall across parts of the UK can be seen as a bonus.!! 

[Newberryone]

A much stronger SH on 12z ECM compared to this morning's run Trends

  

All looks very good for cold

I'm obviously missing a key ingredient not to mention something very significant here in how I'm interpreting the latest charts in relation to cold weather prospects for all I can see is a massive high pressure cell occasionally ridging slightly north from the southwest. In essence it just looks like the dreaded Azores high that's fully intent on inviting an unwanted guest such as Uncle Barty to hamper our chances of receiving anything that would be considered noteworthy in terms of cold weather.

[nick sussex]

  I'm obviously missing a key ingredient not to mention something very significant here in how I'm interpreting the latest charts in relation to cold weather prospects for all I can see is a massive high pressure cell occasionally ridging slightly north from the southwest. In essence it just looks like the dreaded Azores high that's fully intent on inviting an unwanted guest such as Uncle Barty to hamper our chances of receiving anything that would be considered noteworthy in terms of cold weather.

Theres no chance of the unspeakable horror that we dare not mention! With high pressure to the east/ne low pressure is forced se into Europe. The Azores high generally remains displaced to the west/sw. As long as you maintain high pressure sufficiently north then some energy heads se and doesn't all run over the top. The most evident thing from tonights GFS/ECM is although the PV blows up this doesn't last long as this becomes split.

[Cheshire Freeze]

I must admit I'm really really struggling to understand some of the general negativity in this thread? Here we are on the 21st November with some already having seen snowfall, we have modelling which is pretty much unanimously supportive of Siberian heights and a gradual further weakening of the tropospheric vortex and on top of this all the suggestions of a late December SSW.

 

IMO the outlook is the third best early winter outlook of recent years- behind '09 and '10 and even then if you took away the preconceptions of a 'nino winter' I think we'd sneak in front of '09 based purely on the output we're seeing at present.

Edited November 21, 2015 by CreweCold

[knocker]

The ecm anomaly at day ten is more or less on the same page as the GEFS. At T360 it has HP over North America, a weak trough Greenland/Iceland and HP over Russia. But it also ridges the Azores HP up from the south west so the whole of the UK comes under the influence of Tm air from the WSW resulting in more settled and warmer conditions towards the end of the period.

Edited November 21, 2015 by knocker

[dragan]

I must admit I'm really really struggling to understand some of the general negativity in this thread? Here we are on the 21st November with some already having seen snowfall, we have modelling which is pretty much unanimously supportive of Siberian heights and a gradual further weakening of the tropospheric vortex and on top of this all the suggestions of a late December SSW.

 

IMO the outlook is the third best early winter outlook of recent years- behind '09 and '10 and even then if you took away the preconceptions of a 'nino winter' I think we'd sneak in front of '09 based purely on the output we're seeing at present.

From a very novice point of view, if you mean the disappointment from a coldies perspective then its obvious...basically all the way out in FI there is pm air at best, as Knocks said, even tm air with a gradual warm up is a real  possibility.

So that is why i asked the question 'am i missing something' as some mention the conditions look good for cold. Im totally objective (i enjoy all weather), but the thing is, in Britain even if all the signs point to a possible cold evolution, 9 times out of 10 (probably more) they never materialise.

[Cheshire Freeze]

From a very novice point of view, if you mean the disappointment from a coldies perspective then its obvious...basically all the way out in FI there is pm air at best, as Knocks said, even tm air with a gradual warm up is a real  possibility.

So that is why i asked the question 'am i missing something' as some mention the conditions look good for cold. Im totally objective (i enjoy all weather), but the thing is, in Britain even if all the signs point to a possible cold evolution, 9 times out of 10 (probably more) they never materialise.

 

Yes but that's the issue when you consign yourself to focussing on our tiny little part of the globe. Look at the output in NH perspective and have a look at just what is going on at the N latitudes...if you do you will soon see that not all is well with the vortex. After that, go and have a look at the NH perspective for a horror +AO winter (there have been plenty) and you'll soon see the difference.

 

True, we have seen cold spells that have failed to materialise but often in these instances the 'foundations' have not been there and when I say foundations I mean the state of the general NH pattern. That is why I'm intrigued by the progged situation- the foundations are being laid very very nicely from what we've seen so far. That is to say, should any cold spell emerge in the modelling, I will be more inclined to put more faith in it due to the groundwork that is being put in from here on in.

Edited November 21, 2015 by CreweCold

[Timmytour]

I must admit I'm really really struggling to understand some of the general negativity in this thread? Here we are on the 21st November with some already having seen snowfall, we have modelling which is pretty much unanimously supportive of Siberian heights and a gradual further weakening of the tropospheric vortex and on top of this all the suggestions of a late December SSW.

