Model output discussion - 21st Jan Onwards

[SLEETY]

ohh nice slider low inoming at 216

 

[BLAST FROM THE PAST]

 

Beautiful...cold for everyone and snow aplenty

 

 

Bournemouth primed to join in

 

JMA looking really good, more slow but after t192 it would become a stormer

 

BFTP

Edited January 27, 2016 by BLAST FROM THE PAST

[Purga]

Excellent chart @ 216hrs!

[Southender]

Very interesting @ Day 9.....

If we can get that split off lobe heading a touch further South, then we could be game on.

Ridge needs a bit more oomph as well.

Nice positive steps though.

Edited January 27, 2016 by Southender

[Frosty.]

It's worth mentioning that the Ecm 12z shows Saturday a cold and windy day with wintry showers and still cold in the north on Sunday...before next weeks excitement!

[Purga]

216hrs chart looks  very sexy on WZ format

Edited January 27, 2016 by Purga

[nick sussex]

Very exciting run from the ECM. All eyes probably on that shortwave which runs east develops and engages colder air coming down from the north.

The key thing here and its crucial is the weak low clearing eastwards this allows the upstream troughing to amplify and this then helps develop a ridge.

Its likely that some of the PV will want to start going back west later and you must have enough shortwave energy under any high as this happens to cut off the high and stop if from sinking as this happens.

[Southender]

Day 10....

[Eskimo]

Almost a carbon copy of the 00z output there. I'm not sure you can get two cold outliers in a row, however a lot of snow potential there!

[Mucka]

Exciting stuff.

Didn't expect tonight's ECM to repeat the dose much less improve upon this mornings run.

What is most encouraging is the consistency of the synoptic, is it a strengthening signal?

 

JMA and GFS quite different but at least JMA is going for southerly jet which gives more encouragement.

Edited January 27, 2016 by Mucka

[Purga]

Probably not too long lasting as heights to the north are getting squeezed out but a very nice run nontheless

[Frosty.]

Well what a fantastic Ecm 12z which is incredibly an upgrade on the stonking 00z....The UK would turn progressively more wintry next week with increasingly sharp / severe frosts, icy patches with many areas having  a good covering of snow! Winter to bite back?...I hope so. 

[karlos1983]

Oh my days, even the most optimistic of optimists could not have predicted that ECM 

If I had 1 complaint, could it please just be a little further south 

Edited January 27, 2016 by karlos1983

[snowray]

I must say that I did not expect the ECM to confirm its 00z output like this, really great run with lots of all the right ingredients going on there.

All we need now is to see is the GFS to start making small moves in the ECM direction. I would bank this run, could be lots of snow around, particularly Midlands Northwards, and maybe some interest for the South later on in the run.

[blizzard81]

4 minutes ago, Purga said:

Probably not too long lasting as heights to the north are getting squeezed out but a very nice run nontheless

I wouldn't be so sure about that. Pressure has fallen across Iberia and the azores high is well out to sea. Good chance the low developing on the southern tip of Greenland will zip south east through or even to the west of the uk with all the white joy that would bring

[nick sussex]

I've done a quick paint job on the ECM 120 and 144hrs outputs  to show the key features.

If you get to the ECM T144hrs then its literally impossible to not develop colder conditions.

 

All the outputs have that shortwave low you can see circled red, the key is that you have this separated from the troughing circled black at T120hrs.

At T144hrs you'll see the ECM clears this eastwards and develops those two lobes of high pressure circled blue, at this point you breathe a sigh of relief because its impossible for the upstream trough to phase with that shortwave low.

Because of the movement of the upstream pattern and that trough together with the split PV and the clearance of those purples over Greenland its now impossible to not develop some ridging to the n/nw because as the trough runs east it will develop WAA to the east to build positive heights near Iceland.

So if you get to the ECM T144hrs you essentially lock in the cold for several days.

In terms of the shortwave circled red and its track into the UK this if it verifies is liable to change given the timeframes. It will be effected by the strength of any ridge to the nw. A southerly track would correlate with a stronger high, more northerly weaker.

