Model Output Discussion - 10th Jan Onwards

[ZONE 51]

Just read this, new out from Weatheronline it is interesting:

http://www.weatheronline.co.uk/cgi-app/reports?LANG=en&MENU=205&DAY=20140117

 

(link should be long range forecast)

[ZONE 51]

Not looking at the latest models, sharp temperature gradients over the N Atlantic fuelling strong depressions meaning further very unsettled weather with flooding issues & potential disruption due to wind.

Yes worrying that floods could continue, things have slowed down(weather systems/fronts) not good for the flooding situation but at least the stormy winds are eliminated from the pattern at the moment it's the last thing people need enough problems trying to free up the rivers of blockages from the trees holding back waters.

 

Jet winds now:

 

Jet at +144

Very much striking up power again, but a large high developing mid/east Atlantic (Azores)

Edited January 19, 2014 by ElectricSnowStorm

[Liam J]

Notable jet towards the final week of January, the storms aren't quite finished with us yet!

 

 

Some very intense members close to our shores.

 

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=1&ech=180

 

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=1&ech=192

Edited January 19, 2014 by Liam J

[ZONE 51]

Cold fans 'best' of the CFS:

 

[IDO]

The ECM op moving towards the last few GFS op runs. The Atlantic ridge unsustainable at around D9-10 as the main Canadian vortex moved towards Greenland:

 

 

Lets hope there is not a stalemate where the block prevents the vortex disrupting and instead it spills low after low towards the UK. We need it to just dissipate as quick as possible. Again on the ECM, like GFS the pattern for the upcoming potential cold shot is too far east:

 

 

 

GFS ensembles offer little for cold lovers with the FI uppers slowly on the rise and no mad cold runs:

 

 

 

At T264 on the GEFS, lots of spread: 

 

So we are no nearer knowing where the pattern change will take us and I assume ECM ens are also multi-clustered.

 

Still some interesting members at T264:  

 

  

 

 

 

But no cluster of eye candy runs that some have suggested will start showing up. In fact most members at T384 (FWIW) have a very flat zonal pattern with no HLB and the vortex still in all its glory. The mean: 

 

 

GEM showing the stronger Arctic high of ECM but again day 10 and the cold is too far east for us:

 

So despite the promise, we are still seeing the cold runs remain as a background noise that just does not want to become a trend.

Edited January 19, 2014 by i'm dreaming of...

[Radiating Dendrite]

Not a great ECM - we are left in no man's land again with poorer heights to the north and the azores high collapsing over us.

Hopefully just a poor run and not a new trend. Everyday is different on the models at the moment, some consistency would be most welcome!

[ZONE 51]

Not a great ECM - we are left in no man's land again with poorer heights to the north and the azores high collapsing over us.Hopefully just a poor run and not a new trend. Everyday is different on the models at the moment, some consistency would be most welcome!

Just hope models aren't going to be playing games with us for the next 2 months!!! 

Edited January 19, 2014 by ElectricSnowStorm

[winterof79]

GFS the only model not to build heights over the pole this morning??

http://modeles.meteociel.fr/modeles/gfs/runs/2014011900/gfsnh-0-144.png?0

http://www.meteociel.fr/ukmo/runs/2014011900/UN144-21.GIF?19-06

http://modeles.meteociel.fr/modeles/gem/runs/2014011900/gemnh-0-144.png?00

 

http://www.meteociel.fr/modeles/ecmwf/runs/2014011900/ECH1-192.GIF?19-12

[bluearmy]

ukmo at days 5/6 looks isolated (shame) but given the way that the modelling has been increasing the slp of the ridge whilst at the same time collapsing it se somewhat, it's not a complete shock. If upstream is a bit slower then this can happen.

ECM pulls an op straight out of its ens mean for its latter stages. again, no surprise to see this but one hopes the pendulum will swing back to the bigger -AO on the 12z's (and the ens).

Even this less impressive arctic block is a convincing vortex split by the end of the run and I am still pondering what happens to the Canadian vortex thereafter if that split holds. It can't behave like it has done for the past 8 weeks, that's for sure.

for the time being, the safe bet is a brief colder few days approaching month end and then back to transient ridges followed by troughing into Europe. that in itself is not without interest as if we still have trough disruption se, we will, by then, have a much colder continent to our se for any undercutting flow ahead of any conclusions.

