Jump to content
Cold?
Local
Radar
Snow?

Model output discussion - Jan 3rd onwards


Recommended Posts

Posted
  • Location: Sedgley 225metres above sea level
  • Weather Preferences: Summer heatwaves and electrical storms, and fidgid Arctic type winters
  • Location: Sedgley 225metres above sea level
    11 hours ago, Severe Siberian icy blast said:

    Morning guys and gals

    A quick one on this feature from the North, its making its way south coming into nornern England this afternoon moving south into Midlands this evening petering out all the while, 

    It's the one coming in behind this from the northeast that's getting my attention, and it's getting the attention of Carol too on BBC, very cagey but I'm old enough to spot a stand off approach which is down to uncertainty. 

    I think this may be a secondary low developing a wave across the front!? 

    I think it needs it watching for England and Wales tonight into tomorrow, 

    Wondering what was the thoughts on this from the seniors?!! 

    I've only just noticed this post, and it's very well spotted. There seems to be a feature that as been developing for a fair few hour now... And this one is slowly but surely slipping South... This could potentially bring some tricky conditions. 

    And again for the umpteenth time its snowing again here. Will this winter ever end..😅

    2021-01-07-19-39-26.png

    Edited by MATTWOLVES
    • Like 7
    Link to post
    Share on other sites
    Spotted a post you think may be an issue? Please help the team by reporting it.
    • Replies 2k
    • Created
    • Last Reply

    Top Posters In This Topic

    Top Posters In This Topic

    Popular Posts

    A seasonal absentee by-stander in all this - but a one-off offering from me. Its a pity that this post is getting taken apart in some quarters, because hypothetically it *could* promote some inte

    LOL, the only time I tend to interact with SL is to offer a different point of view, so I definitely would not report on his thoughts. Jeez he was still at school when I was monitoring the strat. 

    Been very busy but wasn’t a bad time to be away for a couple of days. Call a spade a spade - got next week wrong. Thought amplification would see off the impact of the displacing vortex given such wea

    Posted Images

    Posted
  • Location: West/East/Sussex Surrey border
  • Location: West/East/Sussex Surrey border
    13 minutes ago, northwestsnow said:

    Personally I think EC det has potential...

    But it is but one run....

    I hope we get an Easterly if only for the SE crew many of whom are yet to see snow.

    Its hardly been Siberia here but we have had a few falls...

    Yet to see snow in years lol

    • Like 2
    Link to post
    Share on other sites
    Posted
  • Location: Carryduff, County Down 420ft ASL
  • Location: Carryduff, County Down 420ft ASL
    20 minutes ago, IDO said:

    ecm apparently has better resolution in the strat so maybe we favour the ecm evolution. However, one will be right and one wrong, and then post that things may change so very uncertain?

    Saying that, I am not sure where the ecm op goes post-d10, lows spawning off the US as the jet powers through that region:

    d10 ecm US> ECN1-240.thumb.gif.c229750bb280aa7ce36466ef694ee736.gif

    That chart shows the lows slamming to a halt off the Eastern seaboard though as the jet buckles ahead of it.

    I think we're likely to see an a Greenland wedge attempt in the 8-10 day timeframe and it's whether that holds or gets blown away that will determine whether we get the cold from the North East after that into the last third of the month.

    Edited by mountain shadow
    • Like 1
    Link to post
    Share on other sites
    Posted
  • Location: Straiton 145m asl
  • Location: Straiton 145m asl
    39 minutes ago, BLAST FROM THE PAST said:

    ECM is a very interesting run.  At the end we have the trigger for an atomic explosion.....and getting there is reasonable on the ECM run.  Now let’s get consistency 

     

    BFTP

    Is your BFTE still on the horizon in your opinion 🤔

    • Like 1
    Link to post
    Share on other sites
    Posted
  • Location: Reigate Hill
  • Weather Preferences: Anything
  • Location: Reigate Hill
    3 minutes ago, mountain shadow said:

    That chart shows the lows slamming to a halt off the Eastern seaboard though as the jet buckles ahead of it.

