Winter Model Output Discussion - 06Z 09/02/13 onwards

[Cheshire Freeze]

Eh, this'll wind the mildies up

Pretty much bares out the dream progression of cold E'ly followed by sinking vortex and bitter cold from NE

[Mair Snaw]

I fail to see the need for 'nail in the coffin posts'. Anyone with a remote clue on how winter's have gone over the years will realise that settling snow is and will happen from this day right the way through to the very last few days of March and if the Uppers are suitable and high pressure in charge it will stick around. For my money thats another 4-5 weeks with the chance of snow events. Now I'm not sure what everyone constitutes as good winter weather, but the best part of snow is seeing it fall IMO. That can happen for another 4-5 weeks yet. So a chart tonight at t144, is NOT a final nail in the coffin.

Totally agree with the above post, how many ok febs have had cold snowy marchs follow them? last spring being a case for me, really warm end to feb after some snow at first, followed by a coolish start to march then hot end to march and less than a week later on the 4th April 30cm of snow in one afternoon. winters over posts and final nail in the coffin etc make me laugh, we were getting them in the middle of december and look what happend since.

[Tamara]

Mmn! - nice consistency continuing from this morning with the ECM. The period around t120 to t144 to negotiate but that would be a nice way to round off the winter with the synoptics that have been elusive all winter

Edited February 12, 2013 by Tamara Road

[mountain shadow]

and finally ive seen enough to convince me that winter has just about the final nail.

Guess your feeling a wee bit daft now?

Never try and call a run until its fully out. Great consistency from the ECM.

[Katiewombat]

Must seem confusing at times.

Basically the E,ly train does arrive on the ECM and to be honest even at +144 this appeared very likely. You will often find members have different interpretations of the model output and an understanding of how the run is progressing.

The most pleasing aspect of the ECM run is something we haven't seen all winter and that is a negative NAO developing.

Thank you. I think the only answer is to spend the spring and summer learning to read the models, from the more sensible around.

Does this mean all those who chucked rattles out of prams at the gfs have collected them again.

Kx

[Mucka]

I'm a bit suspicious of the later ECM charts and really would prefer not to have to rely on an FI signal for undercut though it is a positive that it is there.

Hopefully we can go back to more energy being sent SE in the mid term as that would give us a much quicker and more likely to verify solution.

[Cheshire Freeze]

Nothing like going out on a (Greenland) high!

[rory o gorman]

Eh, this'll wind the mildies up

Pretty much bares out the dream progression of cold E'ly followed by sinking vortex and bitter cold from NE

Yes i agree with height rises in the mid/long term ,but personally im not convinced of the PV dropping down .we may end up with a modified SE flow.

[Cheshire Freeze]

Yes i agree with height rises in the mid/long term ,but personally im not convinced of the PV dropping down .we may end up with a modified SE flow.

If we get the GH, the natural order of things would be low heights dropping into Scandi. In this instance they're tied into a sizeable chunk of vortex!

Remember potential trough-high-trough analogy.

Edited February 12, 2013 by CreweCold

[shaky]

Ecm is beautifull!!theres no south westerly winds at all from now till 240 hours!!its shows cold frost weather from saturday all the way till about 168 hours annd then BANG another siberian high forms causing 850hpa temps of - 10 to flood into the uk!!things are looking very wintry fir the rest of february!!

[EML Network]

Yet another day where both models decide to move everything backward, the ECM easterly's post 168 never come to fruition, if we we're seeing it at 128 then I might take notice of it, none of the models have had a clue all winter long though, so at this juncture just about every option available is on the table.

The only thing I will say is that both the GFS and the ECM are determined to get the UK under the cold air eventually, but it's consistently being moved back....at this rate we might just get what we want by Dec.

Not buying into anything I see beyond 5 days right now

[chris55]

Well ECM, once again, offers us loads of colder prospects as we head into the second half of Feb, GEFS has a few stragglers showing a similar evolution. Although at range nothing can be trusted 100%, I'd say ECM is the model to watch over the coming days, with the likes of GFS and to an extent the UKMO following on behind.

Overall, decent winter model watching tonight. Potential is there, and a whole lot more interesting than a Barlette.

