Model output discussion 25th Jan - The final third of winter beckons..

[Timmytour]

1 hour ago, Man With Beard said:

Wont repost ECM monthlies as Nick has already done so, but just thought I'd mention how quickly it ditched its idea from last week to keep the Atlantic in the ascendency. Dreadful winter for the ECM monthly goes on, particularly past D15. Anyone differing risks me posting a ton of charts in reply proving it!

Also interesting how the 850hpa temp anomalies stay above average despite the Scandi High anomalies. D11-D15 could well see a return to the surface cold, then, rather than deep cold - but with a sinking jet, hopefully, and therefore snow becoming more possible.

I think Matt Hugo was a huge fan of the ECM monthly. As I recall a couple of years ago....after a few weeks of being advised it was advising a cold blast was in the way...I had the temerity to mention on Twitter that it might not be very good. Been blocked by Matt ever since!!

 

[snowray]

Chart of the day, GEM going bonkers.

[snowray]

GFS similar theme but everything a bit further south.

[NO LONGER POSTING]

What the bloody hell is the gfs 00z doing.. Sheez! 

Noticing something though on the models the current mild and wet spell keeps get watered further and further down with each run.. 

[jvenge]

35 minutes ago, snowray said:

GFS similar theme but everything a bit further south.

That will be colder in the ground than it looks from the uppers. I wouldn't be surprised to see ice days in the UK from that.

[snowray]

1 minute ago, jvenge said:

That will be colder in the ground than it looks from the uppers. I wouldn't be surprised to see ice days in the UK from that.

Maybe colder, but the GFS would be dry apart from a few wintry showers in the SE. GEM, on the other hand, would produce a nationwide UK snow event, look at them uppers moving in, some heavy snow in places and for a change not even remotely borderline, even on low ground what falls would be all snow

[Mucka]

36 minutes ago, snowray said:

Chart of the day, GEM going bonkers.

That's a real beaut!

Even better when you consider GEM hugely understates negative 850's!

 

 

[Argyle1980]

The UK jet stream! Certainly looking like the Atlantic it losing the fight here. Amazing charts .

[mb018538]

I wouldn't be at all surprised - I (and a few others) mentioned that the December zonal spell was modelled for eternity by the GFS etc, only to last for a few days. Same thing may be happening here - the models picked up the zonal signal, and for days ran with it out to 384 hours with no end in sight. In reality, we might get a week at best, before things really get interesting again. Some fantastic charts to see this morning!  SSW may be having some of the the desired effects after all!

[Ali1977]

Looking at the 144 charts of the big 3 the UKMO still looks best and slightly west with the Scandy high, it looks primed to unload the cold from NE Scandy and direct it our way. To be honest they all are encouraging and another trend towards colder weather. It now looks like late next week (earlier with UKMO) we should have a continental feed back, but unsure of its potency at this point. 

Edited January 31, 2017 by Ali1977

[Severe Siberian icy blast]

Ukmo looking very interesting thus morning with the vortex sethered in two and very cold artic air flooding south and West round the bottom of the high in scandi. Looks like we may be finally at a turning point in the winter! 6 the time lucky?!

[Gowon]

Again UKMO is better at 144hr over the north pole splitting the vortex.

 

[booferking]

Great runs this morning especially the uk model but i would like to see the azores high do one.

[shotski]

Slightly confused by the current model output, I was always under the impression that the polar vortex tends to more or less mirror the strat vortex and I was expecting to see a trough over Scandinavia and not the ridge of high pressure currently on offer. ???

 

[Seasonality]

1 hour ago, Surrey said:

What the bloody hell is the gfs 00z doing.. Sheez! 

Noticing something though on the models the current mild and wet spell keeps get watered further and further down with each run.. 

Actually it is a pretty cold run still for the UK. Got to expect chopping and changing at such a range. Interestingly, further east the last few gfs runs have had the op and the control as cold outliers leading the pack. Wish I could see the other models' ensembles to compare.

 

[Seasonality]

1 minute ago, shotski said:

Slightly confused by the current model output, I was always under the impression that the polar vortex tends to more or less mirror the strat vortex and I was expecting to see a trough over Scandinavia and not the ridge of high pressure currently on offer. ???

 

Hello Dave!

Not always. There can be a disconnect.

[Severe Siberian icy blast]

6 minutes ago, shotski said:

Slightly confused by the current model output, I was always under the impression that the polar vortex tends to more or less mirror the strat vortex and I was expecting to see a trough over Scandinavia and not the ridge of high pressure currently on offer. ???

 

The chart you posted is for 10hpa, which is at the very top of the strat, and although we have a strat warming from the top working it's way through to the lower parts of it, this immediate tropospheric pattern is tropospheric lead, not as a result of the warming at hand, which with the WAA from this into the artic is pinching the vortex on both sides (wave 2 type) as it filters up the troposphere into the lower strat.

Whether this is an immediate response to the warming is up for debate, I personally don't think it is because the warming in the upper strat hasn't worked it's way through yet imo.

[carinthian]

Morning encouraging chart from UKMO this morning. Its evolution post 144h will be likely to hold the Scandinavia/ Arctic high well north with eventual possible retrogress against the zonal flow in the later time span, which must be good for the UK. Low pressure over Euroland will help any advection of an Easterly towards the British Isles by 192h. As ever waiting for proper cold to hit the British Isles is as painful as prolonged toothache. This is your best chart of the season and hopefully not too late to save your snow barren winter. Will be interesting to see the 168t UKMO extended N Atlantic chart later .GEM also a  great run this morning, 

 c

[winterof79]

GFS not got a handle to our East yet....

 

[carinthian]

ECM looks a bit progressive this morning and sends Azores high towards Euroland- no Euro low on this runs which is not good to see, however, the pressure pattern synoptic forecast looks all wrong to me especially over the continent..

 C

[That ECM]

3 minutes ago, winterof79 said:

GFS not got a handle to our East yet....

 

Past t120, I don't think any of them have with so much going on. As frustrating as it is we will have to watch for awhile and let it unfold. 

[Ali1977]

Models all slightly different beyond day 4/5 which significantly change how the block effects the UK - UKMO looks good at 144 and should be v good beyond, and the GEM doesn't split the PV but gives us a great Scandy high with a cold blast from the East. GFS and ECM still to Far East with the attempted split.

Still a few days away before we know where things may lie by mid next week.

Can we trust this headline - mmmmm no!!! But exiting model watching this week all the same.

[bluearmy]

Ecm taking the long way to paradise and TBH, hasn't looked too keen on being progressive re any deeply cold flow 

could be quite a bumpy ride considering the stakes are high, given that this is february (especially so for the south) 

 

[Nick F]

2 hours ago, jvenge said:

That will be colder in the ground than it looks from the uppers. I wouldn't be surprised to see ice days in the UK from that.

Certainly chilly in the easterly flow on GFS day 9-10, though dry

Still some uncertainty re: a few potentially troublesome lows arriving from the SW towards southern UK Friday and Saturday, GFS and ECM both have a low centre moving across England/Wales Friday evening, then another low moves through the English Channel/ N France on Saturday.

T+90 GFS v EC

T+108 GFS v EC

00z ECM tracks the 1st low further N than GFS on Friday - it is at its deepest phase to the SW before it fills across the UK, 00z GFS doesn't really develop it much. Saturday's low a more similar track and depth though, despite 24hrs later, and looks to be more of a problem from the heavy rain so soon after Friday's low

Certainly need watching ...

[MR EXTREMES]

can i please bank the gem

ecm has juicy displaced azores heights plus scandi heights oooooo can we come up trumps this time lol