Model Output Discussion 17th Dec.2013-12z onwards.

[SMU]

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

 

Whilst not the Classic screaming Easterly maybe we hoped for - the cold surface air is already wedged into the UK-

 

The Atlantic low has stalled after hitting the buffers which means the only way the jet can travel is up & down.

 

That low would send more energy underneath & the core would fade Northwards-  leaving some snow over the UK.

 

It will be interesting the T2M debilt temps & day 10 on the operational V the Means tonight.

 

S

[IDO]

For the last few days the 12hrs of both the ECM and UKMO have been more amplified than their 00hrs runs. Let's think positively the 12hrs on Boxing Day would have more airplane data than Xmas Day!

 

Even with some sort of stalemate there could be some snow along the boundary, I think we need to hope for some westwards corrections and stronger ridging into eastern Greenland earlier.

 

Even putting aside the recent ECM FI bias both it and the UKMO have potential at T144hrs.

 

Hi

 

My concern is that there is not one GFS member at T168 that supports heights close to Scandinavia!

 

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=6&ech=168

 

The GFS mean at T168:  This morning's ECM mean at T192: 

 

Zero support. Hoping this is not one of those ECM over amping it runs. I did say yesterday that I was expecting some, as the Control (Christmas Eve) had the PV entering Cuba on one of its runs (D15). Wait and see what the mean says.

[Man With Beard]

Very encouraging for cold prospects regardless of what happens in this particular episode. The problem all winter has been getting HLB to form. Signals have been consistent over the past few days, from all models, that heights will form to our north in the 7-10 day timeframe. This means the PV has lost its "sole dictator" status on the weather pattern and that is good news for cold opportunities. It may be close but no cigar this time, but it is often the case that once there has been one attempt at HLB, more attempts follow shortly after. My guess is a good chance of a proper cold spell in the next 3 weeks.

[karyo]

Hi

 

Zero support. Hoping this is not one of those ECM over amping it runs. I did say yesterday that I was expecting some, as the Control (Christmas Eve) had the PV entering Cuba on one of its runs (D15). Wait and see what the mean says.

I think the ECM is overdoing the Scandi high but either way the jet is too strong and unwilling to go under. As soon as energy starts coming over the high, it will make the high sink especially as there is not sufficiently deep low pressure over the Med.

 

If the jet was weaker then maybe but as it stands I cannot see much promise from this. As soon as the high sinks it becomes a hindrance again as it reinforces the high pressure over the continent and then we have southwesterlies.

 

Karyo

[bluearmy]

Again we have an op out of kilter with its general mean. guess these arctic height rises and their interaction with the jet plus the weaker height bubbles being shoved up there are causing issues. This morning ecm overdid the azores ridge in fi, this evening its the scandi. Will be interesting to see if the ens/anomolys stay rock solid.

[Cheese Rice]

Eurgghhh I'm all for heights building but can't say I'm too enamoured at height rises to our NE, more often than we not just miss the cold pool, just look at Feb 2012 as an example. 

Edited December 26, 2013 by Cheese Rice

[Grimsby Snow Lover]

Eurgghhh I'm all for heights building but can't say I'm too enamoured at height rises to our NE, more often than we not just miss the cold pool, just look at Feb 2012 as an example.

So true, but Feb 1991 was a thing of beauty.

[Gibby]

Good evening. Here is the latest report on the Boxing Day Evening 12 noon reports for today December 26th 2013.

 

All models show a deepening Low pressure moving ENE close to Northern Scotland tomorrow with a strong Westerly flow across Britain. With heavy rain crossing quickly East overnight clearing through the morning it's a mix of sunshine and showers for the rest of tomorrow and Saturday before a ridge crossing East on Sunday drier things up briefly before cloud and rain spills back NE late in the day.

 

GFS then shows the last two days of 2013 as very unsettled with Low pressure up to the NW steering troughs NE across Britain with further rain at times in a blustery but less strong than of late SW wind. New Year 2014 shows little change in the overall pattern with wind and rain continuing to feature regularly over the UK as depressions cross the UK from the West or NW. With time some short colder interludes with more in the way of wintry showers is possible with a Northerly flow at the end of the run giving the UK the best shot of sleet and snow showers for a time as High pressure builds close to the SW.

 

UKMO closes tonight's run with Low pressure out to the West with a South or SW flow across the UK with rain or showers at times in temperatures close to average.

 

GEM also shows a very zonal pattern persisting with High pressure well to the Southwest and a succession of Low pressure areas continuing Eastwards to the North of the UK throwing trough after trough across the UK with rain and showers at times in average temperatures.

 

NAVGEM also show the same zonal synoptic setup with Low pressure areas to the North of the UK repeatedly bringing wet and windy weather across the UK with rain and showers for all in average temperatures.