    I think we're likely to see an a Greenland wedge attempt in the 8-10 day timeframe and it's whether that holds or gets blown away that will determine whether we get the cold from the North East after that into the last third of the month.

    Yes, but that is a d10 ecm op and open to question?

    The mean is less sure; d9-10: anim_wcr0.gif

    Link to post
    Share on other sites
    Posted
  • Location: Cambridge
  • Weather Preferences: Heavy snow & long hot summers
  • Location: Cambridge

    ECM mean looks awful for UK cold.

    Link to post
    Share on other sites
    Posted
  • Location: Sheffield
  • Weather Preferences: thunderstorms, heatwaves, extreme weather
  • Location: Sheffield
    7 minutes ago, MATTWOLVES said:

    I've only just noticed this post, and it's very well spotted. There seems to be a feature that as been developing for a fair few hour now... And this one is slowly but surely slipping South... This could potentially bring some tricky conditions. 

    2021-01-07-19-39-26.png

    Higher routes around here are expected to have a tricky morning commute. Hi res models show a potentially slow moving band of snow (perhaps a sleety mix at lower elevations if the precip isn't that intense) stalling across middle England before it gradually fizzles out.

    It will be interesting to see what the radar looks like in the early hours. Tomorrow looks very much like a nowcast sort of day!

    • Like 2
    Link to post
    Share on other sites
    Posted
  • Location: Cambridge, UK
  • Weather Preferences: Summer > Spring > Winter > Autumn :-)
  • Location: Cambridge, UK
    Just now, DCee said:

    ECM mean looks awful for UK cold.

    We’re unlikely to see any further cold here until the last third of January now.

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

    The ecm op is a clear statistical outlier by d6 and by d10 it does its usual and becomes useless for a representative of the suite:

    Pressure ecm mean London> graphe1_00_306.121536255_150.346206665___.thumb.gif.ea55ac1555d81b6ad0c6cbbe48521f77.gif

    Link to post
    Share on other sites
    Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth
    9 minutes ago, MATTWOLVES said:

    I've only just noticed this post, and it's very well spotted. There seems to be a feature that as been developing for a fair few hour now... And this one is slowly but surely slipping South... This could potentially bring some tricky conditions. 

    And again for the umpteenth time its snowing again here. Will this winter ever end..😅

    2021-01-07-19-39-26.png

    Don't go there 🤬😢 

    But the main problem in the next two weeks is the heights over Iberia. I've watched those over the years and they don't tend to be temporary features. Best chance of more wintry weather in such situations is, you've guessed it, up north - incursions from the N have just about enough opportunity to get that far south even with Iberian heights.

    • Like 2
    Link to post
    Share on other sites
    Posted
  • Location: Sedgley 225metres above sea level
  • Weather Preferences: Summer heatwaves and electrical storms, and fidgid Arctic type winters
  • Location: Sedgley 225metres above sea level
    2 minutes ago, DCee said:

    ECM mean looks awful for UK cold.

    Don't agree mate...the spread on those ens show the period around the 15th onwards is the time we could start to go cold again...A good 50% going colder by this stage,and I think Matt H maybe onto something with this timescale.

    graphe0_00_274_96___.png

    • Like 1
    Link to post
    Share on other sites
    Posted
  • Location: Wantage, Oxon
  • Weather Preferences: Hot, cold!
  • Location: Wantage, Oxon
    9 minutes ago, mb018538 said:

    We’re unlikely to see any further cold here until the last third of January now.

    Don’t think anything serious much earlier was ever on the cards though.  The SSW has happened but things take a while to sort themselves out. ECM mean and spread T240:

    85987069-315B-4870-AB6F-AF061F4D6A77.thumb.png.8848db6be56c42e5d877b3c8d34b0c7a.png5FCA3FA5-70E8-403A-9D75-9EA32AB5CBFF.thumb.png.8eb9c94cd48c6cb6633811e3920d84be.png

    Positives are vortex as far away as possible, signs of the arctic high as response to the SSW, uncertainty now reduced from practically everywhere to a few regions, upstream of UK (as always), upstream of the UK (from an easterly point of view!) - suggesting some mobility there.  Uncertainty reduction suggests the models are now getting to grips with the evolution post SSW.

