Model Output Discussion

[swilliam]

The GFS is finding its own way to scupper the easterly (to be fair several of these options were showing on the ensembles)

[sandstorm2]

Game set and match to the atlantic according to the ECMWF and the UKMO, even the GFS at +168 is caving in.

SS2

Edited January 30, 2010 by sandstorm2

[damianslaw]

It is a difficult situation to call at present. With the atlantic trying to roar into action after its dormant state for weeks and weeks now, whereas at the same time the major blocking over west russia is trying to exert its influence westwards as it has been trying to do for about 2 weeks now, but inbetween we have a complicated feature i.e. trough just to the east of the UK with associated low heights. Its this feature which is causing all the difficulties, we need the trough to move a more south east position allowing the lower heights to sink into europe. If this can happen then the GFS evolution would be more than likely as it will clear the path for the the heights out to the east to advect westwards, at the same time we will see undercutting of the atlantic front with a south easterly flow which will also allow for those crucial heights to develop over Greenland which is what we need if we are to get a long sustained cold spell.

However, if we just see the trough remain in situ, this will allow the atlantic to move through with associated southerly/south westerly airflow.

I still firmly believe the longer term evolution will be for heights to build strongly to the north as we head into the second week of Feb, and we will be staring at a sustained cold potentially very cold and hopefully snowy outlook, it may be a stuttering evolution, but we will get there in the end.

[nick sussex]

Whats so good about the 18z? We never get any very cold upper from the East, and the Atlantic is pushing East, knocking on the door basically.

You don't need very cold upper air for snow with this set up, given the horrors of the UKMO this evening most people will just be relieved that the GFS hasn't followed it in the earlier stages.

[Jason M]

Looks virtually identical to 12Z at around 160 hours.

Lets see how it pans out, but I'd certainly bank the 120 hour chart and in a situation this complex, anything after that has limited value IMO.

Jason

[The PIT]

Well two out of three major models go for Atlantic control lesser model like GME agrees so GFS very much out on it's own. The only other model that agrees with the GFS to a point is the JMA.

Odds favour the Atlantic pushing in and as long as it's stormy I don't care we've had two cold months and really getting greedy for three.

[PB22]

FAX charts out, and they go with the ECM model tonight:

T+96: http://www.meteociel.../fax/fax96s.gif

T+120: http://www.meteociel...fax/fax120s.gif

I can't see much hope there for an easterly from that T+120 chart.The UKMO 6 - 15 dayer will surely catch up tomorrow now.

Edited January 30, 2010 by Paul B

[Lewis]

You don't need very cold upper air for snow with this set up, given the horrors of the UKMO this evening most people will just be relieved that the GFS hasn't followed it in the earlier stages.

I don't understand, that's why i get so confused.

Everyone was ramping the place down because of a huge easterly showing on the models deep in FI, the GFS was showing this for days, for only the UKMO and the ECM to say no.

We are not looking the GFS, in short range upto T96 nothings changed at all if you match the 18z to the previous GFS runs, spot on with the under cutting etc.

We then get to the time frame where the previous runs was showing an Easterly on earlier models, and now the GFS shows the Atlantic breaking through, with the block not holding out. So, the GFS has followed the ECM/UKMO output has it not?

Do people actually know what they want lol?

Too me, staying cold, some frontal snow possible, before warming up, with the Atlantic breaking through.

[cooling climate]

Tomorrow evening we should have the answer to this enigma, as for the 18z I think its

gone walk about.

Start afresh tomorrow I think. Nite all.

Edited January 30, 2010 by cooling climate

[Ben_Cambs]

GFS seems a pretty confused model tonight, deep in FI brings in cold continental air We will see what happens tomorrow

Edited January 30, 2010 by Snowman0697

[Mark Bayley]

Short to medium term the GFS remains good, that's all we can ask for. Longer term we lose the colder air, nothing like the ECM though with temps remaining around average:)

In fact a low undercuts at T252 bringing back the south easterly flow.

Will the GFS back down in the morning? We shall have to wait and see

Edited January 30, 2010 by mark bayley

[The PIT]

I don't understand, that's why i get so confused.

Everyone was ramping the place down because of a huge easterly showing on the models deep in FI, the GFS was showing this for days, for only the UKMO and the ECM to say no.

We are not looking the GFS, in short range upto T96 nothings changed at all if you match the 18z to the previous GFS runs, spot on with the under cutting etc.

We then get to the time frame where the previous runs was showing an Easterly on earlier models, and now the GFS shows the Atlantic breaking through, with the block not holding out. So, the GFS has followed the ECM/UKMO output has it not?

Do people actually know what they want lol?

Too me, staying cold, some frontal snow possible, before warming up, with the Atlantic breaking through.

