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Model Output Discussion - 10th Jan Onwards


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Posted
  • Location: NR LOURDES SW FRANCE
  • Location: NR LOURDES SW FRANCE

    The GFS 06hrs run clearly highlights exactly whats wrong with the pattern, too flat upstream, we needed to see the Azores high further ridge north and delay low pressure heading east out of the USA.

     

    Then towards the ne, shortwaves and little areas of lower heights running nw around the high, you'll see that these cut off the blocks ability to ridge over the top of the trough near the UK.

     

    I'm afraid the priest has arrived and is about give the last rites for cold, the only shred of a possibility is that the upstream pattern is a bit more amplified than shown but overall we need a miracle  to see enough changes to deliver anything within the next ten days.

     

    Just another easterly implosion to add to the back catalogue!

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    Posted
  • Location: west yorkshire
  • Weather Preferences: extreme weather
  • Location: west yorkshire

    Regarding the output today. Yes it's a poor outlook. But if they have flipped in the last 3 days then to me they is a possibility they could flipp back to something colder. Keep the faith.

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    Posted
  • Location: st albans
  • Location: st albans

    Just a quick look back in time. Older EC run valid for Tuesday:

     

     

     

     

     

    FAX:

     

     

     

     

    This, for Thursday, shows the EC perhaps 10C out in 850hPa temperatures:

     

     

     

    of course that wasn't a dig specifically at ecm because all the main models were showing a similar solution at the time.  ukmo jumped ship over its next two runs, as did ecm and gfs by noon thursday. 

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    Posted
  • Location: Wellington, NZ, about 120m ASL.
  • Location: Wellington, NZ, about 120m ASL.

    of course that wasn't a dig specifically at ecm because all the main models were showing a similar solution at the time.  ukmo jumped ship over its next two runs, as did ecm and gfs by noon thursday. 

     

    Yes, just a good example I found from an old model thread, not a dig at the ECMWF specifically. 

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    Posted
  • Location: Cyprus and North east Swindon. 104 ASL
  • Location: Cyprus and North east Swindon. 104 ASL

    When looking at the strat charts , there is a pivot from east to west, to north to south - does this effect our weather?

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    Posted
  • Location: Redhill, Surrey
  • Weather Preferences: Southerly tracking LPs, heavy snow. Also 25c and calm
  • Location: Redhill, Surrey

    Well looks like the block gets pushed East/SE. I think we have a wet and cool week ahead but after signs of AZH and that sunken block linking. This will bring one very large block...over Europe. A calm, dry and mild last 3rd of Jan with poss NW still affected by fronts??

    BFTP

    Edited by BLAST FROM THE PAST
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    Posted
  • Location: hertfordshire
  • Location: hertfordshire

    Just a quick look back in time. Older EC run valid for Tuesday:

     

    Posted Image

     

    Posted Image

     

    FAX:

     

    Posted Image

     

     

    This, for Thursday, shows the EC perhaps 10C out in 850hPa temperatures:

     

    Posted Image

    Just goes to show how poor the modeling has been the last several days. This includes

    ens and anomaly charts etc. When you look at the models now you wonder where all the

    talk came from regarding a east/northeasterly.

    I am always suspicious of charts showing good synoptics for a easterly at t240 as you know

    the pattern will evolve and change but when it is showing strong support at t144-168 and you

    take into account  the verification figures of models such as the ECM and UKMO you a forgiven

    for thinking you are looking at something that is reasonably accurate. In reality they were not

    even close. Very poor.

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    Posted
  • Location: Broadmayne, West Dorset
  • Weather Preferences: Snowfall in particular but most aspects of weather, hate hot and humid.
  • Location: Broadmayne, West Dorset

    So there we have it Another ECM false alarm raise the hopes of us coldies only to dash them yet again.

     

    Much as I am one to say keep the faith I do think this particular episode is over, However I wouldn't write off the winter as whole just yet.

    With the predicted attacks on the polar vortex February may yet hold the key to givingsome of us some of the white stuff.

     

    I must admit I wouldn't mind a euro high to give the southwest a drier spell to end January I have recorded 14 inches of rain since mid December

    and Dorset really needs to dry out a bit.

     

    I'm surprised that the ECM with its improved scaling should have got the Easterly wrong again. as another poster has noted it has improved its upper air capabilities, however the last time I checked human beings live on the surface of the planet so although what happens up there can make our weather down here.

