Winter Model Discussion 18Z 19/1/13 onwards.

[Carlrg]

http://www.meteociel...&mode=0&carte=0

The fat bird Shannon Entropy has yet to pick up the Karaoke mic.

http://www.meteociel...=144&carte=1021

But is stood at the bar, waiting to pounce with Pina Colada in hand.

http://www.meteociel...&ech=192&mode=0

And at the very last minute Nigel, Shannon's ex boyfriend has dragged her from the pub kicking and screaming.

http://www.meteociel...h=72&carte=1594

Shannon escapes the clutches of her ex lover, runs back into the pub and snatches the Karaoke mic out of the hands of Tracy and sings a lung busting rendition of it's raining men by the weathergirls.

Edited January 20, 2013 by Carlrg

[ItIsGee]

http://www.meteociel...&mode=2&carte=0

hi all

been watching these models for weeks now and i think i may have an idea how to read!!

in the meantime/..the above link, am i missing something? all local frecast point to snizzle but this thing of beauty is teling otherwise?

am i reading into this completely wrong?

Edited January 20, 2013 by crashlanding

[bradymk]

UKMO and GFS 12z still going for a breakdown end of the week into weekend. Another 5 days of very cold weather before that though with the potential still for it to extend. The breakdown looks to be to a less cold period rather than "mild" also.

Edited January 20, 2013 by bradythemole

[Panayiotis]

Nice WAA effect going on there wonder how far north it can go?

Edited January 20, 2013 by Panayiotis

[swfc]

well at 144 hrs the high still putting up a fight!!

[Panayiotis]

WIth these kind of uppers and dam you would think snow would be marginal and confined to the highlands, but no, dew points fairly low as the flow still coming of the cooler continent and there seems to be some hefty snow showers there even at low levels!

Edited January 20, 2013 by Panayiotis

[karyo]

well at 144 hrs the high still putting up a fight!!

Yes, which leads to a huge snow event over the UK on the GFS. The UKMO on the other hand has southwesterlies by that stage.

Karyo

[chris55]

Breakdown of sorts likely for the weekend, details uncertain. GFS throws up some potential snow as the Atlantic comes in,

MetOffice confident the Atlantic will break through, but the details are non existent at this stage, from Ian F in the South West thread. (this also refers to the week ahead regarding snowfall)

"It's a highly diffuse forecast re any semblance of local let alone regional detail through next 48-72hrs. Our broad note of caution is that given such low static stability, anything could happen, frankly. Our only area of high confidence is for a breakdown next weekend but clearly any detail on this isn't worth paper written on at current juncture."

[chris55]

12Z not really getting the Atlantic in to far at the weekend!

Sundays surface temps highlight this,

[J10]

Yes, which leads to a huge snow event over the UK on the GFS. The UKMO on the other hand has southwesterlies by that stage.

Karyo

Tonight's FAX should be interesting again, last night it was modified westwards, will it be again?

Or are they happy with the quick win of South Westerlies as portrayed on their model. Given the fact the UKMO has done so well lately, a lot of weight should be given to this tonight.

If the GFS battleground scenario was backed up tonight, I would give this more credence.

[chris55]

Monday morning, Atlantic hasn't made it, still chilly at the surface, high pressure more prominent to the east and north.

[Wayneywoo]

Indeed Dave but the fax shows increased influence from the HP extending down from arctic region. Its not Scandi HP or extension from south its an extension of HP from the arctic region thus its increased 'influence' is there on that Fax chart. Full blown HP to our north, NW or NE is down the line IMO....lets see what the models show come Wed or Thurs in their outlook...I suspect it won't be GFS FI. I am not thinking northerly at all either.

BFTP

I don't profess to be anywhere near as knowledgable as other guys on here but the way I see it, after constantly reading everyone's posts is I tend to agree with those that predict height rises to our N/NW.

Just by chance I have captured 22nd 1pm NH charts from the GFS and admittedly, one is the 06z and the other is the 12z and yes, I know we are supposed to compare run with run but these charts do show improvements at only T+60 now!

This was the prediction from the 06z last Friday 18th:

and the same point in time from the 12z a few moments ago:

I can clearly see an improvement in the Arctic HP trying to ridge towards our N/NW Greenland area and this is why I quote Fred above. I would tend to think that the SSW is giving the Arctic HP the upper hand and the more dominant player at the table at the moment.

Arctic HP - Needs 1 card to have a royal flush

Canadian Vortex - Needs 1 card to have a straight flush

Who is going to get the card they need to win??........

[Continental Climate]

I think what we should do is try to enjoy the next few days of cold and snow which lets face it has rescued this winter!! The breakdown will come but two questions remain how mild will it get and how long will it be until something cold starts to reappear again. I think it will get average temperature wise and the models may pick up on the next cold signal starting the 4th or 5th. I dont think it will come via greenie or iceland blocking more likely scandi again. For some reason blocking has refused to get going in greenie and thwe NAO remains reluctant to go negative. Those are my views

[Panayiotis]

12Z not really getting the Atlantic in to far at the weekend!

Sundays surface temps highlight this,

Yes I noticed that too, for my area the temperature doesn't get aboove 4C on Sunday, which is warmer than today but still cold, with warmer uppers arriving from the S/SW there would likely to be fog.

