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


Paul

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Posted
  • Location: Aviemore
  • Location: Aviemore

Time for a fresh thread, as the final third of winter closes in. 

Please keep posts model related in this discussion - and head over to the model banter thread for emotional reactions to the models/weather, ramps, moans and general chat..

All charts/date can be found here on Netweather:

NetWx-SR (Hi-res short range)
http://www.netweather.tv/index.cgi?action=netwx-sr;sess=
 
NetWx-MR (Medium range)
http://www.netweather.tv/index.cgi?action=netwx-mr;sess=
 
GFS
http://www.netweather.tv/index.cgi?action=nwdc;sess=

GFS Para
http://www.netweather.tv/index.cgi?action=gfspara;sess=

GFS vs GFS Para
http://www.netweather.tv/index.cgi?action=gfscomp;sess=
 
Ensembles
http://www.netweather.tv/index.cgi?action=ensviewer;sess=
 
ECMWF
http://www.netweather.tv/index.cgi?action=ecm;sess=
 
ECMWF EPS
http://www.netweather.tv/index.cgi?action=ecmens;sess=
 
Met Office Global
http://www.netweather.tv/index.cgi?action=meto;sess=
 
Met Office Fax
http://www.netweather.tv/index.cgi?action=charts;type=fax;sess=
 
GEM
http://www.netweather.tv/index.cgi?action=gem;sess=
 
Model Comparison
http://www.netweather.tv/index.cgi?action=modelcomp;sess=

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Posted
  • Location: Scarborough, North Yorkshire
  • Location: Scarborough, North Yorkshire

Have to agree. With the odd wobble the UKMO has to be respected and has been very consistent this winter. Has been a strange winter to call with all the varying signals.

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Posted
  • Location: Darlington
  • Weather Preferences: Warm dry summers
  • Location: Darlington

UKMO extended looking windier and for some wetter as we move into the final month of winter

ukm2.2017020112.168.lant.troplant.prp.fcst.gentracker.png

ECM and GFS don't agree with UKMO though they keep the low further away

ecm2.2017020112.168.lant.troplant.prp.fcst.gentracker.pnggfs2.2017020112.168.lant.troplant.prp.fcst.gentracker.png

 

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Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth
9 minutes ago, on the coast said:

Have to agree. With the odd wobble the UKMO has to be respected and has been very consistent this winter. Has been a strange winter to call with all the varying signals.

I would add the GEM. Bearing in mind it goes out to T240. No easterly nonsense at all, but got on board for the mini-arctic break of a couple of weeks ago. 

A good little test for it coming up, though - it's been fairly bullish about dropping the jet south a touch - northern areas could get on the right side of the polar front if its recent runs are correct:

gem-0-240.png?12

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Posted
  • Location: Eastbourne and Larnaca,Cyprus .
  • Location: Eastbourne and Larnaca,Cyprus .

Regarding Tamaras and Singularitys posts . The MJO NCEP update discusses that destructive interference with the MJO should lessen in week 2  and we might see this replaced with constructive interference enhancing the MJO signal. This of course is just a forecast so best not get ones hopes up as I think we're all reaching into our model interest reserves to see out the winter. 

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Posted
  • Location: Windermere 120m asl
  • Location: Windermere 120m asl

Oh dear its all gone very quiet in here this evening, the lows of Monday, the highs of yesterday, and back to the lows of today - all typical of the MOD thread it seems. 

What are they showing - a theme of unsettled conditions setting in as we move through the weekend and more significantly next week,  the jet will be taking a more flatter westerly trajectory, but also signs that it will be more southerly placed than recent weeks and may still come unstuck...

There is a suggestion the alantic frontal system due to move in on Monday could be quite negatively tilted, struggling against the block.. I say reliable timeframe is Monday at best, indeed some form of channel runner is being forecasted, and a bit of a messy slack airstream to its north.

(I felt I needed to post something to keep this thread alive and wake people up..)

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Posted
  • Location: South Essex
  • Location: South Essex

I suspect its more stunned silence than anything else. GFS rolling out now is something of a horror movie. Its a Bartlett set up tbh. Of course may not happen like, but pretty grim tbh.

 

 

Edited by Jason M
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Posted
  • Location: st albans
  • Location: st albans

Latest day 5 FAX is interesting as it has a disruptive look about it and certainly builds the ridge ahead more than today's runs have

It is not taken from the ukmo run

as far as mondays front bringing anything wintry is concerned, thicknesses look much too high, even on that more interesting FAX 

 

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Posted
  • Location: Santry, Dublin, Ireland. 50 metres ASL.
  • Location: Santry, Dublin, Ireland. 50 metres ASL.