     

    The actual weather we experience happens down here and it is that that we need to be modelled and forecasted correctly.

     

    With the UK being such a tiny land mass in the global scale of things tiny differences in verified modelling will always make major differences to the weather we experience.  A fact that we have to live with.

     

    Never mind bring on February and March.

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    Posted
  • Location: Bude
  • Weather Preferences: Extreme weather...heavy snow and heat waves
  • Location: Bude

    You know the outlook is poor for cold weather when even frosty hasn't got anthing positive to say

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    Posted
  • Location: Freshwater Isle of Wight
  • Location: Freshwater Isle of Wight

    ECM and GFS both show a developing block to the NE from around T+96 . GFS still goes for trough disruption over the UK and continues this right up to 192. If the block develops as predicted by these models the trough disruption could easily be further east or further west. Lets first see if the block does indeed develop and take it from there.      

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    Posted
  • Location: Redhill, Surrey
  • Weather Preferences: Southerly tracking LPs, heavy snow. Also 25c and calm
  • Location: Redhill, Surrey

    This trough getting stuck over us next week is bad news, be prepared for more flood issues. Water levels are still high....not good.

    BFTP

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    Posted
  • Location: NR Worthing SE Coast
  • Location: NR Worthing SE Coast

    ECM and GFS both show a developing block to the NE from around T+96 . GFS still goes for trough disruption over the UK and continues this right up to 192. If the block develops as predicted by these models the trough disruption could easily be further east or further west. Lets first see if the block does indeed develop and take it from there.      

    yes and the 06gfs which we have been told is the most progressive  of the 4 gfs runs a day has the block further west again than either the ecm and ukmo do this morning

     

    so maybe this still is not done and dusted yet.

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    Posted
  • Location: Darton, Barnsley south yorkshire, 102 M ASL
  • Location: Darton, Barnsley south yorkshire, 102 M ASL

    This is the same for most models. Gfs seems to model our patch of the nortj atlantic pretty well within 96 hrs, especially in zonal conditions. Forget trying to model accurately beyond 140 hrs, upstream amplification springs to mind here.

    The ECM didn't raise a false alarm we did. Its not written for the South East corner of England but a global model The Easterly is still there just not in our little corner No where did I see much lower temps mention in paper or web forecast It was a 'possibility' but we still need a number of things to fall into place and they didn't. FI is there for a reason, we cant accurately forcast beyond T168 so lets go back to looking at T240 models and blame ECM when they let us down.

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    Posted
  • Location: st albans
  • Location: st albans

    the behaviour of the trough in the supposed 'reliable timeframe' is indeed uncertain, as is any movement of the block. what has changed this morning is the flatter upstream around day 7 which prevents the atlantic ridge from getting north and linking up.  this flatter pattern bulldozes the block further east.  the behaviour of the block in the early/mid range may well present some surprise interest as the trough disrupts but its unlikely to be particularly notable. its what follows which has led to the 'game over' posts from the more experienced contributors this morning.

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    Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

     

    Now before someone screams northern blocking cross polar flow bitter cold etc etc it is

    not as simple as that because first these charts are just forecasts and need to verify and

    second by the time this propagates down into the the troposphere there could well be

    residule areas of vortices to our north over Greenland etc that would scupper any cold

    synoptics etc but at least our chances of something more akin to winter will of hopefully

    increased.

    very sensible caution there CC, it is a forecast and like any other needs careful and objective checking over the time scale.

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    Posted
  • Location: NR LOURDES SW FRANCE
  • Location: NR LOURDES SW FRANCE

    just to show how progressive the 00z ecm ens are, the AO and NAO go neg to pos a full 48 hours earlier than yesterdays 12z runs.

    BA do you think that's a bit suspect or simply they've caught up to the trend upstream and the reduced signal for blocking to be further north?

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    Posted
  • Location: Broadmayne, West Dorset
  • Weather Preferences: Snowfall in particular but most aspects of weather, hate hot and humid.
  • Location: Broadmayne, West Dorset

    Now before someone screams northern blocking cross polar flow bitter cold etc etc it is

    not as simple as that because first these charts are just forecasts and need to verify and

    second by the time this propagates down into the the troposphere there could well be

    residule areas of vortices to our north over Greenland etc that would scupper any cold

    synoptics etc but at least our chances of something more akin to winter will of hopefully

    increased.

