Model Output Discussion: 12Z (20/11/12) And On...

[Cheshire Freeze]

I almost refrained from making that post for fear of seeming like a misery!

There are ways to get a cold funnel of air into the UK on the southern flank of high pressure and get to retrogression with snowmen intact!

I really don't see how that ECM could get to a Greenland block unless that is we have a Hollywood scriptwriter in here!

Even if the upstream pattern reamplifies there will need to be a milder interlude and alot of sad netweather members seeing the last vestiges of their newly built snowmen turning into a puddle on the lawn.

We need to keep high pressure further north to the west of the UK on the ECM its fast sinking.

Anyway I doubt this ECM run will verify, overall the operational outputs are likely to have a lot of difficulties after 168hrs.

Yes I would say 'thanks but no thanks' to this ECM run. The window for snowfall would be relatively short....perhaps 3 days; certainly not epic by any standards. As you say, some would see snow then be moaning a couple of days later when the snow has melted and we're staring down the barrel of westerlies!

As you have pointed out, we need to keep that high to the north further west.

[ITSY]

people should stop reading too much into 240+ synoptics...every model is right now on board with a potentially potent cold spell/snap. Let us get into it first and THEN we will know how long it will last...

[Ian Brown]

NO SINKER

MY First time of saying this for 2010

HEAVY SNOW OVER ENGLAND & E SCOTLAND.

http://www.meteociel...M1-240.GIF?21-0

S

MORE MORE MORE we need a 264 & 288 Chart

Steve, do you really think that flow would be extending much beyond T240 ? I think the High would end up on top of us by day 11/12 if the run were to verify.

[weather eater]

JMA if anything looks more like the GFS than the ECM, there really is a long way to go before we see just how the evolution is going to go, post 144hrs

[beng]

Great charts, but I reckon the ECM probably has too much energy going North over the top of the atlantic ridge after 168 - we can expect more disruption south of Greenland should the 168 verify - which will result in different 192-240 output (still cold though - possibly an upgrade in fact) - and probably take us more towards the chart GP posted earlier.

On top of that, if/when the cold uppers hit the North sea, then we're going to see shortwaves form - so it could take a little longer for the cold to reach the far South as a result of that. Something similar happened in 2010.

[ANYWEATHER]

After the serious flooding issues in the next few days ,Ecm has a great winter chart aptly for the first day of the Winter!

[beng]

http://www.wetterzentrale.de/pics/Rjma1921.html

JMA looks 'potentially' very Jan 1987 - just need some energy from the atlantic low to head SE and bang.

[nick sussex]

Yes I would say 'thanks but no thanks' to this ECM run. The window for snowfall would be relatively short....perhaps 3 days; certainly not epic by any standards. As you say, some would see snow then be moaning a couple of days later when the snow has melted and we're staring down the barrel of westerlies!

As you have pointed out, we need to keep that high to the north further west.

Yes this is the way to go for a longer cold spell, the ECM looks wonderful for a time but we can still get something similar without the concerns about the jet rolling over the top afterwards.

I'm not trying to spoil anyones fun in here but just pointing out that theres more than one way to get the sledge in action.

Edited November 21, 2012 by nick sussex

[Downburst]

Calm down folks. Cool it. Many runs each day so if you are convinced this one is not 100% wait to see the next before getting all upset. My word. Anyway the 120 to 144 jump is amazing in my opinion. Fantastic Run this. Guys remember a lot of folks here will spend a lot of time moaning during any actual snow, so relax on reacting to any bait.

[Geordiesnow]

Yes I would say 'thanks but no thanks' to this ECM run. The window for snowfall would be relatively short....perhaps 3 days; certainly not epic by any standards. As you say, some would see snow then be moaning a couple of days later when the snow has melted and we're staring down the barrel of westerlies!

As you have pointed out, we need to keep that high to the north further west.

But its only one run CC with any sign of sinkage on the ECM run occuring at 240 hours, I honestly don't understand how people can be negative regarding the ECM run at all in all honesty. That said, the charts the ECM are showing will be subject to change and it won't exactly like that in 240 hours time - it never does.

The main players we need to focus are much earlier on in the run, the models are now pretty firm on a nice amplified Atlantic ridge. This Atlantic ridge may end up linking with a developing Arctic high, this is not certain to occur but if it does successfully then it can prolong any blocking outlook and the chances of cold weather should increase.

Hopefully, no shortwaves over Greenland will hinder this development but as per ever, the models will keep switching the detail aspect of the outputs but hopefully we maintain the trends of blocking. So we are bound too see some runs showing cold weather and other runs something perhaps less appealing to cold lovers.

[Snowmad79]

people should stop reading too much into 240+ synoptics...every model is right now on board with a potentially potent cold spell/snap. Let us get into it first and THEN we will know how long it will last...

Haha, the models actually dont show potent cold until 240hr either. So it works both ways

[chris55]

http://www.meteociel...92-21.GIF?21-12

JMA pretty good- that stranded low over SW greenland will push a shortwave south...

Cant wait for the ECM ensembles.

S

I'm liking that idea!!

[chionomaniac]

Watching synoptics like this is always fun - even moreso if they did actually come off.

Anyway here to continue the fun is my projections for the T+264 chart.

I do think that some people would be miserable with a lottery win as well!

Edited November 21, 2012 by chionomaniac

[Great Plum]

Regardless of its FI status and whether or not it would sink, that ECM run is a modelgasm for coldies!

http://www.wetterzentrale.de/pics/Recm2401.gif

[Mapantz]

Hardly a mention of the synoptics over the next few days and some folks are discussing a breakdown of the blocking/cold?! LOL

I do apologise if it's off-topic but for the life of me, there's some bizarre posts here at times!