As long as the jet stream is acting in this buckled manner, anything is possible.

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=192&mode=5

I'm not hopeful at all, but I'm still keeping a watchful eye.

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Posted
  • Location: frogmore south devon
  • Location: frogmore south devon

I think after all that came out of the GFS, ECM, GEM. and every other model and then the UKMO is right on every turn of the dice it we have it in our power to follow the one model thats why it is quite on here to night 

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Posted
  • Location: North East Hampshire
  • Location: North East Hampshire
22 minutes ago, Jason M said:

I suspect its more stunned silence than anything else. GFS rolling out now is something of a horror movie. Its a Bartlett set up tbh. Of course may not happen like, but pretty grim tbh.

 

 

It's a poor run, but let's not kid ourselves  - it's nothing like a Bartlett set up.

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Posted
  • Location: Peterborough N.Cambridgeshire
  • Location: Peterborough N.Cambridgeshire
21 minutes ago, bluearmy said:

Latest day 5 FAX is interesting as it has a disruptive look about it and certainly builds the ridge ahead more than today's runs have

It is not taken from the ukmo run

as far as mondays front bringing anything wintry is concerned, thicknesses look much too high, even on that more interesting FAX 

 

You'e certainly right BA and in my experience it's unusual for the fax to be modified as much as it has been.

Must admit as I found the change in the output yesterday morning baffling I equally find the change in todays output equally baffling.

I wouldn't be surprised if we see more drama yet.

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Posted
  • Location: South Essex
  • Location: South Essex
14 minutes ago, Johnp said:

It's a poor run, but let's not kid ourselves  - it's nothing like a Bartlett set up.

Nope not kidding, its a Bartlett set up. Persistent band of high pressure to our SE. Its not exactly the same as the 1988 version of course and as said above it might not happen like that, but IMHO the 18z is a Bartlett set up (much like most of Dec tbh).

Your perfectly entitled to a different view but in terms of the weather we experience its splitting hairs.

Edit: Control going the same way, albeit still just enough variation in the GEFS to just leave a little doubt this evening.

 

Edited by Jason M
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Posted
  • Location: Santry, Dublin, Ireland. 50 metres ASL.
  • Location: Santry, Dublin, Ireland. 50 metres ASL.
7 minutes ago, Jason M said:

Nope not kidding, its a Bartlett set up. Persistent band of high pressure to our SE. Its not exactly the same as the 1988 version of course and as said above it might not happen like that, but IMHO the 18z is a Bartlett set up (much like most of Dec tbh).

Your perfectly entitled to a different view but in terms of the weather we experience its splitting hairs.

Well, technically, he's correct, it is not a Bartlett. It doesn't matter if it produces the same weather for us, it's still not a Bartlett.

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Posted
  • Location: South Essex
  • Location: South Essex

Hi Rochey,

The term Bartlett was an internet forum invention and doesn't actually exist in meteorological text books. See below description lifted from the web...

However, in recent years (this written in autumn, 2005), these situations have been notable by their absence. What 'high' blocks there have been stay teasingly just too far east and more often than not, a broad band of high pressure extends from the Azores area, east-north-eastwards towards the Biscay / English Channel region - perhaps now & then displaced towards the Alps, as storm upon storm sweeps in from the North Atlantic, hurried along by an often powerful upper jet (see "What are jetstreams?"). Rain, gales and above average temperatures prevail, with any 'wintry' weather confined to brief incursions of Polar Maritime west or WNW'lies, or perhaps a temporary Arctic Maritime blast from the north - which is shunted away as the next surge of mild air hurries in from the west. The apparently semi-permanent belt of high pressure in the 'wrong' place has been christened ... "The Bartlett High", in honour of Paul Bartlett, a luminary of this ng, who used to put his experience of forecasting to the test by publishing a reasoned winter forecast for all to see. As Les Crossan has noted (also a stalwart of this ng), this has come to be regarded as a 'slug' - nothing moves it, not even extracting a pair of dividers and skewering the said beast as it sits dominating any particular synoptic chart!

In essence I'm just using the term to describe a particular set up a bit like the 'Murr sausage' (I still shudder at that one :rofl:). If you had said no such thing exists you would have been technically correct, however you and Johnp seem to be suggesting that a Bartlett is something else which is puzzling?

Anyway, things must be bad when this is being debated, so lets all just agree to disagree :D. Hopefully things will change and I can describe it as a 'displaced Bartlett' (always wanted to use that!).

