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Posted
  • Location: Lancing
  • Weather Preferences: Sun, Snow and Storms
  • Location: Lancing
Posted (edited)
WWW.METEOCIEL.FR

Meteociel propose le modèle deterministe de ECMWF CEP en Open-Data avec une résolution de 0.25°

ECM has loaded to T360 on here now as well, nice setup in FI.

image.thumb.png.afc913deecc57c742151a1acb8e3f5b8.png

Edited by Mcconnor8
  • Like 3
  • Thanks 1
Posted
  • Location: West Yorkshire
  • Location: West Yorkshire
Posted

 Mike Poole Thanks for the update. In general it looks like a decent amount of success counting this down - we first saw it a few days ago at day 15, now some signs around day 10 / 11. The key for me is that we seem to be sticking to a similar valid time. Looking back to Monday, the start of the time of interest was around 8th-10th December, and we're still roughly in line with that.

I'm still looking at this with interest only for now, simply because day 10/11 is still a long way away. But it is a pretty consistent signal, so certainly merits keeping an eye on.

  • Like 8
Posted
  • Location: Wantage, Oxon
  • Weather Preferences: Hot, cold!
  • Location: Wantage, Oxon
Posted

 WYorksWeather Indeed, cautious optimism for now.

It’s worth remembering that it wasn’t that many days ago the output was looking dire across the piste.

We’ve come quite a way since that point, and the clear signal away from strat and trop coupling has been a big part of that.  

 

  • Like 8
Posted
  • Location: West Yorkshire
  • Location: West Yorkshire
Posted

Just as a bit of balance, and to maintain a little perspective, the ECM AI model illustrates how such a pattern with a mid-Atlantic ridge can go a bit awry from a cold perspective. This is the sort of detail that we will need a few more days on.

Here is the ECM AIFS at day 10 (left). It looks fairly promising. If anything, probably more amplified than the ECM OP (right).

image.thumb.png.9cdb47c3534ba6f5bce1ef371e5a8299.pngimage.thumb.png.1f3cd77f09872555eb9fa9898f16ae2b.png

Moving forward though, you can see the problem. At days 11 and 12, the block  fails to gain enough latitude, and then collapses.

image.thumb.png.ce142c4778c3ce1b845d8245f64aac32.pngimage.thumb.png.aa17b19b134e3b9017dd9ce15f406180.png

A second attempt starts at day 13, and joins a broad area of high pressure from the Azores through the UK to Scandinavia. Again though, it doesn't get far enough north, and the easterly is limited to central Europe.

image.thumb.png.93ccd7f3dfc31a1ae3d1139d32226f40.pngimage.thumb.png.ebf0d2093df725c826274a0f9c57e774.pngimage.thumb.png.16b07e8f75d102aae12d8a8636b9a968.png

Of course, we are a long way from resolving this kind of detail. It may well be that we do get a notable cold spell out of this. But this sort of chart reinforces that it is best not to get your hopes up too early based on charts that are still in FI.

  • Like 3
  • Thanks 1
Posted
  • Location: Norway
  • Location: Norway
Posted (edited)

after 5/6 dec a sudden shift to more blocking

love that EC -- E winds 

image.thumb.png.ce76b61c19b5b55528ea04e595d6b150.pngimage.thumb.png.3956bb2798c169800b5baddca48cd570.pngimage.thumb.png.e167c75075717e21f4d596ed2daf1046.png

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Edited by Dennis
  • Like 7
  • Thanks 1
Posted
  • Location: Nuneaton,Warks. 128m asl
  • Weather Preferences: Snow then clear and frosty.
  • Location: Nuneaton,Warks. 128m asl
Posted (edited)

 Mike Poole

I think the key here is the weakness of the vortex at the lower levels.

We are in the so called warmer mjo phases now and still we are not seeing a strongly positive ao/nao Atlantic pattern running riot.

Indeed the modest ridging we are seeing at times is indicative of the weaker tpv with those occasional incisions of colder air, against the grain if you like.

Reasons for coldies to be optimistic going forward especially if the mjo goes into the colder phases in December.