 

IMO the outlook is the third best early winter outlook of recent years- behind '09 and '10 and even then if you took away the preconceptions of a 'nino winter' I think we'd sneak in front of '09 based purely on the output we're seeing at present.

Not meaning to be negative at all, and indeed I can see plenty of potential in the models But I'm not so sure an SSW would improve upon that potential. Isn't it the case that just as an SSW can turn an ordinary winter into something wonderful, it can also put a spanner in the works of what was a promising winter?

[Cheshire Freeze]

Not meaning to be negative at all, and indeed I can see plenty of potential in the models But I'm not so sure an SSW would improve upon that potential. Isn't it the case that just as an SSW can turn an ordinary winter into something wonderful, it can also put a spanner in the works of what was a promising winter?

 

It really depends how it manifests I think? We're likely to see a nagging issue with an area of low heights around Greenland with any reformation of the vortex (as can be seen during the next week). If we get lucky then any SSW could potentially put an end to that scenario. Just how long is a piece of string?? 

[dragan]

Thanks crew, just wanted a bit clarity. Wasn't being arsy, genuinely just wanted a bit of 'why' the outlook looks good. Your expectations are always spot on

[Sweatyman]

I must admit I'm really really struggling to understand some of the general negativity in this thread? Here we are on the 21st November with some already having seen snowfall, we have modelling which is pretty much unanimously supportive of Siberian heights and a gradual further weakening of the tropospheric vortex and on top of this all the suggestions of a late December SSW.

 

IMO the outlook is the third best early winter outlook of recent years- behind '09 and '10 and even then if you took away the preconceptions of a 'nino winter' I think we'd sneak in front of '09 based purely on the output we're seeing at present.

until you read a post by knocker which contradicts

[bluearmy]

Been saying it for a while now - the blocking to our ne is going to be the story for December. Just depends if it can make it this far west. Signs that the vortex might be split/stretched with the deeper chunk on the Pacific side could just be enough? We wouldn't expect the Siberian high to make a difference this far west in December but I'm Impressed with the gefsp at day 10 when compared to ECM (re similarity) so why not take the extended data with a bit more interest than just entertainment value?

Have a look through the members in two weeks time.

[Liam J]

I assume some are hoping the Siberian high may extend westwards enough to possibly bring the UK an easterly? I might be wrong but it would likely have it's work cut out if the vortex/deep trough sets up around the Greenland locale as per some of the models are showing, keeping the UK under an Atlantic influence while the cold air gets tantalisingly close but not close enough and prove majorly frustrating.... I can understand the positivity but view with caution.  

[Cheshire Freeze]

Thanks crew, just wanted a bit clarity. Wasn't being arsy, genuinely just wanted a bit of 'why' the outlook looks good. Your expectations are always spot on

 

Nahhh as with anyone, my expectations are never always spot on but I'm glad I could be of help to you...remember, look at the NH pattern!

[Rocheydub]

I assume some are hoping the Siberian high may extend westwards enough to possibly bring the UK an easterly? I might be wrong but it would likely have it's work cut out if the vortex/deep trough sets up around the Greenland locale as per some of the models are showing, keeping the UK under an Atlantic influence while the cold air gets tantalisingly close but not close enough and prove majorly frustrating.... I can understand the positivity but view with caution.  

Indeed. Past recent history (I think 2012) will show how really difficult it really is to retrogress a Siberian HP cell far enough west to really effect our weather on these islands. And if it does, it will only effect most probably the east coast and it's neighboring regions on England and Scotland. All we can hope is that this Siberian HP, can offer some warm air advection into an unstable vortex, and hope the dice falls our way!

 

That said, I wouldn't lose all hope folks, I mean, winter is still 10 days away yet!

[Cheshire Freeze]

That said, I wouldn't lose all hope folks, I mean, winter is still 10 days away yet!

 

I wouldn't lose any hope at all......

 

The Siberian high was never going to directly affect us (although there is a very slight chance it could further along). More pertinent to us in the UK is the effects that the high has on the NH pattern and more specifically the effects that it has on the vortex. Get a good Siberian high in place and some associated WAA and you've pretty much won half the battle of getting a -AO. Once you've got a -AO you've pretty much won half the battle towards getting a -NAO. See where I'm going here.....??

[PolarWarsaw]

The ecm anomaly at day ten is more or less on the same page as the GEFS. At T360 it has HP over North America, a weak trough Greenland/Iceland and HP over Russia. But it also ridges the Azores HP up from the south west so the whole of the UK comes under the influence of Tm air from the WSW resulting in more settled and warmer conditions towards the end of the period.

