Model Output Discussion:

[Methuselah]

Please continue: and remember to discuss model moods in the appropriate thread!

Previous:

[bluearmy]

i note a few posts re the 12z's will be crucial - i disagree. i think it will be tomorrows. (i'm out of internet range until then!!)

incidentally, the NAEFS 00z now puts us is 'no mans land' until fi and then the interaction between the atlantic and continental is shown a couple of hundered miles further north. still bags of potential but the trend towards -NAO west based with us missing out is intensified a little from that.

[s4lancia]

FAO BFTP, here are the 850's as promised...

[TEITS]

Speaking of model disagreement we can also see the uncertainity in the GEM/NOGAPS.

http://www.wetterzentrale.de/pics/Rgem1681.gif

http://91.121.94.83/modeles/nogaps/run/nogaps-0-168.png?30-06

Talk about chalk and cheese!

i note a few posts re the 12z's will be crucial - i disagree. i think it will be tomorrows. (i'm out of internet range until then!!)

.

When I say crucial I mean with the UKMO continuing with its trend. If we are to see an E,ly then we need the 12Z UKMO back away from its current trend. If tonights 12Z remains the same then my confidence will take another knock.

[chionomaniac]

The models are having certain difficulties in deciding where any blocking is going to occur as a result of effective propagation from the stratospheric warming. This should be taken into account over the next few days. With the AO tanking negative big time we know that blocking is going to occur just not exactly where!

[cooling climate]

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Posted Today, 06:50

KTtom, on 30 January 2010 - 06:33 , said:

You have to laugh, or cry, at the models sometimes! Just as the GFS produces an almost identical medium term run to the 12z ECM with a battle royal with a block to the NE and weather systems trying to push up from the SW, the 00Z ECM totally ditches the idea and blows the block away!

UKMO is even worse, in fact is miles away from cold at +120 and +144.

There is a massive scatter on the GFS ensembles for London, but overall no where near as promising as they were.

The models are confused thats all, that do not know yet what happens to the troughing

and energy in the atlantic as the block moves west. The big three models are different to

each other which shows they are struggling, the same happened to the troughing over

Scandinavia.

This issue I think will be finally sorted by the end of the weekend and whether that means

the cold is delayed by a day or two I do not know but I am still as confident as ever the

block and the cold is coming.

What we are seeing is just a wobble by the models nothing has changed, it is the result

probably of more energy coming off the SE of America and the models have over reacted.

The bitter winter weather is just as likely now as it was last night.

[TEITS]

The models are having certain difficulties in deciding where any blocking is going to occur as a result of effective propagation from the stratospheric warming. This should be taken into account over the next few days. With the AO tanking negative big time we know that blocking is going to occur just not exactly where!

Whilst I agree with the above the big difference at the moment between the UKMO/GFS is what happens to our W.

Clearly see the difference between the UKMO/GFS at +96!

http://www.wetterzentrale.de/pics/Rtavn961.png

http://www.wetterzentrale.de/pics/Rukm961.gif

[Iceberg]

A better 06Z out to T102. Less energy coming into the Atlantic and a slightly better tilt. Quite similar to the 00Z though, but a bit better at that time range.

BTW thanks Fred for your comment in the other thread. :lol:

[s4lancia]

The models are having certain difficulties in deciding where any blocking is going to occur as a result of effective propagation from the stratospheric warming. This should be taken into account over the next few days. With the AO tanking negative big time we know that blocking is going to occur just not exactly where!

Hi Chiono, I certainly agree with that, northerly blocking, and plenty of it, almost certainly will now occur as we get into Feb. What's your take on where it will end up predominately being?

[Guest North Sea Snow Convection]

The UKMO party pooper as I called it yesterday is doing its best again it seems.

The answer in all this may be that neither mild south westerlies or very cold easterlies result. The end product could be relatively high pressure close by with frosts at night. Perhaps.

I think that next week will show some initial atlantic incursion, so the modelling up to t96/120 is perhaps along the right lines. However, following that it is quite likely that blocking will develop. However, there is uncertainty about the position of that blocking and I am not sure that the mechanism is still in place for the very cold air from the east to get here. A west based -NAO and an eastern block look a possibility with a chilly SSE airstream maybe is the end result?

To much criticism (and misrepresentation) I said a week ago that the peak of the winter cold may have passed by. I will stick to that, at least for the time being. In my eyes the perfect teleconnectic and global conditions of the first half of the winter have gone and we may just have to accept average cold spells/snaps for the remainder.

That is not a winter is over post, perhaps some reality. We will see.

[BLAST FROM THE PAST]

FAO BFTP, here are the 850's as promised...

Thank you, it is armaggeddon and I just wanted to keep it. On file now thanks to you.

BFTP

A better 06Z out to T102. Less energy coming into the Atlantic and a slightly better tilt. Quite similar to the 00Z though, but a bit better at that time range.

BTW thanks Fred for your comment in the other thread.

