Jump to content
Cold?
Local
Radar
Snow?

Model output discussion - 7th January onwards


Recommended Posts

Posted
  • Location: Weymouth, Dorset
  • Location: Weymouth, Dorset
    3 minutes ago, Leo97t said:

    The golden rule of getting cold in the uk is a mild eastern states/Canada so this is particularly surprising 

    A very simplisitc and one dimensional viewpoint.

    Sometimes it can be the case regards a firing up of the Atlantic with the thermal differential, at other times other factors will override / negate its effect.

    • Like 5
    Link to post
    Share on other sites
    Spotted a post you think may be an issue? Please help the team by reporting it.
    • Replies 7k
    • Created
    • Last Reply

    Top Posters In This Topic

    Top Posters In This Topic

    Popular Posts

    So a rather long post ( Will also clip into the winter forecast thread ) However just an update on saturdays post, a large debate around models - & I took the day 6 UKMO & GFS charts to c

    I assume the overnight ECM has (temporarily at least) put an end to the glass half empty stuff from some posters yesterday. I'm sure the next variation in op run will bring them back out - but if you

    It's all good folks - we are about to get slammed ? Think March 2013 imprinted on the middle of winter - what's not to love ! The slider solutions are dialled in as the wave guide changes, N

    Posted Images

    Posted
  • Location: HILL OF TARA IRELAND
  • Weather Preferences: SNOW ICE
  • Location: HILL OF TARA IRELAND
    2 minutes ago, Steve Murr said:

    Now ive actually walked in the door & looked- The UKMO is fine in terms of sustaining cold, however isnt quite as good as the ECM-

    Also we are only talking a couple of hundred miles correction we cant expect perfection @144 all the time-

    GFS is poor again- it just cannot see whats happening- but the transitional 24-36 hour window still applies

    Next focal point is FV3 - looks very good @78!

    It looks stuck on 78 meteociel. 

    Link to post
    Share on other sites
    Posted
  • Location: st albans
  • Location: st albans
    3 minutes ago, January Snowstorm said:

    Over to the ECM to save the day.

    @nick sussex no shares in GFS Nick but weren't you saying about 2 weeks ago that the ECM was very poor this season?

    Well it didn’t cover itself in glory on yesterday’s two op runs by mishandling the Atlantic profile ....

    • Like 1
    Link to post
    Share on other sites
    Posted
  • Location: NR LOURDES SW FRANCE
  • Location: NR LOURDES SW FRANCE

    The GFS is much too quick with the shortwave which runs end from Texas .

    2 minutes ago, January Snowstorm said:

    For me across all models (awaiting ecm) there's no proper heights to our North. I know weaker heights can sometimes deliver but in general a proper cold spell needs either a strong Greenland or Scandinavian high. Even on the morning runs a proper analysis for me was that things could go wrong and it was marginal.

    Also we've been mentioning the 20th January for a while now as the starting point yet that date is in view now and it ain't great.

    Over to the ECM to save the day.

    @nick sussex no shares in GFS Nick but weren't you saying about 2 weeks ago that the ECM was very poor this season?

    Yes after day 7 but not before. I’m not lauding the ECM it has been dodgy this winter in the later timeframe so far but still beats the GFS within the day 6 timeframe . The early part is important because that helps develop a small wedge to the ne . So if the GFS is wrong at day 6 the rest of its output can go in the shredder . 

    • Like 3
    Link to post
    Share on other sites
    Posted
  • Location: HILL OF TARA IRELAND
  • Weather Preferences: SNOW ICE
  • Location: HILL OF TARA IRELAND

    If FV3 is replacing Gfs why do we get hung up on such bad consistency from Gfs

    • Like 4
    • Thanks 2
    Link to post
    Share on other sites
    Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.
    4 minutes ago, bluearmy said:

    I always find this an odd thing ..... gfs is a better model in the USA than the other models cos it’s a us model ..... and the euros are better over Europe .... is there actually any evidence? Surely it’s more a case of the model bias being exposed in different geographical locales ???

    In any case they're global models so any bias early is going to be magnified downstream tenfold later in the run, we aren't talking about the Euro 4 which is built to model one area.

    Link to post
    Share on other sites
    Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

    I think GFS tries for a feasible outcome if the MJO stays quiet, in which we have Canadian-Siberian vortex lobe exchanges taking place while west-Scandinavian blocking keeps us under a cold continental feed, but the usual bias (zonal flow too strong, not enough recurve of the jet under the block) led to it looking much less appealing than it could have done.