Later ens.outputs are encouraging.

Edited by phil nw.
  • Like 8
  • Insightful 1
Posted
  • Location: Heckmondwike, West Yorkshire
  • Location: Heckmondwike, West Yorkshire
Posted

A concerning trend today with regards to a big portion of the tpv setting up shop over Greenland around the time when we were getting those great run to run gfs ops yesterday. ECM AI has followed that trend today. My powder is dry for now. That period circa 11th to 13th December open to question still. On to tomorrow's output to see if we can see the pendulum swing back.

gfsnh-0-300.png

  • Thanks 1
Posted
  • Location: West Yorkshire
  • Location: West Yorkshire
Posted

 blizzard81 The change seems to start with this small low to the west at about day 8, which disrupts the attempt from the mid-Atlantic ridge to head up towards Greenland.

image.thumb.png.ae5860dfce6064114ad61fcf0917f9b5.png

Interesting that tonight's EC clusters didn't really back this scenario at all. As you say, an important set of runs tomorrow - first signs of some back-tracking here. 

  • Like 2
Posted
  • Location: Lancing
  • Weather Preferences: Sun, Snow and Storms
  • Location: Lancing
Posted

 blizzard81 17328364690776512244593164975807.thumb.png.3c48c08b29db9d3a4ee96b7aa704f4cf.png17328364792775204600702551704729.thumb.png.4d07854bee90749191e287d71cc3e529.png

GEFS also looking worse on the 18z than the 12z, but let's see what the 0z runs have to offer.

  • Thanks 1
Posted
  • Location: Pontypool, 132m ASL
  • Weather Preferences: Extremes
  • Location: Pontypool, 132m ASL
Posted

 Cambrian I’m not clever enough to completely comprehend your post but (to me) it is like Nigella interpreting the models - tempting and titillating. Love it. 👍

  • Like 2
Posted
  • Location: Cambridge
  • Location: Cambridge
Posted

We need to take cold attacks that harden step by step. It is not always possible to get a very hard system that appears suddenly. That's why I find every “possible” cold attack in diagram important 

Posted
  • Location: Norway
  • Location: Norway
Posted (edited)

the lemon is (sory to say) that MJO 4-5 are the worst for west europe when we talk of good blocking and wintercold 

again this isnt the end .....models struggling alot (well its weather)😋 but the day will come , keypoint a short later i think 9-11 dec

image.thumb.png.f2b4a615a401434739c7855e0070435b.pngimage.thumb.png.de10e26acb6e0b2ef2047ff486a98784.pngimage.thumb.png.5edf24f7613058474d9420f6365c4519.pngimage.thumb.png.8efd7c6dd327d7f5f412e8ee3db889dd.png

interesting to see that NAO block is at watch

image.thumb.png.078808333bfc9d3efc10b727c02482d0.png

 

Edited by Dennis
  • Like 1
  • Thanks 1
Posted
  • Location: Aberporth S W Wales
  • Location: Aberporth S W Wales
Posted

GFS still toying with a mid atlantic ridge but not quite got the elevation we need, difficult to tell with UKMO @168 but looks like it may be going in the right direction.

IMO and experiance this has to be the  way foreward in December.. a good MAR stretching to southern Greenland delivers cold to the UK 9/10 times, a Scandi high in December 1/10, often leaving the UK in no mans land with mild southerlies.  

  • Like 1
Posted
  • Location: Norway
  • Location: Norway
Posted (edited)

the key to..... thats the one million question ,  

or the BIG change we wait for 

Edited by Dennis
  • Like 5
Posted
  • Location: Heckmondwike, West Yorkshire
  • Location: Heckmondwike, West Yorkshire
Posted

All very wishy washy this morning with the models. That big chunk of vortex setting up shop over Greenland is a big concern.

  • Thanks 1
Posted
  • Location: Bournemouth
  • Weather Preferences: Dry mild or snow winter. Hot and humid summer.
  • Location: Bournemouth
Posted

 blizzard81 agreed. 

IMG_1764.png

  • Thanks 2
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