Model Output Discussion - 8th - 14th January

[Jason M]

Ensembles are 'more easterly' tonight but some weird charts with quite a few 'mildish' easterlies.

There are a couple like the one below, high pressure over Scandi, high pressure over Iceland, high pressure over Greenland but for the Uk allow me to introduce the Bartlett 'Low'

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=384&code=20&mode=0&carte=

[Matty M]

A very uninspiring run of the model output today.

It is quite unfortunate.

But the key for the outlook is determined around T48/72 where ECM and particularly the UKM have forecast conditions around Greenland far better than the GFS in the last few days.

A disappointing trend has been for heights not to push far enough into Greenland and for the Arctic High not to take as much initiative as we had hoped.

It has unfortunately been a slippery slope we have seen changes being continued from the first warnings signs on the GFS last night where changes around Greenland were shown but some people on here got distracted by events la la land. Then the 0z and 6z and now 12z are backing this up.

The outlook beyond 7-10 days is still up in the are.

But there is growing liklihood for the PV to rebuild in its position just west of Greenland while we battle between high pressure to our south and the jet to our north.

It may actually turn quiet chilly at times for parts of southern Britain by day 5-7.

Unfortunately January is heading towards its midpoint and Britain and Ireland are yet to see a significant

cold incursion.

Edited January 10, 2012 by Matty M

[Paul]

I complain about this every year but I don't know what the solution is.

I wish the people posting would consider that hundreds if not thousands of people come here during the winter especially just to read what may be happening and then get 3 consecutive posts giving 3 viewpoints of the models in 3 word sentences but no backing up what they are saying with examples.

Maybe this forum needs an ignore feature which hides posts from unhelpful people or does that already exist?

Already is an ignore feature:

http://forum.netweather.tv/index.php?app=core&module=usercp&tab=core&area=ignoredusers

[Isolated Frost]

PV towards Baffin.. optimistic over the svalbard heights, but it is cross-model agreement , the aleutian ridge is definitely trying to get that cross-polar high.. and with that russia/balkans trough digging in , a lot is going good on the gfs/ecm.

[UV-RAY]

Yes those winters from the m/e come back to haunt us with cold air plunging thru Greece, Turkey and the North African countries. This is the problem when the PV refuses to yield and blocking tries to establish to the NE - of course it can't and the cold air goes South or SSW.

ECM rounds off with a toppler, but there could well be scope for more PM incursions after that.

Edit - very disappointing that forum management have to keep thinking up ludicrous alternatives to the alternatives to my phrase !

Maybe because there is nothing modern about such synoptics!

Back to the models, well despite some rather confusing posts I personally don't think the output isn't that bad for cold. Cold zonality next week, and then possible height rises to the NW thereon. I eagerly await further updates from GP and Chino, to ease all the negativity on here.

Edited January 10, 2012 by Seven of Nine

[weathe20]

Didnt GP mention NW and N for the cold not east anyway. When was the last time a very decent easterly happend?? Patience is required. Im still learning, but my word, I cannot stress enough some posts are like chalk and cheese!!

[Frosty.]

The Ecm 12z operational run is very similar to the 00z version with the anticyclone being very reluctant to leave the south of the uk until later next week, it does eventually lose some control by T+216 hours and there is a very short cold blast for the far northeast of the uk by day 10 but the whole pattern has been shunted much further east in the later timeframe so instead of a potential nationwide cold and unsettled blast as the 00z promised, we get the briefest of interruption to the settled pattern with more high pressure to push in from the west. The ecm is not really on the same page as the gfs at the moment.

[weathergeek]

As already mentioned, you can read through the posts following the latest run(s) and not have the feintest idea what synpotics are to be believed.

May as well give up and come back another day.

I feel totally the same - I'm a complete newbie who first found this forum in Oct and had to decifer all the techy stuff to get even a vague idea on forecasting.....but I have never been so confused as I am now! I've never seen such neg/pos posts all in one go in such a short space of time!

I feel my little fix I look for on here each day is completely incomprehensible!

PLEASE somebody explain!

Thanx

H.

[ukpaul]

As already mentioned, you can read through the posts following the latest run(s) and not have the feintest idea what synpotics are to be believed.

May as well give up and come back another day.

There is one simple reason and that is because there is no definite outcome beyond anything but a relatively short timeframe at the moment. You are going to get people commenting on changes after 120h which vary wildly and, whilst all are 'correct' in the sense that they are plausible, they will be mutually exclusive. Add to that how you get the occasional misreading or attempt to guess something that we will find out ten minutes later anyway, and it's best to focus on the next five days and what signals emerge during that time that are likely to have an effect later. Anything else is akin to reading tea-leaves.

Anyway, I'm quite happy with this evening's output (if we're going to take the mood temperature) but it'd be nice to get something cold to kill off these bugs that I'm picking up.