This afternoons ukmo 12z is going to be eagerly awaited. If in the right area, it will change the modelling of the approaching Atlantic post day 6 as it cannot simply blast such a cold mass of air aside.

Edited January 19, 2014 by bluearmy

[Frosty.]

The outlook beyond 5 days, as ever is clouded in uncertainty, temperature wise at least but it looks like continuing unsettled as it has for the last 4-6 weeks but I remain positive that we will have occasional amplification with the formation of mid atlantic ridging with low pressure pushing far enough east to enable a rush of cold air to flood southeastwards at times with wintry ppn, ice & frost in among the wild, wet and windy spells and i'm certainly not ruling out a spectacular pattern change to full on wintry weather by early to mid february.

[Captain Shortwave]

Great UKMO this morning with cold air touching the east of the UK. The only solution I want as the models seem to be walking away from these major amplification events across the pole (GFS is still going backwards here and the ECM is starting to too)

GEM continues the long stand off between the cold and Atlantic airmasses with the cold just too far east and milder air only brushing the UK for a few hours before being replaced with cooler air from the north west.

Still all to play for, but I really want the UKMO to be onto something here.

[nick sussex]

I'll keep it short and not ramble:

 

GFS okay

ECM crxp

UKMO good

 

The later part of the ECM shows what can happen if theres not enough amplication upstream and the PV phases with troughing near the UK.

 

This isn't so much whether you can get some continental air in like the UKMO but the angle of the approaching low and also how far ne the Azores high has moved, and how far east the pattern is,the ECM is really so far east and so flat especially over the USA that the PV will just edge out into the Atlantic.

Edited January 19, 2014 by nick sussex

[Severe Siberian icy blast]

ukmo at days 5/6 looks isolated (shame) but given the way that the modelling has been increasing the slp of the ridge whilst at the same time collapsing it se somewhat, it's not a complete shock. If upstream is a bit slower then this can happen. ECM pulls an op straight out of its ens mean for its latter stages. again, no surprise to see this but one hopes the pendulum will swing back to the bigger -AO on the 12z's (and the ens). Even this less impressive arctic block is a convincing vortex split by the end of the run and I am still pondering what happens to the Canadian vortex thereafter if that split holds. It can't behave like it has done for the past 8 weeks, that's for sure. for the time being, the safe bet is a brief colder few days approaching month end and then back to transient ridges followed by troughing into Europe. that in itself is not without interest as if we still have trough disruption se, we will, by then, have a much colder continent to our se for any undercutting flow ahead of any conclusions. This afternoons ukmo 12z is going to be eagerly awaited. If in the right area, it will change the modelling of the approaching Atlantic post day 6 as it cannot simply blast such a cold mass of air aside.

I think for me that's the key there , Europe is about to go much much colder , not just Scandinavia/Russia like this week , we all know the models underestimate the strength of the block on many occasions and already we can see this scandi high is not going anywhere , for the last 3 days or so we have saw troughing over the uk , if France was cold then our weather would of been much different to what we'v saw , so I think once we can get Europe cold we may well be seeing much better weather at the surface . It concerns me somewhat regarding the strength of the Canadian vortex , the jet looks angry , and the Azores that I thought would be our friend and ridge north and block doesn't look to be modeled too much at the minute , at least we have a -AO setting up and know doupt that will continue to cause havoc with the output , we really need to see the vortex loosen its grip over the next 10 days but the Synoptics over America don't look favourable . But then given the strat warming coming then that should help distort further , feb really is make or break for our winter . . . .

[johnholmes]

I think John you have turned into a bit of a Grinch this year.  I think the only victim of models seems to be you. I haven't seen anyone hype it out of proportion, just some analysis on whats put infront of us.

 

Again, the only one taking it out of context is you.

 

FWIW, the ECM has been modelling the arctic high since the 00z 16 / 01

http://www.meteociel.fr/modeles/ecmwf.php?ech=72&mode=1&map=1&type=0&archive=1&mois=1&heure=0&jour=16&annee=2014

 

& its been gaining momentum since + traversing the ECM timelines across each daily as the models have run, to be consistent in the output @ 144 / 168 tonight.

 

This isn't just your run of the mill amplified atlantic ridge, its something more than that, a total reversal of the zonal wind @ 60N starting over the pacific & reversing around to Northern Europe by day 10.

 

The hurdles are clear in everyones mind that the UK is always the end of the line, bit at least allow people the fun of speculation, even if it doesn't arrive.

