Model Output Discussion - 10th Jan Onwards

[MP-R]

http://www.wetterzentrale.de/pics/Recm1681.gifIf only the ECM was right, we 'd get an easterly in a week... (Uppers aren't much but hey!)

 

Had we been in a colder airmass for a few days leading up to that, that chart would be great for snow for the south at least, sadly not in the present scheme of things.

 

I'm glad to see that at least the ECM, although not showing anything amazing wintry, does show room for drier weather. Tomorrow looks good, then wet midweek before drier at the weekend. Right now, especially for us coldies, dry is as equally important as cold.

[Nick F]

Lol, it's a mug's game this forecasting malarky!

 

The models always seem to struggle with trough disruptions, too strong an upper flow going into trough and it doesn't disrupt, less energy going into the trough and it'll disrupt. 00z GFS op perhaps in the former camp, 00z ECM op in the latter.

 

Not many of the GEFS members offering an easterly, so will be interesting to see where the ECM deter lies with the EPS.

 

Perhaps no deep cold to tap into if we do get the easterly, though the surface may be cold given the continental origin of the air.

[johnholmes]

 

perhaps their is too much reliance on computer models these days,but they just can't handle blocking to the NE , it's still no better than 20 years ago all those millions spent on computers as well

 

 

beyond 24 perhaps 48 hours no human can have the slightest chance of predicting the weather so we have to rely on models to give indications on how weather beyond those times may develop

[Gibby]

Good morning everyone. A new week but will the weather this week look any different to recently. Well here is my take on the outputs of the NWP for the next 10-14 days issued at midnight on Monday January 13th 2014 and lifted from http://www.norton-radstockweather.co.uk/Model-Analysis(2859336).htm

 

All models show Low pressure in the Atlantic with an unstable SW flow over the UK. A trough will move West to East through Britain today enhancing showers as it goes heaviest in the South and West. A ridge of High pressure follows tomorrow with showers restricted to the far NW as a result. Later in the day a new depression and fronts approach Western Britain and sweep East tomorrow night and Wednesday with rain and strong winds for all, heavy at times. Through Wednesday more showery weather will spread across Britain though a frontal wave across the South could delay the clearance here. The rest of the week and weekend looks very unsettled with the UK covered in relatively Low pressure with various features enhancing showers or producing longer spells of rain at times and with some snow at times on Northern hills.

 

GFS then moves into it's second half this morning with chilly NW winds with further rain at times and snow on hills. Later in the week the weather dries up from the SW as a stronger ridge passes over with some frost at night before milder Atlantic winds return before the end of the run with fronts bringing rain, this time more especially over Northern Britain.

 

The GFS Ensembles generally back up the operational model very well though if anything it delays the slight improvement illustrated in Week 2 to the very end of the period. With very average uppers across the UK throughout it looks unlikely there will be much in the way of wintry weather with rain at times likely throughout.

 

UKMO closes it's run with next Sunday looking unsettled with Low pressure positioned over Iceland with an open trough structure South and SE over and around the UK. As a result while there will be some dry weather especially inland the risk of rain or heavy showers is high in temperatures close to or a little below average sufficiently so for some Northern hill snow in places at times.

 

GEM continues the unsettled weather throughout it's later stages this morning with disturbances running ESE or East across the UK with rain events followed by sunshine and showers in brisk winds continuing right out towards the end of next week. As with the other models despite feeling chilly in the wind at times temperatures will remain close to just a fraction below average with some snow events on the higher Northern hills at times.

 

NAVGEM closes it's run with a Low positioned in the Southern North Sea with a chilly NW flow producing sunshine and scattered wintry showers. Looking over the horizon beyond termination of the run there seems little to stop further westerly winds and fronts to continue the unsettled and breezy pattern.

 

ECM shows a much colder feel next week although not remarkably so. High pressure to the SW and over Eastern Europe are trying desperately hard to link next week with the UK in the meeting ground with Low pressure troughs amalgamating and weakening in situ over the UK. There would be some rain at times and possibly sleet or snow over the hills with an Easterly flow for a day or two before slack winds in rather cold air become present later next week.