 

With respect - these are the same Anomalies that didn't pick up the bitter period this weekend. If we were to go by the anomaly's you have posted for about the last 6 weeks, we would be deep into a zonal train with no end in site..when in reality there has been plenty to keep everyone interested. The reliance on these charts and all that they entail is predominantly futile and misleading, especially when truly into fantasy land like T360. If a coldy finds a chart at T360 they get buried (ironically) under all the ribs aimed at them. 

Edited November 21, 2015 by PolarWarsaw

[Snowmad79]

I have to say guys, with an El Nino event underway we could be staring at far worse outlooks. I think the models are looking okay to be honest. No sign of any Euro high pressure, HP modelled to build over the artic (negative AO ?) and for our region a negatively tilted jet with troughing into Europe. Low pressure over the med is a generally a good thing at this time of year. I really don't see any mild mush, more Cold Zonal with wintry showers for the usual suspects as cold NWerlies hit.

 

[chrisbell-nottheweatherman]

With respect - these are the same Anomalies that didn't pick up the bitter period this weekend. The reliance on them and all that they entail is predominantly futile and mis-leading, especially when truly into fantasy land like T360. If a coldy finds a chart at T360 they get buried (ironically) under all the ribs aimed at them. 

 

I don't know whether this affects the discussion at all, but Weatherweb.net have released a video in which they examine the CFS anomalies through until mid-December, and, after brief meriodional flow this coming week, they're indicating a mean pattern which is pretty much flat zonal. 

 

Video link:

https://www.youtube.com/watch?v=-uIINurSVb0

Edited November 21, 2015 by chrisbell-nottheforecaster

[PolarWarsaw]

I don't know whether this affects the discussion at all, but Weatherweb.net have released a video in which they examine the CFS anomalies through until mid-December, and, after brief meriodional flow this coming week, they're indicating a mean pattern which is pretty much flat zonal. 

 

I'm not at all saying that they aren't of some use, but they are just as flippant as deep FI is in a normal model run and they shouldn't be given anymore credibility than T300 is on this mornings 0z ECM. Sure they do look at things as more of a 'mean' point of view - but honestly, they fail to pick up on a short term events and little differing details. 

[Rocheydub]

I wouldn't lose any hope at all......

 

The Siberian high was never going to directly affect us (although there is a very slight chance it could further along). More pertinent to us in the UK is the effects that the high has on the NH pattern and more specifically the effects that it has on the vortex. Get a good Siberian high in place and some associated WAA and you've pretty much won half the battle of getting a -AO. Once you've got a -AO you've pretty much won half the battle towards getting a -NAO. See where I'm going here.....??

Of course I do. This is mother nature, anything is possible, and often unpredicted!!! I would be a lot less optimistic than the vast majority that posted before me stating the Sib HP is good for us. Yes, it could be worse, a lot worse, but I would hardly be so positive with this current set up, if it's proper cold and snow that you want! (ME!)

[BLAST FROM THE PAST]

I agree the anomaly charts didn't see this period coming and we should be N/S split and flat zonal...they were out.  They will be out too over next 2 weeks.  Some excellent posts going on here and agree with many....

 

If a big freeze kicks in I'll be surprised, but I'll be just as surprised if we load into a mild dross outlook.   Plenty to be seasonal about....and its only Nov 22nd.   18z started on same track as earlier runs...let's see how it pans out

 

BFTP

[BLAST FROM THE PAST]

T234 to t240, very interesting.  Block looks like it has strengthened and early hint of trough disruption.  Expect a SE dive of the trough, different to 12z for sure locally and could lead to HP moving/building across us mainly in the south....

 

 

Edit - a small lobe dislodged SE, but a Knocker anomaly run as we go into Dec...and why we mustn't jump the gun.  Too early for me if one reads my Dec outlook but I see the idea.   I'll blend the 12z and 18z for me

 

BFTP

Edited November 21, 2015 by BLAST FROM THE PAST

[bobbydog]

I wouldn't lose any hope at all......

The Siberian high was never going to directly affect us (although there is a very slight chance it could further along). More pertinent to us in the UK is the effects that the high has on the NH pattern and more specifically the effects that it has on the vortex. Get a good Siberian high in place and some associated WAA and you've pretty much won half the battle of getting a -AO. Once you've got a -AO you've pretty much won half the battle towards getting a -NAO. See where I'm going here.....??

the Force is strong with this one...

Winter 2015 -a new hope....

Edited November 21, 2015 by bobbydog