 

ECM tonight shows a short battleground scenario between troughs of Low pressure moving in from the West against a High pressure block to the North and NE. This seems temporary as the Atlantic Low pressure bandwagon train seems too strong coupled with a strong Azores High pressure area which on this occasion overpowers any blocking to the NE.

 

The GFS Ensembles show little support for any major pattern shift anytime soon. There is support for the Jet Stream to flow more SE over Europe and this may allow some longer colder interludes to affect many parts of the UK later in the period.

 

The Jet Stream forecast continues the flow in it's general current location for the next week or so before it is shown to move South particularly at the European end with some cold pooling possible over the UK later.

 

In Summary there is very little support for anything desperately cold within the next couple of weeks with the general consensus being for a continuation of the unsettled and rainy weather with colder conditions with sunshine and showers at others. With a strong Azores High we are left to look for conditions over Europe at the moment to produce something that could end the current unsettled Atlantic spell and though there are some hints of that happening on some runs tonight any success is likely to be thwarted by an over riding Jet flow and the Azores High as illustrated at the end of the operational run from ECM and the far end of GFS though admittedly from rather different situations to one another.

 

[nick sussex]

Hi

 

My concern is that there is not one GFS member at T168 that supports heights close to Scandinavia!

 

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=6&ech=168

 

The GFS mean at T168: gensnh-21-1-168.png This morning's ECM mean at T192: EDH1-192.gif

 

Zero support. Hoping this is not one of those ECM over amping it runs. I did say yesterday that I was expecting some, as the Control (Christmas Eve) had the PV entering Cuba on one of its runs (D15). Wait and see what the mean says.

Yes the ECM has been less than reliant in recent weeks and hardly one to trust at 168hrs onwards but here the crucial difference in its output begins at T120hrs, the UKMO is midway between the ECM and the GFS, the GFS has least cold potential.

 

Hopefully we'll know in the morning which model has got this one right.

Edited December 26, 2013 by nick sussex

[cooling climate]

 

Eurgghhh I'm all for heights building but can't say I'm too enamoured at height rises to our NE, more often than we not just miss the cold pool, just look at Feb 2012 as an example.

Many in the parts of east Anglia and the southeast saw laying snowin Feb 2012.Was just thinking that if the GFS is slightly to far west in trying topush heights towards Greenland and the European runs slightly to far eastwe could be in prime position.Plus if the runs show the high to be in the perfect position at t240 andyou know the output will change as the timeframe gets closer you invarablyfing the block in the wrong position by t0. Therefore if the models arecorrect with a block forming to the northeast (that would be my punt) thenhopefully over the next few days we will see the block orientate to a muchbetter position for the UK. Edited December 26, 2013 by cooling climate

[Panayiotis]

Eurgghhh I'm all for heights building but can't say I'm too enamoured at height rises to our NE, more often than we not just miss the cold pool, just look at Feb 2012 as an example. 

Yes but January 2013 is an example of what easterlies can bring, check the charts between the 17th to the 22nd. Brought 5-10cm of snow here!

[SMU]

http://www.meteociel.fr/modeles/ecmwf/runs/2013122612/EDH0-240.GIF?26-0

 

ECM MEAN tonight very good at 240- also from day 9 to 10 the cold over Europe advances west which it cannot do unless its being forced, also this wouldn't be the case if there is no block.

 

All in all a good day for the euros.

 

S

[Methuselah]

 

All in all a good day for the euros.

 

Even more so, should they turn out to be correct...

[Cloud 10]

http://www.meteociel.fr/modeles/ecmwf/runs/2013122612/EDH0-240.GIF?26-0

 

ECM MEAN tonight very good at 240- also from day 9 to 10 the cold over Europe advances west which it cannot do unless its being forced, also this wouldn't be the case if there is no block.

 

All in all a good day for the euros.

 

S

 

Nice to see the removal of those red 850 temp. anomalies to our NE on those mean charts

as well.

 

72hrs..  240 hrs..

 

 

Can the cold pool be coaxed far enough westward to affect the UK though?

[Man With Beard]

ECM mean at T144 and T168 suggest Scandi high may be a possibility I think?

[winterof79]

http://www.meteociel.fr/modeles/ecmwf/runs/2013122612/EDH0-240.GIF?26-0

 

ECM MEAN tonight very good at 240- also from day 9 to 10 the cold over Europe advances west which it cannot do unless its being forced, also this wouldn't be the case if there is no block.

 

All in all a good day for the euros.