[Daniel Miller]

Didnt GP mention NW and N for the cold not east anyway. When was the last time a very decent easterly happend?? Patience is required. Im still learning, but my word, I cannot stress enough some posts are like chalk and cheese!!

If that's what he said then I'll take it! Seem to get better snow/cold from the NW, being in Wales

Out of interest, is there such a thing as a trend through a particular time of run e.g a set of 18z constantly showing the same thing but changing on the other runs?

[Roger J Smith]

I think we may see improvements or trends closer to current outlier GFS pert 13, in large part because the low developing in eastern North America may not be as fast to develop or move northeast after 72h. There is already a weakening trend in the Greenland PV and a stronger vortex near Baffin Island. It would not take much from the current starting point to throw the balance back towards blocking and Scandinavian high building. Watch for this trend to appear in the next 24-36h of model runs.

[Grimsby Snow Lover]

Why has my post been included in previous quote?!!x

When typing your post WG make sure you type beneath the 'post' word

Edited January 10, 2012 by Grimsby Snow Lover

[Frosty.]

I may be wrong here but I don't think the ecm 12z looks much like what the meto are expecting next week, the meto outlook seems to follow what the gfs has been showing with much more unsettled weather spreading southeast and only the far south hanging on to high pressure influence for longest.

[Matty M]

I don't mean to be undermining of anybody and i think GP is a top top contributor and a breath of fresh air

to weather forecasting. However i can't help but feel some people on here are living by his every whim. Unfortunately

GP is not a guru, i wish he was! So people should realise that he could be wrong in his thoughts.

The current outlook is not positive and this is the model discussion thread.

The models out to the medium term show no good signs towards cold for UK and Ireland. The PV is forecast to be as strong as ever around Greenland by day 7 by all models, with high pressure near to our southeast.

If this is a thread to discuss the models, i feel that it would be misleading to talk about cold prospects for the UK in relation to the models as the major models are all showing broad agreement to T144 for PV locked to Greenland and a poor set up for cold conditions for UK and Ireland barring some chilly, dry weather which may be fed from the continent for a short period.

I think the idea of people playing with trends from day 10+ in the hope of creating a cold slant to their discussion are only fooling themselves.

over Gre

[Frosty.]

I think the idea of people playing with trends from day 10+ in the hope of creating a cold slant to their discussion are only fooling themselves.

Have you considered the possibility that the Ecm 12z op run might be wrong? The Gfs has been showing a cold zonal outlook today.

[Matty M]

Have you considered the possibility that the Ecm 12z op run might be wrong? The Gfs has been showing a cold zonal outlook today.

Of course i have. And i have included the GFS in my thoughts. However there will be no decent cold spell resulting from cold zonality, and id be 95% sure of that.

Some watery sleety showers in a breeze with a cold slot for Scotland. But will never be much for south of the border with a cold zonal set up, barring some freak events.

[Beasterly]

I don't mean to be undermining of anybody and i think GP is a top top contributor and a breath of fresh air

to weather forecasting. However i can't help but feel some people on here are living by his every whim. Unfortunately

GP is not a guru, i wish he was! So people should realise that he could be wrong in his thoughts.

The current outlook is not positive and this is the model discussion thread.

The models out to the medium term show no good signs towards cold for UK and Ireland. The PV is forecast to be as strong as ever around Greenland by day 7 by all models, with high pressure near to our southeast.

If this is a thread to discuss the models, i feel that it would be misleading to talk about cold prospects for the UK in relation to the models as the major models are all showing broad agreement to T144 for PV locked to Greenland and a poor set up for cold conditions for UK and Ireland barring some chilly, dry weather which may be fed from the continent for a short period.

I think the idea of people playing with trends from day 10+ in the hope of creating a cold slant to their discussion are only fooling themselves.

over Gre

Models are showing High pressure build over us through the weekend giving widespread frosts which has indeed been a lacking feature this winter. I'll take this for a start regardless of what it being shown 10 days away.

http://nwstatic.co.uk/gfsimages/gfs.20120110/12/84/ukmintemp.png

http://nwstatic.co.uk/gfsimages/gfs.20120110/12/114/ukmintemp.png

[phil nw.]

Well it seems the models have stepped away from an Easterly solution for now but the immediate outlook is for colder conditions beyond Thurs. and into the weekend under a developing block.

Tomorrow remains largely dry and mild under the influence of the South Westerly airstream with the High centred near the English Channel.

The change to colder weather starts to the north on Thursday as a developing shortwave moves quickly across to the North of Scotland towards Norway with the Cold front clearing South across the Uk by midnight.

This introduces much colder Polar air across the whole country and as the High builds back across the UK by Friday it locks the cold air in and with rapid surface cooling some night frosts will occur widely over the following few nights and some cold bright days inbetween.