    If, instead, the MJO manages a bit of activity over the C. Pacific then a ridge to our NW becomes more probable.


    Odds are, we'll have a much better position in a week's time than GFS has us down for anyway, so I've little concern with it this evening. Same goes for D8+ of GEM though it's hardly a poor outcome with the new trough diving sharply into Europe on D10 and another easterly on the way; it's just that it would be preferable to keep our existing cold pool going.

    • Thanks 1
    Link to post
    Share on other sites

    Everything is looking too flimsy and marginal on all models at the moment to set up any much awaited hlb. Although I still expect an improvement, it's gonna have to happen soon before we are locked out again

    Edited by Leo97t
    • Like 1
    • Thanks 1
    Link to post
    Share on other sites

    I have today taken a look at the GEFS T850 06z model and the GEFS Precip Run 06z for the next few days. From what I can make out a fairly cold spell will hit from late Wed Evening and last into Friday AM. Late on Thursday and AM Friday, a band of fairly heavy precip will sweep in from the West. It looks to hit the UK around midnight. I would say that given the cold temps shown in the models this will fall as snow in most places. The above models show the precip in a heavy band top to bottom of the UK marching east. A warmer air mass will follow but especially if the band makes landfall at night, the chances of a decent snowfall look good before we get into the warmer air

     

     

    Link to post
    Share on other sites
    Posted
  • Location: Dundee - 140m ASL
  • Location: Dundee - 140m ASL
    12 minutes ago, FiftyShadesofSnow said:

    Gfs seems to model NE USA and Greenland much better than the Euros, due to locale...12z concerning if it's spotted the flatter pattern due to the Canadian lobe an stronger jet...it's flat.

    image.png

    Very misleading and completely wrong. The ECM consistently outperforms GFS when it comes to snowstorms and hurricanes around the east coast of the USA - the pros over there always slate the GFS! ECM is their go to model when big weather events are incoming.

    • Like 1
    Link to post
    Share on other sites
    Posted
  • Location: leicester
  • Location: leicester
    3 minutes ago, Steve Murr said:

    GFS 12z out to 108 are about 2c colder in the extreme SE due to the slider having a more tilt to it-

    The ENS will be fine ??

    Steve where do you think that snow line from the slidee would be on ukmo at 144 hours!!am thinking south wales west country maybe!!

    • Like 2
    Link to post
    Share on other sites
    Posted
  • Location: New Ash green 150M / 500 FT
  • Location: New Ash green 150M / 500 FT
    5 minutes ago, Sawel said:

    Very misleading and completely wrong. The ECM consistently outperforms GFS when it comes to snowstorms and hurricanes around the east coast of the USA - the pros over there always slate the GFS! ECM is their go to model when big weather events are incoming.

    Yes correct 

    Anyway having analized every output tonight - this is where I think we will end up around 144... ( in 6 days )

    4983AE06-5A2A-4BAB-B7E7-6E51AB77FF03.thumb.png.a6a2969bcf56d716cb179a996b59396b.png

    Edited by Steve Murr
    • Like 4
    Link to post
    Share on other sites
    Posted
  • Location: New Ash green 150M / 500 FT
  • Location: New Ash green 150M / 500 FT
    1 minute ago, shaky said:

    Steve where do you think that snow line from the slidee would be on ukmo at 144 hours!!am thinking south wales west country maybe!!

    Yeah SW midlands as well

    Link to post
    Share on other sites
    Posted
  • Location: sheffield
  • Weather Preferences: cold ,snow
  • Location: sheffield
    1 minute ago, shaky said:

    Steve where do you think that snow line from the slidee would be on ukmo at 144 hours!!am thinking south wales west country maybe!!

    Please don't do this!!!!!!

    • Like 5
    Link to post
    Share on other sites
    Posted
  • Location: London Waterloo 0m/ Leeds Bradford Airport 200m
  • Location: London Waterloo 0m/ Leeds Bradford Airport 200m

    I'm not seeing much to get excited about if you live in the south, cold zonality doesn't deliver here. If I was back up north 200m asl I'd be more enamored with the runs but at present it's pretty underwhelming 

    • Like 2
    Link to post
    Share on other sites
    Posted
  • Location: Reigate Hill
  • Weather Preferences: Anything
  • Location: Reigate Hill

    The GEFS at T138 are all over the place, and it is clear these sliders at this range are a lottery. Assuming ECM has it correctly modelled maybe presumptuous, though I expect it to be nearer than the GFS op:

    gens_panel_occ2.png

     

    Link to post
    Share on other sites
    Posted
  • Location: NR LOURDES SW FRANCE
  • Location: NR LOURDES SW FRANCE

    I"ve done a couple of paintjobs to explain the differences between the UKMO and GFS:

    So as you can see on the former the low southern tip Greenland and the small wedge of high pressure to the ne of it circled orange. The direction of energy is se , you're drop down point will be through or just to the west of the UK. Its also slower upstream and sharper and also slower with the low heading ne out of Texas, this feature then runs towards the east coast later developing a deeper feature.