[weather eater]

Looking at the GFS 12z running out Ian F is absolutely right, the Atlantic looks the odds on favourite, But and it’s a big but (Careful Pete (RP)I said big but, not big Butt) there is a lot of evolving to do and maybe just maybe it will work out in our favour. For the first time in a while I hope the UKMO is off the mark.

Edited January 20, 2013 by weather eater

[SnowObsessor90]

Well GFS finally seems to be starting to 'get it' as far the SSW, a breakdown for next does week look likely now but whether it will to a prolonged period of Zonality is another question.

And now of course in typical fashion it reverts back to default in FI, it wasn't looking terrible before that though.

Edited January 20, 2013 by SnowObsessor90

[phil nw.]

Although the ens tell us otherwise there`s no great push from the Atlantic towards the weekend.

http://modeles.meteo...nh-0-144.png?12

http://www.meteociel...44-21.GIF?20-17

The blocking showing signs of fighting back-a better angle on the GFS with the tilt favouring more chances of undercutting.

I think we have been here before.

As Jack said it will be interesting if tonights fax`s issued around 22.30 will modify the raw UK outputs again.

A fascinating pattern this with the cold block constantly refusing to be overun by the Atlantic.

Edited January 20, 2013 by phil n.warks.

[Barry12]

A breakdown is not certain for next weekend, the GFS was showing a breakdown for Wednesday which never happened, I suspect things will keep getting pushed back.

Remains cold, midlands-North, with further quite widespread snow events.

Edited January 20, 2013 by Barry95

[Jonan92]

No more vortex in Canada

[bluearmy]

our friend gem is a bit less amplified mid atlantic at T72 compared with its 00z run

Edited January 20, 2013 by bluearmy

[chris55]

No more vortex in Canada

Yes the current split vortex we have (strat based) is, I think, forecast to move east and join with the other "spilt" segment over Siberia. And then reform into one displaced vortex (the reforming after the SSW) to the east.

Although downwelling and Trophespheric influences are beyond me. In laymens terms it would suggest a reformed PV to the east potentially allows height rises to the north west with a very cold flow from the N.E as we head through Feb.

The consequences of this is as the Canadian sector of the PV makes it's way to Siberia it will influence a more westerly type for us in the UK. But without this we wont see the potential re-establishment of colder conditions.

The only way around the less cold period is if the energy from the moving Canadian sector can go far enough south to keep the UK on the cold side of the jet.

Edited January 20, 2013 by chris55

[Catacol]

No more vortex in Canada

You are right - far worse now! We have a powered up Icelandic Low, an Azores High in situ and no easy route for the siberian vortex shard which has moved to Scandinavia at this point to drop over us. Thank goodness this is ridiculously FI... but the GFS this afternoon has done nothing but strengthen my fears over the latter part of January, the part where we were hoping for winter to begin to get its most solid grip. The vortex in the atlantic has died a death - not enough energy any longer to make it to Europe, but enough energy to push our block out of the way and leave us in a SW airflow. There it sits, fed by anomalously warm ocean temperatures for the time of year in the NW atlantic, and preventing any height rises of substance. This is December all over again.

All 3 of the big players have us in this position by 144, with GEM currently updating as I type. CPC anomaly charts have the same shape for the 8 - 14 day period. Anyone remember a post I put out a week or two ago about a sudden increase in solar activity again with 12 active spots at the start of the month? The sun has been moderately active this month with some quite impressive flares. A couple of years ago solar activity was the "in thing", much as Chio's excellent Strat work is now. MJO has reached phase 7 but is losing amplitude and suggesting a move to phase 8 before the month is out - and I say again that this takes us away from our mid atlantic high scenario for January. Further progress into phase 1 in February would leave us in a horrible anomaly profile

Today's GFS MJO plot has us in phase 1 by 3rd February, though admittedly this is the op run. Ensemble prediction still has February just moving into phase 8.

So in sum I am concerned and looking for some suggestion somewhere of the heights we need to the north to be built and sustained.

Edited January 20, 2013 by Catacol_Highlander

[EML Network]

ERM ??

920 MB LOW !! Don't think I have ever seen one of them on a GFS chart

[Frosty.]

A very active Gfs 12z run dominated by low pressure, even a 12 hour Northerly later in FI and some cold zonal mixed with mild in the later stages, the gfs is showing a huge depression at the end of the week trying to smash it's way through and blow the cold block apart and it does but it takes a bit of time and there is a very wet and windy spell which starts as snow, all in all, no quick fix return to cold from the 12z gfs, it's typically default zonal after the week ahead.

This chart is why I prefer easterlies to northerlies, northerlies usually topple rapidly whereas easterlies can sometimes sustain for a week or more.

[WhiteFox]

This chart is why I prefer easterlies to northerlies, northerlies usually topple rapidly whereas easterlies can sometimes sustain for a week or more.

I think that is true for both easterlies and northerlies frosty. A northerly can sustain so long as there is a strong block over greeland. Of course, they will topple without the block.

Easterlies, on the other hand, are more diffilcult to get in the first place, but they can also disappear fairly quickly without blocking in the right place.