 

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Posted
  • Location: Rotherhithe, 5.8M ASL
  • Location: Rotherhithe, 5.8M ASL
8 minutes ago, Rocheydub said:

Well, technically, he's correct, it is not a Bartlett. It doesn't matter if it produces the same weather for us, it's still not a Bartlett.

GFS 18z is very cyclonic a continual theme we see very cold air spilling out across the pond reinvigorating the Atlantic & the jet stream. For the British Isles pressure hits the ceiling at 1015mb through the entirety of the GFS 18z, not even near anticyclonic, jet stream largely head on or to the S of us, I suppose with some more adjustments there is a risk of northern areas being on the "right side". Quite frankly the assertion of a Bartlett is misleading. Hp to SE is fairly transient definitely not entrenched. Scottish mountains should see the return of some snow at least by opening week of February, where it's been very snow barren. 

I think some on here enjoy fabricating something different to the reality!! The models seem indecisive to me but when are they not...who knows what today will bring. :wink: 

 

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16 hours ago, bluearmy said:

Latest day 5 FAX is interesting as it has a disruptive look about it and certainly builds the ridge ahead more than today's runs have

It is not taken from the ukmo run

as far as mondays front bringing anything wintry is concerned, thicknesses look much too high, even on that more interesting FAX 

 

THE COLD BLOCK CONTINUES TO HOLD ON BUT FOR HOW MUCH LONGER?                            ***Please see my 0830 Thur. Jan. 26th update at the end of this message***

BA - I was preparing this post and just noted your comments and I had also noticed the subtle changes on the MetO 18z fax charts compared to their UKMO 12z model output. The next 5 days may be very interesting. 

Firstly, the strength of the Euro cold block. The cold has steadily deepened during the last 48 hours and it has become much more extensive again. The live charts update every few minutes. I have frozen the third chart at 2350. The last two charts show the max temps for Monday and Tuesday. There's a progressively wider area of France with below zero max temps.

Please note that all the times shown on the Meteoceil charts are 1 hour ahead of GMT  

        NW Europe temps "live"                                        All Europe temp live                             All Europe temps at 2350                         NW Europe Max Temps Tue 24th                   NW Europe Max Temps Wed 25th

temp.png        temp_eur2.png      temp_eur2-23.png          tx.png         tx12.png

The HP has only moved very slightly eastwards - from Germany into eastern Euriope during thre last 24 hours, far less than forecast 24 hours ago and less than the earlier model output suggested (see my posts on page 312 and 313 on the old winter model thread). The the separate cell over south-east Finland last night has merged with the main HP. overall the HP block looks remarkably steady. The central pressure is still slowly rising. I also provide a link to the archive charts to view the changes over the last 24 hours. Just click on "animation on 24" above the chart and it take 10 seconds to load up. All four charts have 1 millibar pressure gradients.

        Live Europe Pressure Chart                                Europe Pressure 0050 Thursday                                        Live France and UK Chart                                              France and UK Pressure at 2348     

  pression2_eur2.png                    pression2_eur2-00.png                         pression2.png                               pression2-23.png

  

The link to the Animated Chart:       http://www.meteociel.fr/observations-meteo/pression.php?region=eur2

Met Office 18z Fax Charts vs UKMO Model 12z:

           MetO Current 1800 Wed 25th                 MetO  T+24   1800 Thur 26th                    MetO     T+36 0000 Fri 27th                   MetO     T+48 1200 Fri 27th                      MetO  T+60 0000 Sat 28th                        

  20170125.1900.PPVA89.png  20170125.2156.PPVE89.png 20170125.1658.PPVG89.png  20170125.1658.PPVI89.png    20170125.1804.PPVJ89.png

             MetO  T+72 1200 Sat 28th                     MetO  T+84 0000 Sun 29th                        MetO  T+96 1200 Sun 29th                      MetO  T+120 0000 Mon 30th          

20170125.1804.PPVK89.png     20170125.0556.PPVL89.png    20170125.2221.PPVM89.png    20170125.2226.PPVO89.png                                                                                  

                                                     

                                UKMO T+72 1300 Sat 28th                                    UKMO T+96 1300 Sun 29th                                         UKMO T+120 1300 Mon 30th  

                    UW72-21.GIF                     UW96-21.GIF?25-18                         UW120-21.GIF?25-18        

 

The fax charts only go up to T+120 and the UKMO model only starts at T+72. So, I have only included the three UKMO charts in the overlapping period. The Fax charts are only updated a few hours after the 12z UKMO but they are less progressive and the fronts look like they will stall or disrupt against the HP to east. Even after the initial break through, it looks like the Euro HP will be fighting back. Even though we are looking at D1 to D5, it looks like this will be a forecasters nightmare - no wonder the models are struggling with the very short term yet to be resolved! This will be a fascinating period to watch and I expect some very sudden changes in the next few runs.

