Model output discussion - 7th January onwards

[Ali1977]

Everything further west at 120, much better than GFS with the ridge.

Edited January 12, 2019 by Ali1977

[Methuselah]

Considering the number of mouthwatering charts that keep oozing out, it's like a mausoleum in here today!

[Frank Trough]

2 minutes ago, Mike Poole said:

Too many underreactions today!! 

Classic run from FV3, T384 snow chart, just for fun, obviously.

I honestly can't see what's not to like, even the GFS 6z, it got there in the end didn't it?

The worry with this SSW compared to the Feb 18 one was whether this time the pieces would fall conducive to UK cold.  Barring every single model being wrong, they have fallen conducive.  So we move on...

The SSW is a major one, with prolonged wind reversal in the strat.  And with ECM 46, very latest GloSea5, and CFS all going for significant high latitude blocking for weeks if not months in the case of GloSea5, the effects will be long term, so - breathe - and let the snowiest half of winter in living memory unfold!

If the FV3 was correct we would have already had freeze. Christmas would have been seasonal.

i would ignore it for now.

[Ice Day]

ECM / UKMO / GFS / GFSP at 120hrs. UKMO, ECM and GFSP are a pretty good match I'd say! GFS looks to be too flat

      

[ICE COLD]

Mmm yer liking ECM T120 . 

[kumquat]

C'mon ECM give it some welly!

[Ali1977]

1 minute ago, kumquat said:

C'mon ECM give it some welly!

Very close the the UKMO and the UKMO 144 looked v good - we shall see.

[Skyraker]

3 minutes ago, Certain kind of fool said:

If the FV3 was correct we would have already had freeze. Christmas would have been seasonal.

i would ignore it for now.

I don’t remember the fv3 modelling anything seasonal in December.

 

Perhaps you have a chart to jog our memory.

[MidnightSnow]

1 minute ago, ICE COLD said:

Mmm yer liking ECM T120 . 

This chart is nailed. M4 boundary in full force.

[Ali1977]

ECM holding onto the cold air we’ll.

 

Edited January 12, 2019 by Ali1977

[frosty ground]

7 minutes ago, Ed Stone said:

Considering the number of mouthwatering charts that keep oozing out, it's like a mausoleum in here today!

It’s a rather odd place at times 

[Mike Poole]

OK T144, similar to UKMO but we get to see where this one goes next...looks good!

Edited January 12, 2019 by Mike Poole

[SMU]

ECM has -7c in London @144 with an acute slider ( west country )

feeling very cold --

[ICE COLD]

Yep think we will take that ECM

[northwestsnow]

Looks good at 144 ...

LOW should head into europe..

[WhiteFox]

On the question of confidence regarding an upcoming cold spell, it's worth looking at the 500mb height anomaly charts. First, the 6-10 day charts shows above average heights off the Eastern seaboard of the US, stretching to mid-Atlantic, with weaker anomaly heading heading towards Greenland. We have below average anomalies to our East and North-East. It would seem to me (although a more trained eye could read it better)  that this corresponds to a NW to SE flow. The 8-14 chart maintains the general theme of higher anomalies to the West and lower to the East, although higher anomalies are slightly further west which may indicate that the upper trough to the East has more influence on the UK. 

Now, I haven't seen them for the past few days, so I'm not sure about consistency, but so long as we see such anomalies forecast, it's not worth getting too worried about details at the surface which will change markedly from run to run.

 

[Cheshire Freeze]

1 minute ago, northwestsnow said:

Looks good at 144 ...

LOW should head into europe..

The parent low S tip of Greenland has a +ve tilt though...

[nick sussex]

What a thriller !

At day 6 no agreement between the big 3 upstream over the USA with shortwave energy  , downstream over western Europe and over the east Pacific .

[Rocheydub]

168 looks cold in situ. Not sure where it’s going after though!

[ICE COLD]

Still pretty cold at 168 . 

[Mark wheeler]

168 Hours looks Great to my untrained eye .

[Cheshire Freeze]

Unlike the 0z we want energy pulled SE through the UK here to prevent the Azores HP nosing in with the jet looping over the top. We want the Hp building in behind instead

[Captain Shortwave]

Eastern areas becoming very cold with the arctic air remaining as well as a light flow developing off the continent, that colder denser air is important in the hope of fighting back against whatever comes in from the west. Quite tight on the upstream evolution, there is probably enough there to allow the low heights over Greenland to bleed south east rather than pushing away that weak high.

Day 8 is good enough, that low has had the sting taken out of it and is looking like dropping through the UK whilst retaining an airmass cold enough for snow with pressure rising in the Atlantic.

Edited January 12, 2019 by Captain Shortwave

[gottolovethisweather]

1 hour ago, carinthian said:

UKMO again consistent with its output and this is the best model so far for the route to cold in the short term. Looks like the low at the end of the week to track over Ireland and sinking towards Brittany and introducing a easterly component to the flow over Southern Britain next weekend.  We need to see ECM go down this route this evening.

 

C

Could well be the start of a pattern reset, I'd say with the Atlantic dead as a dodo. Northeasterly and Easterlies much more prevalent as we head deeper into the backend of January. I believe this signal will show up even stronger in the modelling as next week progresses as the ensembles (especially at the beginnings of FI and beyond) spreads have already hinted at the possibilities from time to time. I'm certainly happy that no drastic turnarounds have turned up in the often oh so irrelevant weekend outputs and that the COLD is on target.

[Purga]

12z GEFS improved greatly

00z                                                                06z                                                          12z

 

Notice the uptick to less cold in the 00z/06z has gone - so the cold has longevity.