No need as it was spot on, but you u r welcome.

Fred

[TEITS]

Well the 06Z certainly isn't going to be like the UKMO which is a relief.

Have to say based on the ECM ensembles and the 06Z so far I was too premature in dismissing the E,ly.

I just said to my mother on the phone who always asks for an outlook that it could be mild or sub zero temps with plenty of snow. She thought I was winding her up!

Clearly see this morning that the ECM ensembles/GFS/GEM have different ideas to the UKMO/NOGAPS. The plot thickens!

[Duncan McAlister]

The morning models always disappoint after being brilliant the night before, or at least that's how it seems *sigh*

But GFS has stuck with the easterly throughout, it was right about the northerly and the breakdown of the last cold snap so we'll see

[Iceberg]

At 120 the GFS now has quite a bit more energy going under the block, which is very nice to see and very different to the 00Z UKMET. All thanks to the slightly better tilt and less energy earlier.

However its a tightrope situation where even a few degrees difference in angle seems to have a big impact 72 hrs down the line, hence the ENS/EPS spread.

[East Herts Snow]

Well the GFS 6z run is showing small differences with the block slightly further West.

However small changes can bring big differences, with the Atlantic lows sliding further SE by +120 and colder uppers across more of the UK. Greenland High looks better as well.

I personally want it to warm up, but for cold lovers, this run looks like being an upgrade.

Edit: By +144 hours this run is an upgrade for cold, could be interesting for the Southern most counties (especially along the South coast), with the possibility of a English channel low.

[huntso]

To much criticism (and misrepresentation) I said a week ago that the peak of the winter cold may have passed by

Although very inexperienced in this model interpretation that was my take on it all

I agreed with you last week and do now, winter is still with us, but can't see a full blown reversion to extreme cold and think we may be seeing the encore rather than the main gig

[Lewis]

I more than anyone was dismissing the Easterly over the past few days.

But i was only doing this with it being so far out in FI.

Past 2 or 3 runs as we come closer to the projected time frame when the easterly was showing, has now showed a colder short term, so i think the block is set, and the trend starting especially for eastern areas come wednesday, now it's just down to the cold air in the form of the easterly really pushing East and of course if the Atlantic holds off, which i think it will.

[TEITS]

The UKMO party pooper as I called it yesterday is doing its best again it seems.

The answer in all this may be that neither mild south westerlies or very cold easterlies result. The end product could be relatively high pressure close by with frosts at night. Perhaps.

Morning Tamara.

I disagree with some points that you've raised. Personally in these situations its either the Atlantic winning or we see a very cold E,ly. I don't see an inbetween with this pattern. Also to get to a W based NAO then we are likely to see at least a spell of very cold NE,lys. However this would be less prolonged than some the of the E,lys currently modelled.

[nick sussex]

Well it's hard to believe the differences between the UKMO and GFS at 96hrs, normally this is a timeframe which the models can agree on. Anyway it is a relief to see the GFS 06hrs run not back the UKMO.

[Cloud 10]

UKMO>> GFS>>

The ukmo and gfs very different at +120 with the gfs shoving much more jet energy south.

The ecm seems about the middle ground between these 2 charts,so anything still possible.

[Lewis]

Very happy with the GFS upto now, short to mid term looking very good. No sign of milder conditions pushing in especially from eastern areas, from now until.. well who knows

Also what the hell is this on the gfs? a monster LP or a hurricane rofl.

[Bobby]

What a mess and what a rollercoaster. Worrying that the UKMO and GFS ensembles are looking not so good but the ECM ensembles are very good and the GFS 06z op is now looking very good too.

I do get a feeling that trying to get this easterly is like chasing rainbows though...

[Cumulonimbus Tower]

UKMO>> GFS>>

The ukmo and gfs very different at +120 with the gfs shoving much more jet energy south.

The ecm seems about the middle ground between these 2 charts,so anything still possible.

Yup, the GFS is being very bullish with regards to the cold not going anywhere fast with only a brief 24h less cold spell and very cold easterly by next Frifday as it slides any Atlantic influence under the block. 156h is a thing of beauty to me

[TEITS]

I do get a feeling that trying to get this easterly is like chasing rainbows though...

Looking at the differences between the models makes me realise why E,lys were a nightmare to forecast back in the 1980's.

What also makes the differences even harder to understand is the consistency of each model I noted Paul B said the UKMO had shown a similiar trend for the past 3 runs. However the GFS has been consistent for 14 or is it 16 runs!!

[Totoro]

I more than anyone was dismissing the Easterly over the past few days.

But i was only doing this with it being so far out in FI.

Past 2 or 3 runs as we come closer to the projected time frame when the easterly was showing, has now showed a colder short term, so i think the block is set, and the trend starting especially for eastern areas come wednesday, now it's just down to the cold air in the form of the easterly really pushing East and of course if the Atlantic holds off, which i think it will.

Wouldn't we prefer the cold air to push West and not East?