Finally, the live satellite imagery. This shows the increasing south-south-easterly drawing in the very cold air from France (as at 0030 on Thursday).

         NW Europe Satellite "live"                                NW Europe Satellite Thur 26th 0030                                       NW Europe "live" surface winds                      NW Europe surface winds Thur 26th 1248             

anim_ir.gif                   satir-00-30.gif                                vent.png                   vent-12.png                   

 Link to Archive Satellite Imagery:             http://www.meteociel.fr/observations-meteo/satellite.php?region=eur2    (click on "archive", set date and time and click"OK")

EDIT (1230 Thur. Jan 26th):  I have just added the surface wind charts above. This demonstrates that, even with the south-south-easterly to southerly airstream, the surface winds are south-easterlies over the Channel and southern England and are east-south-easterlies of most of north-west France. For any signs of the milder air encroaching, watch out for a slight veering to due south or south-south-west along with temperature rises over western France, particularly the Brest Peninsular, as well as Cornwall. At the time of writing, the Atlantic fronts are still being held at bay - as can be seen with the line of frontal cloud in the live satellite imagery making hardly any eastward progress between 0030 and 1230.  Some milder air is encroaching into western France. Further north and east, this should not be confused with the natural daytime max temps. There is also an upper level cold pool moving up from France which should be over the south-east by Friday morning. This may produce a light snowfall just ahead of the milder air moving in later in the day. I'll do a separate post on this shortly but  for those interested please keep referring back here to the live charts. Plenty to keep an eye on today and tomorrow!

        Live Precipitation Radar

lastradar.gif

UPDATE (0830 Thur. Jan. 26th):

The HP has slipped a little further east overnight but has continued to intensify. The cold over France is again more widespread and slightly deeper this morning (more mid blues).

      All Europe Min Temps Wed 25th             All Europe Temps Thur 26th 0750                NW Europe Min Temps Wed 25th               NW Europe Temps Thur 26th 0748

tn_eur2.png    temp_eur2-07.png      tn.png       temp-07.png 

The UKMO 0z run is more similar to its 12z run yesterday and the 18z fax charts remain a little different - rather puzzling? As others have mentioned, the strengthening Jet Stream is "likely" to push the block further east during the next 5 days but it may still be a messy transition. If the milder air pushes through during Friday, it would only take a minor change (like a very minor backing of the flow) to bring back the cold from France, albeit temporarily. This is probably merely delaying the inevitable but fascinating to watch unfold. 

 

 

 

Edited by Guest
Updated 0830 Thur. Jan 26th
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Posted
  • Location: Broxbourne, Herts
  • Weather Preferences: Snow snow and snow
  • Location: Broxbourne, Herts

I spoke at work to a girl in Minnesota yesterday who had opted to work from home on account of hearing that heavy snow was due to arrive  at 3pm that afternoon.Speaking to her again today,it transpired that the snow didn't arrive until after midnight and wasn't of the intensity predicted. She said what had been predicted for her area had ended way way south.

It struck me that if the models that are no doubt prompting incorrect short-term forecasts are not getting a grip with what is happening in such a short term over ther, the knock on effect on the four and five day modelling for our neck on the woods has got no chance.

It did leave me wondering whether the poor forecast was prompted by what turned out to be a promising cold ECM run,while the butterfly wings of reality was what led to the more disappointing follow-ups.

Either way it does seem that there the generally such variability about for whatever reason that little local fluctuations upstream are  having more significant effects on subsequent mode runs than is usually the case.

The Atlantic ought to have broken through now going on what we were seeing last week.  As many have stated, potentially it won't for another week and ho knows another week after that. Then again it might!! I do take some comfort from the fact that,for all the strides in technology and our understanding of how weather patterns develop, there is much that remains as yet beyond the realms of scientific understanding.

I'm expecting a cracking UKMO 0z run when I wake up in the morning  :)   

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Posted
  • Location: Santry, Dublin, Ireland. 50 metres ASL.
  • Location: Santry, Dublin, Ireland. 50 metres ASL.
4 hours ago, Jason M said:

The term Bartlett was an internet forum invention and doesn't actually exist in meteorological text books. See below description lifted from the web...

Very well aware of its origins ad it's meaning. Thanks.

3 hours ago, Timmytour said:



I'm expecting a cracking UKMO 0z run when I wake up in the morning  :)   

I'm afraid you'll be sadly disappointed!

http://www.meteociel.fr/modeles/ukmo2.php

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