As we can see from the above images some quite cold air expected within 72hrs.

The trend now by all 3 main models is to attempt to push the blocking High eastwards by T120 as a renewed northern jet starts to bring in the Atlantic again,although by T144 the GFS is more keen on developing a strong zonal flow than the Euros who keep things more settled with high pressure never far away

Again still much uncertainty with the pace of change after the weekend.The PV still looks stubborn over Greenland but the resiliance of the blocking high is still not resolved fully with the Euro models much more reluctant to move it away around T120-144.

I think for now we need to see how this is resolved.

Edited January 10, 2012 by phil n.warks.

[Matty M]

Of course things could change again but the time is thinning.

You are looking at charts at T36 to T72 now for a change for a chance of cold spell synoptic in the next 10 days.

[tinybill]

i know its deep F1 but with a low of 965 over ireland for jan 26i think its something got to be kept an eye on

[Damp and dreary]

H, this is nothing on some of the years gone by.

Basically, one of the leading models, the American GFS, was showing a cold easterly on it's 12z and especially it's 18z run last night. This was not supported by the other models and now all the models have shied away from this scenario, with Atlantic dominated weather assuming control again after this high pressure spell.

Factors further down the line may lead to more promising charts over the coming days - but for the time being the large blue and purple bit someway to the top left of the UK remains dictating matters.

Thanks Ian for a concise explanation. Im guessing with all this swapping around that the shorter term outlook could still change with the next lot of runs?

[Duane S.]

I still think too many people are too quick to write this off. Most synoptics, a slight change here, a slight change there at T48(ish) and T90(ish) won't change too much. Not the case here. It really won't take much to swing the balance early on then we could be heading down a completely new road to what most models have been showing us today. i.e. if the vortex edges a bit more west into Baffin, the energy in the States is a little more reluctant then it could tip the balance completely. Not over yet, I still think there is maybe a 30-40% chance we are going to see a last minute major turnaround. And if not, we will get further chances down the line.

[cold snap]

ive got a funny feeling that the 18z is going bring back a easterly.its only a feeling mind.we shall see.

I think the ukmo could lead to a good solution down the line

[Matty M]

i know its deep F1 but with a low of 965 over ireland for jan 26i think its something got to be kept an eye on

Seriously? You honestly think it is something to keep an eye on! It is a 360 hour forecast from a single GFS Ensemble?

Right i will shut my trap but sometimes i can help myself!

[Zenarcher]

Review on the weather models this evening,

GFS

Pretty good model agreement but only up to just 72 hours. After this the low we have in the Atlantic the GFS wants to push it up North and all the other models agree on it moving South or pretty much disappearing so the GFS is on its own here. Once again at 120 hours the GFS seems to struggle to agree with most models. It creates a larger PV with 2 lows in that area. This is something no other model supports in fact all the other models have excellent agreement on just one large deep low in the PV area. For the GFS beyond 144 hours into early next week it still has these 2 lows in PV moving around with another low pressure riding the jet stream. This low then enters PV and joins one of the lows to create a deep depression to the West of Scotland bringing storm force winds. Again the GFS is on its own with this one. The longer range for the GFS shows a cold pool of air over the UK bringing snow. However with disagreement as early as 72 hours this doesn't seem to be likely at the moment.

ECM

Excellent model agreement up to 120 hours with the GEM, JMA and UKMO agreeing with it. At 120 hours it has the low move South down to France area which leaves the UK under high pressure. On its further outlook for the weekend and start of next week its looking settled for most of the UK with perhaps some night frost and clear sky possible. Looking ahead in 10 days time the ECM for the third time in a row is very keen on bringing changes with high pressure building up in the Atlantic and cold air coming down from the North.

JMA

Good agreement with the ECM with some disagreements from 144 hours and beyond. For the South of the UK its looking settled but unsettled at times for the North. Its longer range also seems to show high pressure build up in the Atlantic.

GEM

Another model mostly agree with the ECM up to 144 hours. However at 144 hours it does show a stronger deep low in the PV.

NOGAPS

It isn't exactly to keen on settled weather for the UK. with low pressure crossing over England next Tuesday bringing wet and windy weather and a strong PV to the South of Greenland.

UKMO

Today we have seen some changes in it with it finally agreeing with the ECM. It shows settled conditions for the South and perhaps a bit unsettled to the North.

Overall from now to the weekend it looks like it will be settled for most. Into early next week at the moment its mostly looking like the North of the UK may be unsettled at times meanwhile the South will be calm and could see some night frosts. In the longer term in about 10 days time around the 20th of January most models hint on a change most seem keen on building up high pressure in the Atlantic and it may perhaps lead to a Northerly. Also tonight we see more model agreement with ECM, GEM, JMA and UKMO all in one boat together. Meanwhile GFS and NOGAPS are left alone on their theories.