    UN144-21.thumb.gif.34c8d8e61302dabc55624e54dd97f7cb.gif

    Now if you look at the GFS for same time day 6:

    You'll note its flatter with the low southern Greenland , little if any wedge to the ne and the direction of energy is more east se.

    gfsnh-0-144.thumb.png.ad25a3ab731a6749e8c88a6181398310.png

    Given the GFS bias which has been documented by the makers of it and often referred to in the NCEP discussions its a very unlikely solution.

     

    • Like 9
    Link to post
    Share on other sites
    Posted
  • Location: Wildwood, Stafford 104m asl
  • Weather Preferences: obviously snow!
  • Location: Wildwood, Stafford 104m asl

    GFS is absolute balls again, GEM and UKMO right idea, sliding the low, hopefully GFS will soon bin the mild fest Friday

    UW120-21.GIF?13-17gem-0-120.png?12gfs-0-114.png?12

    Link to post
    Share on other sites
    4 minutes ago, nwextremeweather said:

    I have today taken a look at the GEFS T850 06z model and the GEFS Precip Run 06z for the next few days. From what I can make out a fairly cold spell will hit from late Wed Evening and last into Friday AM. Late on Thursday and AM Friday, a band of fairly heavy precip will sweep in from the West. It looks to hit the UK around midnight. I would say that given the cold temps shown in the models this will fall as snow in most places. The above models show the precip in a heavy band top to bottom of the UK marching east. A warmer air mass will follow but especially if the band makes landfall at night, the chances of a decent snowfall look good before we get into the warmer air

     

     

    Then after that the GEFS T850 06z and the GEFS precip run 06z show the 21st Jan as the coldest day on the model run. However I cant see much precip around on the 21st. Most weather sources such as the Met Office are pointing to the 21st so that should be encouraging

    Link to post
    Share on other sites
    Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.
    Just now, IDO said:

    The GEFS at T138 are all over the place, and it is clear these sliders at this range are a lottery. Assuming ECM has it correctly modelled maybe presumptuous, though I expect it to be nearer than the GFS op:

    gens_panel_occ2.png

     

    There's only a couple of bad ones, while there are subtle differences, those differences don't mean there will be a poor outcome, it might not be quite as good as the 6z suite, but thats not to do with this suite, we were coming off a very high base.

    • Like 1
    Link to post
    Share on other sites
    9 minutes ago, shaky said:

    Steve where do you think that snow line from the slidee would be on ukmo at 144 hours!!am thinking south wales west country maybe!!

    I think much depends on whether the precip band hits at night or in the day. If night, most could wake up to snow before the warmer air and the rain take over

    Link to post
    Share on other sites
    Message added by Paul

    Please keep this thread solely to discussing the model output. The model banter thread is available for more loosely model related chat, ramps and moans.

    Guest
    This topic is now closed to further replies.
    • Cold waves hitting Europe continue to threaten growers, is there a link to climate change?

      Much of Europe, not just the UK, has experienced unseasonably cold weather since the Easter Weekend. A plunge of cold arctic air brought by northerly winds early last week brought several nights of frost and even snow across large swathes of Europe, followed by another wave of cold arctic air spreads across much of Europe this week. The frosts causing damage to new growth in vineyards and orchardsa0spurred on by a late March heatwave, the vineyards of France werea0particularly badly affected.

      Nick F
      Nick F
      Latest weather updates from Netweather 4

      High pressure rules, but still chilly out the sun & watch out for a few showers

      High pressure in charge for the rest of the week but the airmass will be chilly, so feeling nippy out of the sun. Not entirely dry either, with scattered showers around the next few days, especially in the west. Read the full update here

      Netweather forecasts
      Netweather forecasts
      Latest weather updates from Netweather

      You'll need your coat because it's still cold out of the sun

      More April snow for Monday morning with a widespread frost. If you have outdoor plans this week, the chill in the air remains especially once the sun goes down. Read the full update here

      Netweather forecasts
      Netweather forecasts
      Latest weather updates from Netweather
    • Recently Browsing   0 members

      No registered users viewing this page.

    ×
    ×
    • Create New...