     

    Excellent post CC. Winter is far from over but we need so many things to fall into place to get a really decent cold spell that caution always has to be the watchword.

     

    Never the less if the current vortex forecasts do verify then perhaps we might get a shot or two at something genuinely wintry instead of this endless autumn that we have been locked into for what seems like an eternity.

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    Posted
  • Location: Waltham Abbey, West Essex 144ft a.s.l.
  • Weather Preferences: snow, thunderstorms
  • Location: Waltham Abbey, West Essex 144ft a.s.l.

    BA do you think that's a bit suspect or simply they've caught up to the trend upstream and the reduced signal for blocking to be further north?

    Sounds a bit suspect to me Nick. i know everyone's feeling cheesed off but i do think we need to wait until the end of today before we completely  dismiss the easterly.Posted Image

    Edited by john mac
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    Posted
  • Location: NR LOURDES SW FRANCE
  • Location: NR LOURDES SW FRANCE

    I've now commenced Indiana Jones and the Search for a cold Miracle! Perhaps I'm still in denial over this recent non cold debacle! Just a few things concerning the upstream pattern. There are some quite marked differences between the handling of shortwaves over in the USA between the models.

     

    The ECM and GFS are pretty similar over the USA and the real divergence is between those and the UKMO as you can see here:

     

    So the ECM at T96hrs:

     

    post-1206-0-35670800-1389531159_thumb.gi

     

    Now the UKMO for the same time:

     

    post-1206-0-85480700-1389531188_thumb.gi

     

    This was the discussion by NCEP re the evolution before that timeframe:

     

    ...SECONDARY SYSTEM ARRIVING INTO THE GREAT LAKES BY 15/1200Z...FINAL PREFERENCE: 00Z ECMWFFORECAST CONFIDENCE: BELOW AVERAGEON THE WINGS OF THE INITIAL AMPLIFIED SHORTWAVE MARCHING THROUGHTHE TN VALLEY WILL BE ANOTHER SYSTEM EXPECTED TO REACH THE GREATLAKES BY EARLY WEDNESDAY. AS EXPECTED THIS FAR INTO THE SHORTRANGE PERIOD...MODEL DIFFERENCES ARE EVIDENT WITH THE 00Z UKMETBEING ONE OF THE SLOWER PIECES OF GUIDANCE OUT THERE. THE 00ZECMWF HAS SLOWED RELATIVE TO ITS PREVIOUS RUN WHILE ALSO NOTDEPICTING THE CLOSED LOW CENTER IT HAD EARLIER ADVERTISED. GIVENTHE IDEA OF FOLLOWING THE SLOWER SOLUTION FOR THIS LONGWAVETROF...WILL LEAN HEAVILY ON THE 00Z ECMWF HERE TO BE CONSISTENTWITH THE FEATURE DOWNSTREAM. CHOOSE NOT TO INCORPORATE ITSENSEMBLE MEAN AS EXPECT THE NEW MEAN TO SLOW TO MATCH CLOSER TOITS OWN DETERMINISTIC MODEL.What happens there will effect the troughing near the UK especially in terms of timing in relation to when these pieces of energy phase, as soon as they phase and depending on how they do so will effect  to a degree the movement of the troughing.Interestingly they haven't used the ECM ensemble mean because they think some of those ensembles are out of kilter with the upstream pattern.

     

    Another thing from this mornings extended forecast discussion:

     

     THE MODELS/ENSEMBLES SHOW ANAMPLIFIED CENTRAL PACIFIC RIDGE/POSSIBLE CLOSED HIGH...WHICHUSUALLY BLOCKS EAST FORWARD MOTION OF TROUGHS APPROACHING THE EASTCOAST.

     

    And also this:

     

    THE HIGH AMPLITUDERIDGE IN THE WEST WOULD FAVOR KEEPING AREAS OF LOWPRESSURE FURTHER WEST...LIKE THE MEAN SOLUTIONS.Now part of the problem across todays operationals is the flatness of the pattern especially in relation to the Azores high being unable to ridge sufficiently north to slow down the next upstream low, perhaps this is the new correct trend  which of course is certainly possible, if its not perhaps we may see some changes on tonights outputs.

     

    Even with some changes though I think it's  a leap too far to expect anything majorly wintry to jump out, I think this is more in relation to how the troughing disrupts near the UK which may still develop a little wintry  interest.

     

     

     

     

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