 

The ECM 9 and 10 Day Mean Charts are back to it's UK trough scenario looking the bias between the members of it's ensemble group this morning with therefore the most likely prospect of a continuation of the unsettled and changeable pattern with rain at times with High pressure too far to the NE and SW.

 

http://www.wetterzentrale.de/pics/Reem2161.gif

http://www.wetterzentrale.de/pics/Reem2401.gif

 

The Jet Stream today looks like continuing to blow somewhat weaker than of late. Nevertheless it continues to influence the UK weather as it flows East over the Atlantic and then dips SE to the South of the UK and on over Southern Europe. This maintains a UK based trough for some considerable time bisected by High pressure over Eastern Europe and the Azores.

 

In Summary the weather remains in an unsettled vein this morning with all models posting a lot of Low pressure based charts for the UK. As a result we can all expect further rain and showers across the UK for the next 10-14 days with only small but subtle differences in conditions day to day. Temperatures will never be overly mild and it may feel a little chilly at times in fresh breezes and temperatures close to or a fraction below average. There is the chance of some snow at times over Northern hills and if this morning's ECM operational run is to be believed this may extend to Southern hills too for a time next week. Despite this though there seems little to suggest we will be entering a anticyclonic cold spell soon so unfortunately the flooding risk though lessened continues for parts of the UK through the period of this morning's output.

[Yarmy]

ECM keeping us in the game somehow for 2 runs now:

 

 

 

Surprised this thread isn't slightly busier. ECM had support from the JMA last night, so let's see how the 0z of that model goes (currently at T84 and not a million miles from the ECM T96). Hints that the PV is getting stretched across the pole, although a large lobe remains across Baffin/Greenland. 

[nick sussex]

So the chances of a faux easterly increase this morning with the ECM, I've named it that because it can't at present tap into that deep cold.

 

Upstream there are again marked differences between the models with the model diagnostic discussion enough to give you  a headache, the sum total is that the slower solutions are preferred which does give some support to the ECM.

 

NCEP are factoring in  the recent pattern over there where slower has been closer to the mark. That discussion is for upto Thursday, I need more coffee before I tackle the medium term one!

 

Some interesting news, the NAM which was criticized this morning for being too quick like the GFS has now jumped ship on its 06hrs run, its  similar to the ECM over the eastern USA. 

 

I should stress these are just the differences upto Thursday, theres also past that point where it again turns into a bit of a mess upstream so certainly don't assume that the ECM is correct and will verify for the more interesting part of its output.  Thats still unresolved this morning.

Edited January 13, 2014 by nick sussex

[mulzy]

0z ECM temperature ensembles has shown slight improvement in the day 8-12 range from last nights 12z suite - though confirms that the easterly suggested by the operational will have no potency.

 

http://www.knmi.nl/exp/pluim/vijftiendaagse/index.php

 

However, I do like the day 10 mean - screams potential to me.

 

Edited January 13, 2014 by mulzy

[Nick F]

So here we are again with differences between GFS and ECM with regards to the upper flow post t+168, ECM amplifies the flow upstream over the N Atlantic - which allows the trough over western Europe to disrupt into a cut off low with pressure/height rises to the north, GFS keeps the upper flow flat and thus no disruption. 

 

The ECM disruption brings the Scandi block back into the frame, which may help block further attempts at the Atlantic regaining a foothold. But the crucial period for potential disruption T+168 and after, so more runs needed to see if ECM has picked up on something. Certainly wouldn't throw the towel in just yet in defeat to the Atlantic, but it's becoming a rather long-drawn out affair this east vs west battle!

Edited January 13, 2014 by Nick F

[MR EXTREMES]

ecm at 192 now look at the jma same time frame from lastnight

 

the ecm is even slower than the jma bringing lows out of the states !!!