 

S

Yes at 144z the mean is not far off the UKMO

http://www.meteociel.fr/modeles/ecmwf/runs/2013122612/EDH1-144.GIF?26-0

http://www.meteociel.fr/ukmo/runs/2013122612/UN144-21.GIF?26-18

 

The zonal train may be about to hit the buffers

http://www.meteociel.fr/modeles/ecmwf/runs/2013122612/ECM1-168.GIF?26-0

Edited December 26, 2013 by winterof79

[tinybill]

i know  its a  long way off  think we  better  keep a  eye on mondays storm

[SMU]

http://www.knmi.nl/exp/pluim/vijftiendaagse/index.php?run=12

 

Updated extended ECM ensembles show a further drop off between 11-15 over & above the 00z.

 

Theres even the 1991 run thrown in for good measure!

 

 

S

[Summer Sun]

Once again the ECM Op run is another outlier at the end

 

Op

 

 

Ensemble

 

[I remember Atlantic 252]

Once again the ECM Op run is another outlier at the end

 

Op

 

 

Ensemble

 

 

Always giving christmas cheer eh Gavin D? I know you love storms, rain and Atlantic air

 

only mucking around really Merry Xmas!!

[winterof79]

http://www.knmi.nl/exp/pluim/vijftiendaagse/index.php?run=12

 

Updated extended ECM ensembles show a further drop off between 11-15 over & above the 00z.

 

Theres even the 1991 run thrown in for good measure!

 

 

S

Yes i can imagine the forum.....endless zonal muck raging PV..etc...etc

http://modeles.meteociel.fr/modeles/reana/1991/archivesnh-1991-1-10-0-0.png

 

Then a mucky high slap bang over us

http://modeles.meteociel.fr/modeles/reana/1991/archives-1991-1-13-0-0.png

whatever next.....

 

http://modeles.meteociel.fr/modeles/reana/1991/archives-1991-1-17-0-0.png

 

Just for feb 1991

http://modeles.meteociel.fr/modeles/reana/1991/archives-1991-2-7-0-1.png 

Edited December 26, 2013 by winterof79

[Grimsby Snow Lover]

Once again the ECM Op run is another outlier at the end

 

Op

 

 

Ensemble

 

Forgive me if I am reading them wrong but they don't look that different considering there are over 51 runs averaged out.

[bluearmy]

the ecm op isnt a complete no no as would be the case with an outlier. however, it looks very doubtful that the scandi high will establish so far west as on that run by day 10.  the ecm extended ens remain bang in line with prior output. if anything the troughing into europe getting deeper by the run. we find the jet blasting through the med in a fortnight. i am truly baffled by comments made by forecasters (if reported accurately) this morning. granted that we may end up with the troughing passing nw/se just to our east which will just be chilly and wet. however, a correction west of a few hundred miles in two weeks is nothing and would leave swathes of the country under deep snow. seems little chance that much of the continent will avoid a thick white cover by mid jan.

 

the gem ens beginning to smell the coffee on this one but too many of them keeping the jet on a more sw/ne bias in week 2.  gefs doing a decent job (as charts posted this morning showed) but still not showing anomolys as deep as ecm. the 32 dayer due out soon - until mogreps-15 falls into line with this line of thought, exeter wont jump. in my experience,  mogreps-15 takes time to get onboard a change. there is a chance it is right and ecm ens are not. however, the way the gefs are trending, i suspect it will come on board. i guess ian must be on holiday. could do with him coming back soon !!

[Summer Sun]

the ecm op isnt a complete no no as would be the case with an outlier. however, it looks very doubtful that the scandi high will establish so far west as on that run by day 10.  the ecm extended ens remain bang in line with prior output. if anything the troughing into europe getting deeper by the run. we find the jet blasting through the med in a fortnight. i am truly baffled by comments made by forecasters (if reported accurately) this morning. granted that we may end up with the troughing passing nw/se just to our east which will just be chilly and wet. however, a correction west of a few hundred miles in two weeks is nothing and would leave swathes of the country under deep snow. seems little chance that much of the continent will avoid a thick white cover by mid jan.

 

the gem ens beginning to smell the coffee on this one but too many of them keeping the jet on a more sw/ne bias in week 2.  gefs doing a decent job (as charts posted this morning showed) but still not showing anomolys as deep as ecm. the 32 dayer due out soon - until mogreps-15 falls into line with this line of thought, exeter wont jump. in my experience,  mogreps-15 takes time to get onboard a change. there is a chance it is right and ecm ens are not. however, the way the gefs are trending, i suspect it will come on board. i guess ian must be on holiday. could do with him coming back soon !!

 

He's still around on twitter: https://twitter.com/fergieweather

[SMU]

A step towards the EUROS on the 84 GFS- the pattern is a way back & more amplified- although possibly not a full swing back- 

 

S