Model Output Discussion 29th December - Into mid-Winter.

[Ali1977]

Extended de bilts

Strongest cluster is actually lower than the mean

Edited December 29, 2016 by Ali1977

[blizzard81]

Very difficult for most of us to decipher ext ens as we don't have access to clusters, anomalies etc. Bluearmy's post though does sum up what I feared about the high sitting it's backside on the UK. At least it will feel like winter though.

[winterof79]

 

As Ali posted

[chionomaniac]

6 minutes ago, bluearmy said:

The eps are overall consistent. Subtle differences re the pattern being a tad further east on heights but a  smaller tad further west on anomolies 

in th extended period, we develop the low anomoly train to our south but instead of the upper ridging being generally northern uk and beyond, it is more over the uk so the likelihood that any high will be centred more over the uk than to our north. 

as I said, subtle and generally on the same page but more likely to see any frigid cold sent to our se from this run. 

I would say that the greatest blocking anomaly is just north of Scotland - but that it could be centred anywhere from western Scandi to Iceland to Shetland. Would leave an Easterly chance for the southern half of the country but more settled further north. Presently the really cold anomaly 850 wise is further east. Good to sea the block underpinned by low anomalies to our south

[bluearmy]

5 minutes ago, johncam said:

So guys what are we saying back to square one with high over us?

tough one but not the same as now with euro heights much lower. Likely to see an easterly flow of sorts but whether that's beneath the influence of a high or a proper cold feed from the continent or battle ground as the Atlantic approaches, who knows. what I will say is that the extended ens are steadfast in removing fhe euro high anoms but close inspection of the eps days 8 to 6 over the past two days reveal that the Euro heights are now predicted stronger than they were 48 hours ago! 

ec46 due out in an hour 

[SMU]

21 minutes ago, Seasonality said:

Hi Steve. Please could you elaborate. Maybe with a chart or graph. Because I don't understand how @feb1991blizzard sees a "downgrade" (hate that term), yet you and others see it being good for cold. I  ask because you're better at explaining such set ups than I am.

Yes the debilt ones- note that the OP has only 5 members supporting the same T2M - with significant clustering below - suggesting a slightly higher amplitude wave -

Day 11-15 show whats expected - mean drops to 1-2c  with sub zero clustering

 

For the SE contingent ECM has the frontal zone clearing midnight Sun

 

S

 

 

 

[Seasonality]

Hi all. Just a bit of real time reporting of cold set ups. We've had a little stint of decent uppers and the usual t2m temps around freezing in Warsaw yet little forecast in the way of snow.  Currently have light snow and a little dusting already thanks to sub zero ground temps. Surprises do happen! Keep the faith.

[abruzzi spur]

14 minutes ago, Glacier Point said:

Another eps going for a progressive undercut and block development to the north in the extended range, sustained cold from day 8. Very cold European outlook. Pandora's box about to be opened..

just need to nail the drag back of the core of the pv across the sw USA.

GP, to avoid confusing those members with some classical knowledge, can you please clarify the Pandora's Box thing.  The box actually contained all the evils of the world. Pandora opened it, all the evils got out and all that was left in the box once she closed it was hope.  Given this thread's tendency to hyperbole, I'm not sure it's the best analogy!

[feb1991blizzard]

1 minute ago, bluearmy said:

tough one but not the same as now with euro heights much lower. Likely to see an easterly flow of sorts but whether that's beneath the influence of a high or a proper cold feed from the continent or battle ground as the Atlantic approaches, who knows. what I will say is that the extended ens are steadfast in removing fhe euro high anoms but close inspection of the eps days 8 to 6 over the past two days reveal that the Euro heights are now predicted stronger than they were 48 hours ago! 

ec46 due out in an hour 

Yes, that's like the op, that's because the high isn't sharp enough and too much further East, so low heights further away from a favourable position.

[Methuselah]

2 minutes ago, chionomaniac said:

I would say that the greatest blocking anomaly is just north of Scotland - but that it could be centred anywhere from western Scandi to Iceland to Shetland. Would leave an Easterly chance for the southern half of the country but more settled further north. Presently the really cold anomaly 850 wise is further east. Good to sea the block underpinned by low anomalies to our south

Whilst I'd love to see a protracted easterly, chio, I'd most certainly not welcome anything like today's 06Z: Snow by the bucket-load? Yes. Freezing-fog? Yes. A week between -10 and -20C - snow or not? Not on your life!

I think we can all be thankful that that particular run will never verify!

[Ali1977]

7 minutes ago, Steve Murr said:

Yes the debilt ones- note that the OP has only 5 members supporting the same T2M - with significant clustering below - suggesting a slightly higher amplitude wave -

Day 11-15 show whats expected - mean drops to 1-2c  with sub zero clustering

 

For the SE contingent ECM has the frontal zone clearing midnight Sun

 

S

 

 

 

Ref the front clearing the south, the -5c 850 around the M4 corridor in a Northerly would surely indicate a good chance of back edge snow - minimal but still a chance

Edited December 29, 2016 by Ali1977

[bluearmy]

8 minutes ago, blizzard81 said:

Very difficult for most of us to decipher ext ens as we don't have access to clusters, anomalies etc. Bluearmy's post though does sum up what I feared about the high sitting it's backside on the UK. At least it will feel like winter though.