I told ya I threw the towel in

Edited January 13, 2014 by emotional rollercoaster

[Jason M]

The problem with the uppers is that any flow will be steered by the low pressure system to our SE rather than the high over Scandi / Russia. So, we have a poor upper temp profile, no embedded cold air and a warmer than usual north sea. On top of that the isobars track back to the Med. Looking through both GEFS and GEM ensemble suites they are trending ever more zonal and at earlier timescales. Quite a few go for turbo charged zonality and there are a fair number that look uncannily like the charts a week or so ago with the PV camped just to the NW of the UK.Lots of uncertainty IMHO about the pattern but it does look like either way there will be lots more rain and certainly nothing notably cold for the foreseeable future. There will be some nervous ski resorts in Europe this morning as if we end up with the 'weak easterly' its a set up that will pump even warmer air up from the south across the alps.

[snowking]

 

 

However, I do like the day 10 mean - screams potential to me.

 

 

 

Ohh no, not the 'P' word again!

 

You are certainly right though and if we take a look at the wind directions for The Netherlands:

 

 

Certainly a cluster of solutions following the deterministic run (the det. actually providing quite a good mean for those solutions) taking us back towards hints of an E/SE'ly flow. We of course though have to bear in mind recent events and whether the ECMWF just has a tendency to over-amplify post day 5. We have often commented in the past that the GFS throws out the same zonal solution over and over again post 192 and thats why occasionally it deals with a breakdown better than the other models - it's a case of a stopped clock is correct twice a day. It could be that we are now witnessing a similar weakness with the ECMWF in that up until now it has always seemed to deal with northern blocking and trough disruption better than the other suites because it has a tendency to over-amplify a pattern and therefore during previous cold spells that have indeed verified it comes out looking the best (it must be stressed that I have no statistical evidence to back this up - just an observation from the last two winters in particular - even during the colder spells of January and March last year heights were constantly over-estimated towards Greenland).

 

So certainly a significant minority clustering of Easterly solutions but as stressed last week it's best in situations like this to wait until a much closer timeframe before heightening any personal expectation.

 

SK

Edited January 13, 2014 by snowking

[shedhead]

So here we are again with differences between GFS and ECM with regards to the upper flow post t+168, ECM amplifies the flow upstream over the N Atlantic - which allow the trough over western Europe to disrupt into a cut off low with pressure/height rises to the north, GFS keeps the upper flow flat and thus no disruption. 

 

The ECM disruption brings the Scandi block back into the frame, which may help block further attempts at the Atlantic regaining a foothold. But the crucial period for potential disruption T+168 and after, so more runs needed to see if ECM has picked up on something. Certainly wouldn't throw the towel in just yet in defeat to the Atlantic, but it's becoming a rather long-drawn out affair this east vs west battle!

Agreed Nick, but let's face it it's rarely any different.

 

Looking at the T+168hr from GFS, it's not hard to see how with some fairly minor changes the latter part of it's high res run could have ended up looking far more ECM like...the trouble is the same could pretty much be said about the opposite. To my mind the most important thing is to get the block in place first, at which point modelling it's future evolution should become a bit easier and more consistent....perhaps with a few welcome surprises too.

 

Edited January 13, 2014 by shedhead

[MR EXTREMES]

ecm at 192 now look at the jma same time frame from lastnight

 

the ecm is even slower than the jma bringing lows out of the states !!!

I told ya I threw the towel in

and if you really do need to buy an arc now would be a good time if the gem is to be believed ....

and the jma jet profile is good to

London ens

show that it will never be to mild either.

Edited January 13, 2014 by emotional rollercoaster

[Blake]

I posted on my forum last night the possibility of this happening... any thoughts on it at all?

 

 

 

Low pressure (red circle) to the west to head north east with high pressure breaking off from the Altantic high (black circle) following behind and building again over Scandinavia with low pressure sinking south into Southern Europe. It would probably take a good 4-5 days from this to get into place so at best I would predict a chance of colder conditions around the 25th January onwards.

 

I'm no expert but is this something that could happen to bring us that easterly we're looking for?