 

I just don't see the point of posting - It wont happen, its unlikely to happen, It cant happen- Yeah, thanks for that- we know that. We have known that for years.

 

Who cares.

 

S

 

Wheres the facepalm smiley.

 

The short term atlantic forecast shows no eastward movement of the low for the next 5 days.

 

your interpretation chum of the potential, and mine, both of us are entitled to our viewpoints. I asked why at 216h so much reliance on one model, not looked yet Steve but I will as it should be just a might closer if you are correct. Good for you if you are, time will tell who is the more realistic but for everyones' sake I hope it is you. Anyway I am off for my snow kick today so will leave you all in peace for 2 weeks.

[nick sussex]

I think this goes someway to explaining todays differences and also the more medium term impacts of what the models do with the ridge in the Pacific:

 

THE 500 HPA HEIGHT
ANOMALIES IN A FEW DAYS INDICATE A SIGNIFICANT POSITIVE ANOMALY
CENTER IS NEAR 55N IN WESTERN CANADA, WITH THE APEX OF THE RIDGE
IS CLOSER TO 75N NORTH OF ALASKA.  THIS LEAVES 35N AND 55N AS
POSSIBLE PATHWAYS FOR ANY ENERGY MOVING OUT OF THE PACIFIC TOWARDS
WESTERN NORTH AMERICA THROUGH THE RIDGE, DEPENDING UPON THEIR
POINT OF ORIGIN.  CONSIDERING THE AMPLIFIED TROUGH TO ITS WEST AND
HOW FAR NORTH THE PACIFIC SYSTEM IS EMANATING FROM, BELIEVE THE
NORTHERN PATHWAY, DIRECTED TOWARDS 55N/WEST-CENTRAL BRITISH
COLUMBIA, MAKES THE MOST SENSE.  HOWEVER, A FORMING SOUTHERN
CONSENSUS NOW CONSISTS OF THE 00Z GFS/00Z ECMWF AND THEIR ENSEMBLE
MEANS, WITH THE GEFS MEAN SOLUTIONS AS OF LATE FAR FROM
CONSISTENT.

 

You want the northern pathway and not the southern, and you can see if you look upstream that the UKMO is taking the northern one, also this:

 

THE HIGHLY-AMPLIFIED PATTERN ALOFT HAS ESTABLISHED A
QUASI-STATIONARY UPPER-LEVEL LOW OVER HUDSON BAY. FOR THIS TIME OF
THE YEAR...THIS IS NOT UNUSUAL--BUT THE IMPACTS CAN BE. THE MODEL
GUIDANCE IS IN VERY GOOD AGREEMENT WITH THE TROUGH IN THE
EAST...BUT IS STRUGGLING MIGHTILY WITH THE STABILITY AND
PERSISTENCE OF THE RIDGE IN THE WEST

 

If that ridge breaks down then this will kick the PV further east, that needs to remain amplified.

Edited January 19, 2014 by nick sussex

[cooling climate]

 

I think John you have turned into a bit of a Grinch this year.  I think the only victim of models seems to be you. I haven't seen anyone hype it out of proportion, just some analysis on whats put infront of us. Again, the only one taking it out of context is you.

Good post.I have not seen one post where anyone is saying deep freeze and raging blizzardsare on the way all we are saying is that a pattern change to something much more in linewith winter weather may be on the way.The GFS is less keen on Arctic heights this morning and the trouble sometimes with waveamplification and effects on the troposphere is that the models can react to quickly tothis although this is of course just one run. The ECM this morning tanks the AO as ithas consistently being doing the last few runs. As for the UKMO well what can you sayeveryone has moved on past the will it won't easterly except for the UKMO but since itson its own its probably best to ignore I think.

[IDO]

The extended 2m T for the Dutch Ens on ECM backing away from cold:  

 

The mean now around 5c from D6 where several days ago it was heading towards zero.

 

IMO that means that ECM members have been over-estimating the block to the NE, this run pushes the cold further east. There is no signal that we are heading for a cold spell on this ECM 0z suite, much like the 0z from GFS. This ties in with the latest CFS for London:

 

No cold for here throughout February.

 

So UKMO not looking to have much support for its 0z run. GFS probably (again) modelling the block the better on this mornings runs, ECM too progressive and UKMO too slow.

 

Things may change but there is no consistency cross-model for an Arctic high yet and the strat warming, if it amounts to anything (the PV still remains intact at T384) will not impact us till mid-Feb, leaving it very late for a cold spell.