15 days is a long way away and making a call on where a high might sit itself is a bit pointless. euro troughing has always been tough for the models to resolve and just how low heights may go to our south is going to prove pretty difficult to resolve. It could well end up quite a spread block across nw Europe but then again, it could be a screaming beasterly. mogreps and glosea will dictate exeters prose on the 15 and  30 day tomorrow. I expect they will play safe with the high pressure and colder than average outlook. Don't blame them!

[SMU]

14 minutes ago, Ali1977 said:

Ref the front clearing the south, the -5c 850 around the M4 corridor in a Northerly would surely indicate a good chance of back edge snow - minimal but still a chance

Yes certainly - I would suggest the downs or the eastern end of cotswolds - Dunstable & the usual suspects poss dusting - wet snow for the rest unless we do get a ripple running along the trailing front - im 50/50 for here @ Greenhithe for seeing snow falling sunday as the thames usually provides around 0.5c-1c of upward modification into the lowest levels of the atmosphere impeding those closest ...

SE essex up to Cambs & Herts & across to oxford would be the sweet spots ...

[Glacier Point]

4 minutes ago, abruzzi spur said:

GP, to avoid confusing those members with some classical knowledge, can you please clarify the Pandora's Box thing.  The box actually contained all the evils of the world. Pandora opened it, all the evils got out and all that was left in the box once she closed it was hope.  Given this thread's tendency to hyperbole, I'm not sure it's the best analogy!

Point taken, although; a sustained period of well belows with a mean vector from the north-east alternating with north; just enough residual pv centred west and south-west of Greenland to feed the block; and, during our coldest period of the year, would be viewed by many of the population outside of this forum as falling within the all evils.

[Guest]

one thing i will say is that i find it fascinating how people view the model out put... one person says it a horror show next poster says its an awesome run. it has been a long time since we have seen such eye candy, for many its the first time since 2013.. we didnt have such a bad spell in Jan 2015 up here with some cracking snowfall. anyways not too long before the pub run comes out. will go all out drunk or will it sober the minds of us coldies? either way its been an entertaining day of model out put for sure...

Edited December 29, 2016 by Guest

[Dennis]

Today GFS12 Para

Edited December 29, 2016 by Dennis

[knocker]

Tonight's anomalies are more or less on the same page if differing in precise details.

Upstream some differences on the orientation of the Aleutian ridge but okay with the Canadian vortex and north American cold trough. Downstream the Atlantic fairly well amplified but differences exist on the orientation and intensity of the Atlantic ridge which will naturally have a knock on effect on the surface evolution. Certainly we will be looking at some transient wintry weather as systems swing south east around the ridge but the details of this will need to wait until a more definitive position of the ridge has been ascertained

The 10-15 period sees the vortex more organized with a trough in the western Atlantic, the GEFS not quite so keen on this with less ridging over the UK keeps the Atlantic upper flow flatter and more westerly than the more amplified NOAA and EPS. Essentially we are looking at a surface high over or adjacent to the UK for the period portending a dry interlude with temps a little below average but probably quite a diurnal variation. The only fly in the ointment may be the UK high diminishing late on the positive anomalies developing over Iceland and with the trough to our SE this leaves the door ajar to various interpretations

Edited December 29, 2016 by knocker

[bluearmy]

Yes Dennis, quite a snowy para days 8 onwards although thriugh week 2 it again goes cold zonal with snowfall associated with runners along the base of the upper trough. At odds with the mean anomolies on  GEFS and eps

[Memories of Feb '91]

Hey Guys.. First time poster but I've been viewing this forum since 2010. Although I'm in Ireland, just outside Dublin.. I always feel when the UK gets a cold snap from the East or North East, we are in with a chance too. I'm slowly learning to read the charts and I'm addicted to the ups and downs. Thanks to all the great contributors here, I've learnt so much. I really hope the UK gets a decent cold spell soon, you guys deserve it. If you have any of the white stuff to spare, send some over the Irish Sea in the form of streamers! Eyes down for the pub run.. Mine's a Guinness!

[East_England_Stormchaser91]

can hear the popcorn and Coke being munched on in here as the pub run is rolling out 

dare I say it, it's looking better. Firstly for New Year's Day into the 2nd and more digging south of the shortwave over NW Iberia! 

[Sky Full]

Just popped out for the day and came home to find....a new thread and 14 new pages of model discussion.  I thought, were they all just waiting for me to leave the room before having a proper chat?  That's a bit hurtful. 

And then I saw this:

j

and this:

And I thought maybe that's the reason....   But then I saw this:

and this 

and I had to go and have strong drink.

So I now know what the fuss is all about but do you have any idea how long it's going to take me to read all those new pages?  I'll be up half the night and I hope you're all satisfied.

 

 

 

[stewfox]

11 minutes ago, East_England_Stormchaser91 said:

can hear the popcorn and Coke being munched on in here as the pub run is rolling out 

dare I say it, it's looking better. Firstly for New Year's Day into the 2nd and more digging south of the shortwave over NW Iberia! 

First change i can see  (minor) is far north east at T96, cant seem to post charts at present maybe used by quota for the day

Edited December 29, 2016 by stewfox

[Man With Beard]

A bold D11-D18 on the EC monthlies tonight 

And D18-D25

If verified, no doubt it will be a below average month. Will it redeem itself for the mess it made of the "front loaded winter"? Surely can't be that wrong again???

 

Edited December 29, 2016 by Man With Beard

[blizzard81]

You have to admire the persistence of the gfs ops at the day 6 range. Very different to ukmo and ecm at that timeframe.

[Iceberg]

Seen enough for me upto t150. The high has build a touch further west, so happy with that and the associated cold plunge of snow it will bring over the next few frames.