    Will be good to try and unpack that a bit with the clusters.

    Edited by Mike Poole
    • Like 4
    Link to post
    Share on other sites
    Posted
  • Location: Manchester
  • Weather Preferences: Sunny and warm in the Summer, cold and snowy in the winter, simples!
  • Location: Manchester

    Taking a step back from the operational output, but keeping "Day 10" theme, the GEFS pressure chart mean for 240h is compelling when taken with todays move toward a more amplified pattern.

    gensnh-31-1-240.png

    Back that West and deepen the Scandi trough and Greenland high beckons with locked in cold.

    If we can keep the improvements coming then the next couple of days are going to show some potentially exciting Winter outcomes last 1/3 Jan

    Going off the scale optimistic we could see cold restored around mid Jan with cut off Iceland high soon reinforced by Atlantic ridge but that is better said in hushed tones.

    Eyes down for the pub run. Are we on the doubles or larger shandy?

    Edited by Mucka
    • Like 5
    Link to post
    Share on other sites
    Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

    ECMF_phase_51m_small.gif


    Thinking about the MJO signal again - there's a lot of spread here in both direction and timing of any propagation eastward.

    So, there's going to be a lot of spread in how AAM behaves in the next week, let alone the one after.

    A number of the runs will be keeping it low or drop it further still, lending sustenance to the high pressure over western Europe / Iberia.

    At the other extreme, a number will be increasing it in tandem with the MJO booking it through phases 4-5. In that scenario, support for the high pressure to our south wanes and it becomes more likely to shift somewhere between northward and westward.


    Tropical forcing uncertainty overlaid onto stratosphere-driven uncertainty! 😵

    • Like 6
    Link to post
    Share on other sites
    Posted
  • Location: 50/50 Greece/Germany
  • Weather Preferences: Cold winters, hot summers
  • Location: 50/50 Greece/Germany
    5 minutes ago, Mike Poole said:

    Don’t think anything serious much earlier was ever on the cards though.  The SSW has happened but things take a while to sort themselves out. ECM mean and spread T240:

    85987069-315B-4870-AB6F-AF061F4D6A77.thumb.png.8848db6be56c42e5d877b3c8d34b0c7a.png5FCA3FA5-70E8-403A-9D75-9EA32AB5CBFF.thumb.png.8eb9c94cd48c6cb6633811e3920d84be.png

    Positives are vortex as far away as possible, signs of the arctic high as response to the SSW, uncertainty now reduced from practically everywhere to a few regions, upstream of UK (as always), upstream of the UK (from an easterly point of view!) - suggesting some mobility there.

    Will be good to try and unpack that a bit with the clusters.

    We still don't know if the SSW is a minor or major warming. Only that a ssw happend doesn't mean a lot. Also FU Berlin looks a bit promesing on easterlies around 60°N/1000hpa (which quite high in the north to be honest). The thing I don't like is that low impact on 30hpa and lower (atm!)

    ecmwfzm_u_f216.png

    • Like 3
    Link to post
    Share on other sites
    Posted
  • Location: Banbury
  • Weather Preferences: Deep Deep Snow causing chaos
  • Location: Banbury
    15 minutes ago, mb018538 said:

    We’re unlikely to see any further cold here until the last third of January now.

    I think tomorrow will be cold and Saturday 

    • Like 2
    • Thanks 1
    Link to post
    Share on other sites
    Posted
  • Location: East Ham, London
  • Location: East Ham, London

    Evening all 🙂

    A pleasant but chill day in lowland East London and it seems some may get some snow tonight or tomorrow. I'm not optimistic for my corner of the world but I'd like a really severe frost to last most of the day for a change.

    It's not much to ask.

    The model output was awash with uncertainty last evening with all manner of different synoptic evolutions at T+240 and some marked differences as early as T+120. Will tonight bring clarity or confusion? My money (and it remains very nice money) is on the latter but we'll see.