Edited January 19, 2014 by i'm dreaming of...

[Stuie]

UKMO going for a NNW feed then leaning towards at an Easterly injection of cold it seems.

[Gibby]

Good morning. Here is the report on the 12 midnight outputs of the NWP for today Sunday January 19th 2014 lifted from http://www.norton-radstockweather.co.uk/Model-Analysis(2859336).htm

 

All models show the coming week as maintaining changeable conditions throughout for all. Today sees Low pressure out to the NW with slack pressure gradients across the UK giving rise to a lot of dry and bright weather with coastal showers in the West and South and frost and fog patches tonight. A similar pattern is shown for tomorrow so similar conditions can be expected. On Tuesday there will be a new trough moving slowly East off the Atlantic bringing rain, heavy in places and a freshening SSW wind. Wednesday too will see the rain still affecting the East of the UK while the West sees brighter and drier conditions with scattered showers as winds swing NW and pressure rises. Thursday sees a quiet day over the UK with slack conditions again with dry and bright weather for many with coastal showers in the West and rather cloudier conditions from an old decaying front in the East. On Friday an early frost will be followed by a dry and bright day as a ridge is shown crossing the UK from the West before increasing SW winds and cloud move in from the West at the start of the weekend with rain and freshening winds into Northern and western areas in particular to start next weekend.

 

GFS follows this period with little overall change for the rest of the run with spells of rain and brighter weather with showers alternating over the period. Low pressure will remain rampant crossing the Atlantic to the North of the UK and down over Europe. Temperatures as a result will remain close to average for all.

 

The GFS Ensembles today show no chance of anything cold at all as the majority of members show a rampant Atlantic with a strong Westerly wind blowing over the Atlantic with rain and showers carried across all areas at times with drier and brighter spells too at times, these especially in the South due to many members showing a strong Azores Anticyclone ridging towards the UK at times.

 

UKMO today finds the end of it's run with a deep Low pressure up near Iceland sending a strong WSW flow into the UK following Friday's ridge with increasing cloud and rain spreading East over the UK next weekend.

 

GEM today maintains a UK based trough driven by further Low pressure feeding in off the Atlantic with further rain at times for all in temperatures near to or a fraction below average.

 

NAVGEM shows an Atlantic flow next weekend and start to the new week with rain at times as troughs move East off the Atlantic in a Westerly flow.

 

ECM today also shows an Atlantic based weather pattern next weekend and the first half of the new week with West or NW winds sending alternating spells of rain and showers across the UK in a blustery wind at times. Temperatures will remain close to average but a little below at times in any NW feed following the exit of cold fronts.

 

The ECM 9 and 10 Day Mean Charts show Low pressure biased to be positioned to the North and NW of Britain and a strong Azores High with a West or NW feed bringing further rain at times for most in temperatures unlikely to be problematic for anywhere in the UK.

 

http://www.wetterzentrale.de/pics/Reem2161.gif

http://www.wetterzentrale.de/pics/Reem2401.gif

 

The Jet Stream continues to move across the Atlantic west of the UK and then turns South across Southern Europe via Spain. After this week it now looks the predicted strengthening will still take place steering it further East across the UK and then South over Europe as the High over NE Europe declines. It is then shown to move NE across the UK on a much more northerly track and on into Scandinavia by the end of the run this morning.

 

In Summary today the pattern remains very Atlantic based with little to suggest any shift towards anything wintry within the forecast period of the runs. All models show this week with a changeable pattern with alternating spells of rain mixed with drier and chillier spells with some night frost at times as Low pressure continues to move into the UK while weakening. High pressure will lie closer to the SW than for some time and this at long last will start to reduce and alleviate the surface flooding issues in the SW with time. In the second half of the run the weather will become rather windier with a longer Westerly fetch while maintaining the pattern of rain at times mixed with drier and brighter spells. Temperatures will remain close to average throughout with little or no chance of anything wintry.

[bluearmy]

Couple of observations on the ecm ens. First is that the spread on uppers makes the ukmo solution plausible. Looking through the stamps, about 20% possibility at best. that mean the 12z ukmo could be consistent but more likely not. Secondly, the building arctic ridge looks better supported by the ens days 7 through 9 (compared with recent runs) with potential ridging into greenland.