[Dexter29]

As an amateur I really do not understand how members can turn great charts into negativity. It's ONE run - this talk of +240 - I mean really, it's FI.. So many charts per day and so many opportunities for major changes good or bad.

Let the cold get here first and stop being such moody buggers.

This is the closet to 2010 we've had since, so bloody enjoy it

[chris55]

Yes I would say 'thanks but no thanks' to this ECM run. The window for snowfall would be relatively short....perhaps 3 days; certainly not epic by any standards. As you say, some would see snow then be moaning a couple of days later when the snow has melted and we're staring down the barrel of westerlies!

As you have pointed out, we need to keep that high to the north further west.

Perhaps you'd prefer this kind of setup?

http://www.wetterzen...00120111128.gif

The projected synoptics are rare, especially at this time of year, my advise would be to enjoy them while you can and hope they verify in one form or another if they do the forecasts will be full of wintry conditions

Edited November 21, 2012 by chris55

[Cheshire Freeze]

Hardly a mention of the synoptics over the next few days and some folks are discussing a breakdown of the blocking/cold?! LOL

I do apologise if it's off-topic but for the life of me, there's some bizarre posts here at times!

If a model suggests a breakdown within its run it's fair game to be discussed. The ECM hadn't even got the cold into its model time frame yet cold was being discussed as shown on the GFS at 300hrs+.

Also, as I've noted numerous times before, looking at potential breakdowns can be important as cold episodes can be eroded from 'both ends' which sometimes leaves a brief cold spell when initially it was looking much more substancial. It's all part of active model discussion (which is what this forum is for); it's not as if I'm actively looking or hoping for a breakdown of cold synoptics, more discussing where it could potentially all go wrong based on projected synoptics.

Sometimes a level head is needed rather than allowing yourself to get caught in the moment of excitement. We all know what happens in the model thread when synoptics end up going pear shaped......bickering, sniping, depressive chat, winter's over posts etc etc ironically by the same members who got carried away by cold charts in the first place!

Edited November 21, 2012 by CreweCold

[Methuselah]

Let's not panic, just yet??

So the GFS and ECM suggest a rapid reversion to something more zonal during the latter stages of FI. And, I think that this is what Ian Ferguson was suggesting yesterday, albeit a wee bit later?

And earlier on, I suggested that we could ignore the 'redrossification' progged by the GFS 12Z, for now. By which, of course, I really meant - hold-off until tomorrow; as predicting the demise of cold spells has always been fraught with danger: 1963, 1968, 1970, 1979, for example, all had instances where 3-day cold snaps lasted for a week or more...

It happens??

[Paul]

Hardly a mention of the synoptics over the next few days and some folks are discussing a breakdown of the blocking/cold?! LOL

I do apologise if it's off-topic but for the life of me, there's some bizarre posts here at times!

Plenty about the rain, flooding and winds this week here

[Snowmad79]

As an amateur I really do not understand how members can turn great charts into negativity. It's ONE run - this talk of +240 - I mean really, it's FI.. So many charts per day and so many opportunities for major changes good or bad.

Let the cold get here first and stop being such moody buggers.

This is the closet to 2010 we've had since, so bloody enjoy it

Im sorry but I'm as desperate for the next 3month severe cold winter as the next snow lover but you have to be sensible and advise caution to anything shown after 96hr never mind 240hr. Lets be honest, as it stands their is nothing notably cold shown until around 240hr so discussing the risks of breakdown or things going pear shaped is just as valid converse as discussing possible cold at that range. So potent cold at 240hr is nailed but it going pear shaped isn't ?

[Dexter29]

Im sorry but I'm as desperate for the next 3month severe cold winter as the next snow lover but you have to be sensible and advise caution to anything shown after 96hr never mind 240hr. Lets be honest, as it stands their is nothing notably cold shown until around 240hr so discussing the risks of breakdown or things going pear shaped is just as valid converse as discussing possible cold at that range. So potent cold at 240hr is nailed but it going pear shaped isn't ?

I never said anything was nailed.

My point is we rarely see such good charts, yes it may not be Siberian air. But it's cold enough to produce snow during the later part of next week.

As always we will always have members picking out a negative outcome before its even begun

[london-snow]

Let's not panic, just yet??

So the GFS and ECM suggest a rapid reversion to something more zonal during the latter stages of FI. And, I think that this is what Ian Ferguson was suggesting yesterday, albeit a wee bit later?

Just take 2010 as a example breakdown put further and further back once the pattern became established - A little tiresome with some recent posts talking of breakdowns ect in far reaches of fi where the pattern before is not nailed on.

Looking into the reliable time frame the pattern change to more colder conditions is pretty much nailed on now and looks to be a more of a progress as we go along type of pattern change.

In terms of posters stating about possible breakdowns in fi then we could also equally say that blocking in fi say day 7-10 range could be underestimated as previous situations have proved.

Just enjoy

[TAFKAP]

Cannot believe some people are whinging that the ECM isn't good enough? Are you kidding me?! It's the best and possibly coldest run of the year!

Why you're worrying about a chart at T240 that the high would sink further on is ridiculous, just enjoy the chart for what it is, nothing short of amazing!

You're right, it is ridiculous. Some people seem to think we live in Siberia or the Arctic. A lot of useless comments by people who know nowt.

[Ice BIast]

The BOM 12Z is loaded with blocking, and it retrogresses the high towards Greenland in the latter part of the run.