Edited February 12, 2013 by chris55

[goosey007]

Eh, this'll wind the mildies up

Pretty much bares out the dream progression of cold E'ly followed by sinking vortex and bitter cold from NE

nice eye candy indeed ...i hope we see this trend over the next few days.....as this winter more than any has taught anything more than +96/+120 is superduper FI

[MR EXTREMES]

we shall see in 240 hrs and by far not a mild run but i sit firmly on the fence the last time i was convinced it went very wrong and that was ecm only to be watered down so much it rejected the full on block.

so its not a case of it will its a case of maybe this evolution will happen but im not convinced and could well be the ukmo that has the more convincing run and outlooks dry cool days cold nights but dry.

[The Northern Ramper]

The ECM 240 is great and the trend for heights to our nw are evident again.

My main concern though is that 24hrs on and we are still at 240.

[rory o gorman]

If we get the GH, the natural order of things would be low heights dropping into Scandi. In this instance they're tied into a sizeable chunk of vortex!

Agreed but still not convinced of fully cut off heights over greenland . A possible solution would be a scandi high with heights sinking over or just to our east with a flow from a weakened cold pool over europe. hoping for the cut off though, as ireland has had sweet f all from this winter.

[london-snow]

http://www.meteociel...0.GIF?12-0##THe sausage high in full force-

In the league of Highs for the UK which are the best???

1) Sausage ( in the right place )

2) Iceland

3) Greenland

4) Scandi

5) Arctic

6) Siberian.

7) Atlantic ( especially if held back west like Dec 81)

S

London snow dont you owe me a pint for the 4 days of easterly winds?

LOL its all well and good having it but 99.9% of the cold lovers are only after one thing you know that..

Besides you have had one free beer from me already off the pile competition.

Edited February 12, 2013 by london-snow

[chris55]

LOL its all well and good having it but 99.9% of the cold lovers are only after one thing you know that..

Besides you have had one free beer from me already off the pile competition.

I can't work out whether that is Sausage or a Greenland high, lol.

[Gibby]

Good evening. Here is the Shrove Tuesday version of the 12z output from GFS, UKMO and ECM for today Tuesday February 12th 2013.

All models show a change in the weather from tomorrow. The current cold and static air over the UK will be attacked by an active set of fronts moving in from the West tomorrow bringing a spell of rain with a good deal of snow for Northern and Central areas albeit temporary. The fronts clear away East over Thursday wilth a NW flow bringing fine and milder air across the UK with a few showers in the North. On Friday the weather will be largely fine and mild with some pleasant sunshine especially in the SE where temperatures will approach double figures temperatures by day. Over the weekend rather more cloud will move NE over the UK with a little rain but no great amounts with most of it restricted to the far NW by Sunday in the continuing temperatures above what we've been used to of late.

GFS then shows next week with the UK under High pressure centred close to Southern and Eastern Britain with a lot of dry and fine weather with sunny spells by day and frosty nights. Temperatures would fall somewhat to near average or just below average levels by day as the week progresses. Late in the run High pressure migrates to Scandinavia with a resulting Easterly flow along with increasing instability bringing the risk of wintry showers in the East and South as things turn rather chilly again.

The GFS Ensembles show a milder spell is on the way. After the innitial rise in uppers on Thursday which last several days things fall back somewhat but only temporarily in this run as renewed milder air develops again later. The operational run is a cold outlier in its end of run cold snap while precipitation levels is quite small overall with some longish dry spells from most members.

The Jet Stream shows the SE flow over the UK in association with the approaching warm front tomorrow is the trigger for a weakening of the flow around the British Isles in the reliable output from the weekend onwards. The main thrust of the flow is shown to travel East at around 40 deg No towards Spain in a week or so.

UKMO for the start of next week shows High pressure over Europe slipping South. A deep Low in the Atlantic South of Iceland would be swinging troughs into the UK from the West with time bringing rain at times. Temperatures would be close to normal.

ECM for early next week shows a slack SSE flow over the UK with Low pressure out to the West pushing a frontal trough slowly towards Western Britain early in the week. The High pressure block to the East intensifies and moves North later setting up something of an Easterly flow with attendant colder conditions again later in the run and the risk of a few wintry showers in the rather cold conditions again by then.