Thats the good news for coldies - the bad is the the next push of energy off the vortex at day 10 in a se direction is where the latter ecm ens have been trending and this will cut the arctic heights off as it spreads east across the n atlantic.

The spreads on uppers at day 10 shows a clustering bringing the atlantic well into the uk whilst those on heights give a big range of options with the jet headed anywhere on a clockface from 1 to 6 o'clock. Clearly, 4-30 would be good for us!

[TSNWK]

Hello. What is so postive about UKMO day 5 and 6 this morning, all I can see is the Azores high ridging in and an active vortex over Greenland.

Please can someone advise what might happen if and it's a big if I guess the UKMO verfied at D6.

Many thanks.

Edited January 19, 2014 by TSNWK

[Long haul to mild]

Awsome UKMO off the bat this morningAt day 6 today the atlantic front is hitting a brick wall & turning to snow in the E / NE./ SE

UKMO today finds the end of it's run with a deep Low pressure up near Iceland sending a strong WSW flow into the UK following Friday's ridge with increasing cloud and rain spreading East over the UK next weekend.Temperatures will remain close to average throughout with little or no chance of anything wintry.

Two knowledgeable and respected posters with vastly differing views at day 6. No wonder the rest of us are confused! Edited January 19, 2014 by Chalk Serpent

[IDO]

^^^ Thanks BA. The GEFS have been consistently saying no to next weekend's non-easterly and I thought we had got over this yesterday, till this morning's UKMO. However little support, so as you say an outside chance. The GEFS have now clustered (last two days) the D10 Atlantic Ridge as a sinker as the next wave of PV energy comes our way. It is good to hear that ECM are finally catching up with the GFS pattern for our region.

 

What happens next on the GEFS remains, like the ECM, varied, but the current main cluster is a stormy spell with a flatter flow (probably the GFS bias) so probably best to wait and see with regard to where we go from D12 +. So another two weeks of the Winter may go by to see if we can get a better pattern for cold, and waiting for a euro trough to run through the UK is not my ideal winter scenario as we can easily be on the wet side of that.

 

Its good to see that I am not the only one bemused by the ECM of late with sometimes it's whole suite amplifying the wrong pattern:

 

By Simon Keeling in Borth, Ceredigion 09:10hrs 19/01/2014
Temperature: 5.4  Weather: Sunny spells

Now I am frustrated! 

The ECMWF is really beginning to hack me off. 

Admittedly, other models have made errors too, but over the last couple of weeks the ECMWF seems to have gone from being the model of choice at medium ranges of 5 days or more, to an unreliable set of charts which occasionally predicts a hit of cold at days 9 and 10.  (source)

[bluearmy]

Two respected posters with vastly differing views at day 6. No wonder the rest of us are confused!

Martin perhaps hasn't looked at the uppers - it does look like its sinking away on the heights but I doubt the progress west to east of the Atlantic would be too easy.

[johnholmes]

no spin, no digs, everyone is entitled to their view, so let us all respect one another.

Simply posting what the anomaly charts at 500mb suggest this morning and last evening is the most likely upper air pattern. Simply accept or dismiss them but some reasons please for either.

My view on them is well known, reliable at about 70% IF they are consistent over time and with one another. The last week has shown no major differences between them and they consistently show as below.

http://www.meteo.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

http://www.cpc.ncep.noaa.gov/products/predictions/610day/500mb.php

 

My interpretation of them is this

Blocking well north and signals for +ve heights along with similar over the Atlantic, -ve heights shown in the 'middle' of the chart between the two +ve areas and ridges. The overall pattern suggests a fairly mobile Atlantic south of about 55N with the combined effect of the trough mainly east of the UK and the Atlantic ridge showing a flow at 500mb of north of west over the UK. With only minor changes this has been the prediction for much of last week. This seems the most likely upper pattern based on these outputs.

 

Just what they may show this time next week I am unable to say. It could be a fairly marked change of pattern with the block well north extending south, most likely if it did occur, from west of north. Or the block may stay where it is and the Atlantic continue to push systems towards the UK with the NE block tending to at least slow down their progress near the UK, they could be diverted into southern Europe. Or the block may retreat and the Atlantic become the major player. I simply do not know. The MJO forecats do suggest that the latter is the least likely IF that forecast is correct.

 

Too finely balanced in my view to go fully for any of the 3 possibles I have mentioned. Certainly an interesting time for model watching

Edited January 19, 2014 by johnholmes