    12Z GEM: the most bullish of the output last night towards a mild evolution. T+120 take sus to next Tuesday - a ridge of HP from Iberia to Ireland dominates the weather. A complex LP over Scandinavia has pulled down some frigid air while a new Atlantic LP is to the south of Greenland. SW'ly winds cover much of the British isles but a residual chill NW'ly affects extreme eastern areas. The initial push of milder air in the second half of the weekend is displaced by a colder push of NW'lies early next week with -4 to -8 uppers returning for eastern parts. From there, the evolution becomes more complex - HP remains over Iberia but the ridge disappears as Atlantic LP tries to move in but with no jet to push the systems forward and heights building from the north, the trough is forces south and east over the British Isles by T+180. Mild air has pushed across the British Isles but a frigid block holds sway over Scandinavia. From there, the LP eases to the east and we get a brief blast of very cold NE'ly winds before a lobe of HP moves down from Greenland through the British isles to Iberia. Heights are strong over Greenland with the jet well to the south and a ridge over the British Isles. by T+240 the coldest uppers have moved to the south and milder air is again trying to encroach from the west.

    image.thumb.png.49c632d0b2178b9eacbb37353790ced7.pngimage.thumb.png.4077bcc79b161a86887715c062826a67.pngimage.thumb.png.8382c323fcead8a30d4543701d2bc411.png

    12Z GFS OP - a sharp pull away from the mild evolution of yesterday from GEM. GFS OP was quite mild as well so let's see if it follows the trend. At T+120 marked differences to the GEM. A small LP sits over southern Britain with a more pronounced build of pressure north to Iceland and the next Atlantic LP far to the west.  After a brief milder spell, colder air is already coming down from the north with -8 uppers close to northern Scotland. From there, the HP ridge remains in charge through to T+180 with weak Atlantic features moving NE and a long-fetch SW'ly in charge. This pushes milder air into Scandinavia. From there, the evolution gets a little messy but essentially the HP remains to the south and LP to the north-west with Greenland heights developing but not influential. It remains mild over the British Isles by T+240 with the coldest air far to the north.

    image.thumb.png.6ea4a868b29ad6cf6508d12921580b4c.pngimage.thumb.png.d5d4a417e52aee5e22845a55b2ae073e.pngimage.thumb.png.895217cbc6cb1d97211c6d7022593fbf.png

    12Z Parallel - the OP keeps things mild but the Parallel was an intriguing offering yesterday. At T+120 there aren't huge differences with the OP. Colder air is pushing south across northern and eastern areas of the British Isles in the wake of the Scandinavian trough while milder air approaches from the west. By T+180 the weak Atlantic LP systems are close to the west but there's not much happening to the north and east and a strong ridge of HP is developing upstream in the Atlantic. Mild air covers the British Isles during this period. From there, weak areas of LP cross the British Isles and then ease SE and by T+240 one such elongated LP is off the north-east coast with a WNW'ly flow over the British isles and a cut -off Atlantic LP with further upstream ridging from Greenland. Milder air remains over southern and western parts while it's slightly cooler elsewhere. 

    image.thumb.png.f2573d9500b15a1a53e57a7191099648.pngimage.thumb.png.86fd1066e0780ae51caa84721cb9da9d.pngimage.thumb.png.080070ce2509152d0a5abf9a2d2f92b5.png

    12Z ECM - not quite sure about Parallel. It's almost as though it wants to go somewhere interesting but doesn't know how. Yes, it's all computer generated modelling and I shouldn't personalise it. Perhaps ECM can restore some sanity. It doesn't help with another different evolution at T+120. The British Isles is in a col with heights to north and south and LP system to the east and west. Milder air has pushed into most areas but it's still cold to the north. From there, the Atlantic LP goes nowhere slowly and heights try to build through the British Isles from the south. A light [email protected] to the east of the ridge has drawn -4 uppers back in to the UK while it remains mild to the west. It looks as though the Atlantic will take over but at T+240 the LP is moving across the British Isles while the HP eases WNW to join with heights over Greenland.  The possibility of a mid Atlantic block forming and leaving the British isles on the cold side is obvious.