In Summary High pressure continues to show dominance beyond this week. As in this morning's output the positioning of the High is paramount on conditions at the surface but the overall trend is for it to setup either to the Northwest, North or Northeast of the UK which will gradually mean that temperatures fall back somewhat at least for a time with much drier weather for all areas than has been experienced over the UK for some considerable time.

[weather eater]

My word but I admire the optimism on here, It’s like that song Tub thumping,†I get knocked down but I get up again aint nothing gonna keep me downâ€. We all know the Overall ECM verification stats but I cannot remember a decent easterly modelled by the ECM at 144hrs plus actually happening, I will happily take a bet with anyone that we will not see a decent easterly from the current modelling, it’s a win win bet for me even if I lose.

[goosey007]

Anybody notice how the deep cold 850s launch from the arctic towards the whole of northern europe on ecm between +216 and + 240 shame its deep FI ......hopefull though

[Matty M]

Overall you could call the broad pattern for the next few weeks.

Feb 22/25, High Pressure dominating. Easterly of sorts, probably very settled and progressively cold.

Feb 25-March 3rd: Increasing Geopotential Height anomaly over Greenland/ PV shift to Scandy/ Russian Arctic. Likely UK/IRE in Northerly/ Northeasterly.

[Severe Siberian icy blast]

Agreed but still not convinced of fully cut off heights over greenland . A possible solution would be a scandi high with heights sinking over or just to our east with a flow from a weakened cold pool over europe. hoping for the cut off though, as ireland has had sweet f all from this winter.

I can completely understand you been sceptable , but for me a Greenland high pressure is looking more and more likely, with the vortex moving away from Canada , and a strong vortex over Siberia , it really does encourage heights to build over Greenland , although I'm not saying a high wont be over scandi , but it looks unlikely with a vortex above it , but if it does then like you said it would likely sink , as the vortex pulls into Europe , but then I would expect heights to build over Greenland once the sinking highs gone , it's really just putting off the inevitable in my opinion.

That's not me with cold tinted glasses on , that's how I see the Synoptics going over this next 14days . Very interesting times ahead .

Glacier point back in January talked about this very situation , obviously it didn't happen at the time as the Canadian vortex really persisted in its home , but he did elude by saying that once you can get the Siberian vortex acting as the dominante sector then as we see greeny hight rises , it coincides with Europes/uk severest winter weather.

If this takes place as been hinted at by the ECM inparticular , then I'm in little doupt of the outcome .

Lets see how things plan out

[winterof79]

My word but I admire the optimism on here, It’s like that song Tub thumping,†I get knocked down but I get up again aint nothing gonna keep me downâ€. We all know the Overall ECM verification stats but I cannot remember a decent easterly modelled by the ECM at 144hrs plus actually happening, I will happily take a bet with anyone that we will not see a decent easterly from the current modelling, it’s a win win bet for me even if I lose.

What is your take on the METO further and MRF in comparrison to the output.?Presumably no easterly influence.

[Zenarcher]

Lets take a look at the three main models and their differences,

72 hours side by side image

The GFS and ECM have the low slightly further North and deeper than the UKMO but the cold air the low moves into on the GFS is slightly more further East compared to the ECM and UKMO. Over at the UK they seem uncertain on how much high pressure will move in the ECM seems the most keen pushing 1020mb up to Southern Scotland but the UKMO and GFS only bring 1020mb to Northern England.

96 hours comparison

Each model handles the low differently with each of them not agreeing 100% but the GFS is half like the UKMO and ECM. Over to the West of the Atlantic we see the UKMO and ECM build up high pressure the GFS also does this but has it more flatter.

120 hours comparison

Despite the UKMO and ECM handling a few things different earlier on they end up looking similar here and not to the GFS they both have the high pressure in the West Atlantic help things but the GFS that didn't build it up in the same way at 96 hours continues to look more flat at 120 hours.

144 hours

ECM and UKMO once again looking similar here and leave the GFS on it's own with it looking more flatter out of the three.

edit - Just want to add at 144 hours the UKMO and ECM have good heights over the north of the UK.

Edited February 12, 2013 by weathermaster