GFS doesn't show the Atlantic breaking through. It shows a good battle going on but it's probably putting the jet stream far too south so we need shift everything upwards a few 100 miles anyway. I would discount the GFS as it's very much on it's own.

[Cheese Rice]

The GFS has backed down at t168 allowing the Atlantic to break through somewhat, which I was really hoping wouldn't happen. It's no big deal though, as the easterly was quite far of, thankfully this didn't happen in the reliable time frame. I did think for a number of days the easterly was 80% likely but as shown never trust the models this far out. I wouldn't rule out the easterly showing again in the reliable time frame, it's still a chance, albeit small.

If everything comes together as shown I would be happy with this, frontal snow is my favourite type of snow event as we can do really well.

Edited January 30, 2010 by 10123

[Ben_Cambs]

Lol new trend deep in FI, brings a Easterly/North Easterly. Please come at some point!

[igloo]

games up i feel looking very like the euros past +168 the monster low in the atlantic is just to strong and will barge everything away but then again the models have a tendency of over powering these lows at such a time frame

[Tom D]

Oh dear oh dear... the op gets there in the end albeit about as deep in FI as it could be. I can't make any sense of this now, can any of the more experienced members? Just leave it until tomorrow morning eh?

[nick sussex]

I don't understand, that's why i get so confused.

Everyone was ramping the place down because of a huge easterly showing on the models deep in FI, the GFS was showing this for days, for only the UKMO and the ECM to say no.

We are not looking the GFS, in short range upto T96 nothings changed at all if you match the 18z to the previous GFS runs, spot on with the under cutting etc.

We then get to the time frame where the previous runs was showing an Easterly on earlier models, and now the GFS shows the Atlantic breaking through, with the block not holding out. So, the GFS has followed the ECM/UKMO output has it not?

Do people actually know what they want lol?

Too me, staying cold, some frontal snow possible, before warming up, with the Atlantic breaking through.

You've answered your question in the third sentence, thats all that matters for the timebeing. Theres no way to a colder set up with the UKMO raw output or at a stretch we'd all be drawing our pensions by the time it could evolve into anything cold!

Edited January 30, 2010 by nick sussex

[andymusic]

it's still playing with the blocking idea/easterly cold - need to see the ensembles on this to decide where this run sits

[MR EXTREMES]

Whats so good about the 18z? We never get any very cold upper from the East, and the Atlantic is pushing East, knocking on the door basically.

im sorry but are you serious or is this a joke post.

[NorthantsSnow]

I think swilliam summed it up well when he said the GFS has found its own way to scupper the easterly. The very same model that has been bullish about it for at least 90% of the runs it has produced for the past 4 or 5 days.

Given that the easterly now has no support from any of the major models, it looks to be a major longshot. And if the position is no different this time tomorrow, then I think we can safely conclude that it's not going to happen, however much we may wish for it to occur.

[PB22]

To me the GFS 18z tonight is merely starting its backtrack towards the European models, further confirmed by the FAX charts just released. Its now looking odds on for the Atlantic influence to be our main player by the end of next week and this episode will be remembered as yet another what could have been. Once again it shows that the UKMO model must never be dismissed. It never really brought the easterly idea, and although its probably being too progressive tonight, it looks like it will be nearer the mark in the end.

For easterly hunters, check out the 18z GFS beyond T+324!

[weather eater]

Interesting 18z, I suspect many will cry oh dear following the euros, except that’s not really true, as the run gets past the period where it all falls apart on the UKMO and ECM, then it drops the cold pattern only to pick it up again towards the end of the run. I don’t know whether some sort of BFTE is about to emerge, but I still think there’s a lot of mileage in the tank to keep all but the most pessimistic interested, fascinating stuff in my book.

[Grimsby Snow Lover]

Regarding the current gfs output. I can see why some poeple on here are a little disheartened regarding any easterly possibilities, however up to thursday/friday next week the run is not that different from the 12z run with some degree of easterly component. I personally try not to look to far into the future as these events always seem to changes quite drastically. IF the block to the east puts up a fight like it has done recently then the prospects for next weekend could be very different to what is been shown. Its just a pity the gfs is on its own at the moment. Perhaps in the morning we will know a little more. All is not lost just yet.

Edited January 30, 2010 by Grimsby Snow Lover

[Duncan McAlister]

Game's up now the ECM has sided with the UKMO, in my view. The evolution on the GFS looks dodgy as well. But the ECM 240 shows all may not be totally lost for the month of February as the high rebuilds in Northern Russia?

[shiver]

FAX charts out, and they go with the ECM model tonight:

T+96: http://www.meteociel.../fax/fax96s.gif

T+120: http://www.meteociel...fax/fax120s.gif

I can't see much hope there for an easterly from that T+120 chart.The UKMO 6 - 15 dayer will surely catch up tomorrow now.

yes but that makes the fax an outlier many twists and turns to come