 

[Purga]

However, I do like the day 10 mean - screams potential to me.

 

http://www.youtube.com/watch?hl=en-GB&gl=GB&v=Rp6-wG5LLqE

[Summer Sun]

Latest GFS 8 day temperature anomaly, lots of cold building for eastern and north eastern Europe now, for the UK its a mixed bag slightly below normal for the north and Ireland, but slightly above normal for the south, some western coasts and Wales

 

[snowmadchrisuk]

If the ECMWF does come off as shown , I wounder if it could end up turning into something much more prolonged long term, I note these run's are starting to show low pressure a lot further South and with the AH trying it's hardest to link up with Scandi , the P/V trying to back a lot further Westwards in FI as well as the strat stuff currently happening the possibility of some kind of undercut backing the high further North and West might not be as far fetched as it sounds...  

[R.P. McMurphy]

Lots of deep cold building into Russia and Scandianvia.

 

UK Remaining around 0C - 5C.

 

[TEITS]

Wouldn't mind a tenner for every time I'd heard or seen this said GP. Easterlies modelled post T+144hrs probably fail to materialise 9 times out of 10, so whilst it's encouraging to see ECM has not given up completely on the idea I think it's prudent to assume it won't happen at this stage.

Depends because their are many different types of E,ly and on todays ECM your 9 out of times comment isn't correct for whats being projected. If todays ECM was predicting -10C E,lys then I would agree with you.

 

Personally what the ECM is projecting is perfectly plausible but unfortunately the chances of a deep cold E,ly are extremely unlikely. For starters the core of the cold is to the NE of the HP and if we compare to the chart below you see the complete opposite.

 

http://www.wetterzentrale.de/archive/ra/1987/Rrea00119870109.gif

 

Finally if we skip between +168 to +240 the core of the HP is actually moving E rather than extending W. So from a point of view of looking for cold & snow im disappointed even with the ECM output.

 

 

 

Cannot help but be in awe of that Jan 87 chart. The perfect E,ly with part of the Polar Vortex sitting underneath the Arctic HP.

[bobbydog]

GFS leaning towards ECM at +120-

 

 

 

 

+144 to +168 will be the crucial time to watch.....

[R.P. McMurphy]

Latest GFS 8 day temperature anomaly, lots of cold building for eastern and north eastern Europe now, for the UK its a mixed bag slightly below normal for the north and Ireland, but slightly above normal for the south, some western coasts and Wales

 

 

Gav, just to point out thats not above normal for the south - it's 0.2 - 2C mate, while the rest of the UK remains below.

Edited January 13, 2014 by Glenn W

[bobbydog]

00z at t+144-

 

 

06z at t+144-

 

 

big differences with the block hanging on rather than being pushed out of the way

[Troubleatmill]

Depends because their are many different types of E,ly and on todays ECM your 9 out of times comment isn't correct for whats being projected. If todays ECM was predicting -10C E,lys then I would agree with you.

 

Personally what the ECM is projecting is perfectly plausible but unfortunately the chances of a deep cold E,ly are extremely unlikely. For starters the core of the cold is to the NE of the HP and if we compare to the chart below you see the complete opposite.

 

http://www.wetterzentrale.de/archive/ra/1987/Rrea00119870109.gif

 

Finally if we skip between +168 to +240 the core of the HP is actually moving E rather than extending W. So from a point of view of looking for cold & snow im disappointed even with the ECM output.

 

 

 

Cannot help but be in awe of that Jan 87 chart. The perfect E,ly with part of the Polar Vortex sitting underneath the Arctic HP.

 

great chart Dave,

 

Prety much the whole of Winter 86-87  looked more like a late April/May Chart, if only it were now! great winter 

Edited January 13, 2014 by Nicholas B

[Yarmy]

Gav, just to point out thats not above normal for the south - it's 0.2 - 2C mate, while the rest of the UK remains below.

 

0.2 to 2C above average for the South, no?

[Fozfoster]

Things look to be further west@144! is this better?