 

Edited January 27, 2016 by nick sussex

[winterof79]

How very 1983 esque

 

From raging westerly to something very wintry

 

[chris55]

After this mornings ECM and then seeing tonights UKMO it doesn't surprise me the 12z ECM delivered. 

Good agreement out to 144 with the euros tonight.

Will await the mornings runs with interest.

 

 

 

[Frosty.]

6 hours ago, Frosty. said:

I feel it's game on for a wintry spell next week.

I'm so glad the ukmo and especially the Ecm 12z backed up my earlier thoughts!..phew what a relief

[Singularity]

Nice one ECM, you've shown us how well a displacement of the vortex to our E/NE can work out if we can temporarily wall off the U.S./Atlantic lows.

Certainly the ECM trend over the past 24 hours is a great example of what happens when you have an increasingly large amplification signal becoming evident; Atlantic troughs start becoming negatively tilted and in some cases disrupting with sliding lows producing interesting scenarios.

Having UKMO poised to follow a similar route as of +144 is encouraging, but we must be wary of ECM's tendency to get a bit carried away with amplification signals. Today's adjustments coincide with the MJO moving out of the COD a few days ahead of when ECM was seeing, and in fact well in line with UKMO's recent projections:

To what extent this has influenced the strength of the ridge from the Pacific relative to the influence of the stratospheric events, I'm not sure to be honest. After all, GFS must have the MJO data fed in, yet hasn't produced such a strong ridge and subsequent Arctic High. So it could be more to do with the stratosphere and the extent to which a -ve NAM (Northern Annular Mode, basically the AO in the stratosphere) is able to influence the troposphere and encourage a -ve AO. This is an area of meteorological theory in which there has been much debate in the past few years, with competing theories jostling for position.

 

Longer term, ECM's +240 shows the vortex attempting to regroup in the Atlantic sector. This is well supported from above for the 11-14 day period as the strat. vortex drifts to the same location in response to a new bout of warming initialising in Asia. The Arctic High could help weak ridges to hang on in our vicinity though, which will be something to watch nearer the time.

Beyond that period, signs are the vortex will head back to where it will be in the 7-10 day period. IMO, that's when we see our biggest shot at a sustained cold pattern.

Essentially we have seen the broad 'cold Feb' potential come into focus as two separate opportunities, with a bit of a hiccup in between. Even I had begun to wonder about the first one as of yesterday morning but since then we have seen it placed firmly back on the table. Still need to see GFS come around before the brow can be wiped, though!

 

 

[Methuselah]

So what exactly has the ECM 'delivered'? Sorry to be a pedant, Chris, but only the real weather can deliver!

[nick sussex]

20 minutes ago, karlos1983 said:

Oh my days, even the most optimistic of optimists could not have predicted that ECM 

If I had 1 complaint, could it please just be a little further south 

Lol! At this range the track is likely to change depending on the pattern to the nw in terms of how much ridging.

Impossible to say where it will go at this range, even at T72hrs its still likely to change so if the ECM continues with this trend then its going to be a nailbiting wait for snowlovers in the UK.

[karlos1983]

1 minute ago, Ed Stone said:

So what exactly has the ECM 'delivered'? Sorry to be a pedant, Chris, but only the real weather can deliver!

Apart from hope, absolutely nothing yet, a bit like being a spurs fan I'd imagine 

[Methuselah]

Just now, karlos1983 said:

Apart from hope, absolutely nothing yet, a bit like being a spurs fan I'd imagine 

You couldn't have found a better analogy! 

[chris55]

29 minutes ago, Ed Stone said:

So what exactly has the ECM 'delivered'? Sorry to be a pedant, Chris, but only the real weather can deliver!

With 14000 (edit 33000 :-o) posts.........come on ed lol what do you think it delivered ....

It delivered a good 12z run....not actual weatherl. But this is model output and not current conditions eh

Edited January 27, 2016 by chris55