    image.thumb.png.8aeecb761b8310ba30fb46472cb2370d.pngimage.thumb.png.ed9d99a17c6a7657236f396502abf899.pngimage.thumb.png.33dd17fd6b7a6df76d14f463689b634c.png

    Not for the first time, ECM tantalises and teases at day 10. Moving further on, the usual T+312 and T+384 charts from the GFS OP and Parallel runs respectively.

    image.thumb.png.0d374e945eebe2f3e7e873e563dec802.pngimage.thumb.png.5b0a20d617a143d5c4e6d3089177ebf5.png

    image.thumb.png.08490e24797c52714f3645a332ed1730.pngimage.thumb.png.9050d3910ba95161acef0620579c0fe6.png

    Both end mild though one has a powerful PV over Greenland and the other doesn't. 

    Looking elsewhere, 12Z Control ends stormy with a super-charged Atlantic. On the 10 HPA front, Control still has the second warming (which might explain why we are seeing a restored vortex in our part of the planet in far FI) which doesn't split the vortex. OP weakens the vortex more noticeably. and Parallel is much the same.

    Conclusion: GEM and ECM tantalise with some interest in their evolutions but GFS seems less interested tonight in promoting anything other than a mild Atlantic with HP to the south of the British Isles. I'm wondering if the second warming is being seen as a more traditional wave 1 warming which will shunt the PV back to Greenland/NE Canada where it can re-strengthen and fire up a strong zonal jet. It seems odd that a major SSW now seems to have so little impact later in the month but GFS has been playing this tune for a while. ECM at T+240 is a real tease while GEM at the same time isn't too bad. There are still significant synoptic differences early in the evolution so it's hard to take too many of the later charts too seriously. 

    • Like 1
    • Thanks 2
    Link to post
    Share on other sites
    Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth

    Woah, this is mighty close to a cut-off Icelandic High at T120, and on the mean chart. I wouldn't want to rule out a fusion between the two lows 

    Screenshot_20210107-200807.thumb.png.a2782e13b45a90d144b4430b1812a46b.png

     

    • Like 8
    Link to post
    Share on other sites
    Posted
  • Location: Redhill, Surrey
  • Weather Preferences: Southerly tracking LPs, heavy snow. Also 25c and calm
  • Location: Redhill, Surrey
    24 minutes ago, Penicuikblizzard said:

    Is your BFTE still on the horizon in your opinion 🤔

    Err what sort of nonsense is that?  Where’s your thoughts and outlook? 🤔nowhere.....your opinion going forward...I don’t expect one

    Edited by BLAST FROM THE PAST
    Link to post
    Share on other sites
    Posted
  • Location: Wantage, Oxon
  • Weather Preferences: Hot, cold!
  • Location: Wantage, Oxon
    Just now, Vikos said:

    We still don't know if the SSW is a minor or major warming. Only that a ssw happend doesn't mean a lot. Also FU Berlin looks a bit promesing on easterlies around 60°N/1000hpa (which quite high in the north to be honest). The thing I don't like is that low impact on 30hpa and lower (atm!)

    ecmwfzm_u_f216.png

    It is a major SSW by definition Vikos (zonal mean zonal wind reversed at 60N 10hPa).  It has already happened on 5th January.  But that by itself means nothing down here in the trop unless the repercussions are favourable, which as you suggest is still unknown.  

    • Like 1
    Link to post
    Share on other sites
    Posted
  • Location: Banbury
  • Weather Preferences: Deep Deep Snow causing chaos
  • Location: Banbury
    1 minute ago, MJB said:

    I think tomorrow will be cold and Saturday  😄

     

    • Thanks 1
    Link to post
    Share on other sites
    Posted
  • Location: Pershore
  • Location: Pershore

    Locking this one now, as it's a bit long. New thread here:

     

    • Like 1
    Link to post
    Share on other sites
    Message added by Paul,

    Please stick to discussing the model output in this thread. For more general chat , please use the winter/cold weather/snow chat, banter, moans and ramps thread

    For local cold/snow and weather related chat, please head over to the Regional Area.

    Guest
    This topic is now closed to further replies.
    ×
    ×
    • Create New...