Model output discussion - into 2018

[northwestsnow]

1 hour ago, Steve Murr said:

Look at the 120 Bracknell fax..

Cheers mate...so what the hell are Exeter talking about ?

[Dancerwithwings]

Come on models get your acts together....All this talk of climatology and endless definite possibilities of an immanent beastly/easterly on it's way is starting to get a little

All a know is that I would love to see that cold air over eastern parts of Europe 'AT SOME POINT' just make it to the UK

[Frosty.]

According to the GEFS 6z mean we are looking at predominantly cold zonality though low res, especially further north with a generally polar influence with a risk of snow at times.❄❄❄❄❄❄❄❄❄❄❄❄ 

Edited January 7, 2018 by Frosty.

[shaky]

53 minutes ago, Steve Murr said:

Read Gael force post

Steve pretty big gfs 12z coming out now you would think!!if it improves then i think more than likely ecm and ukmo are on to something here!!if it doesnt then ecm and ukmo are probably leading us up the garden path here again!!it has to start on the 12z now!!!icon coming out now!!!

[bluearmy]

20 minutes ago, northwestsnow said:

Cheers mate...so what the hell are Exeter talking about ?

Well that was based on yesterday’s 12z run and they generally don’t amend the raw output unless they really feel the need to

If the 12z run is consistent then tonight’s issue will be worth waiting for to see if they go with it 

[Dean E]

3 minutes ago, Frosty. said:

According to the GEFS 6z mean we are looking at cold zonality though low res, especially further north with risk of snow at times.❄❄❄❄❄❄❄❄❄❄❄❄ 

Indeed @Frosty., I was about to post the same sort of post!

A general outlook next week from all the Models so far from this morning is we basically have a chance of 2 scenarios...

1. A less pronounced Scandinavian block with a higher chance of Atlantic Zonal attacks, but moving more NW to SE direction. Akin to December 2017. (GFS is still out on its own with this)

2. A stronger Scandinavian block with a threat of a Easterly wind bring much colder uppers in from Russia. (ECM/UKMO)

Either way, the block never really leaves to the NE until post 192h on all models. With the GFS then going for cold zonal again in FI.

The GFS (as @Steve Murr  has been predicting for sometime now) is slowly moving more towards the ECM and UKMO, especially in the reliable timeframe.

I think the ECM needs time to adjust that breakdown, but that's miles off for now.

But as always, get the cold in first! (Its already below average for most of the UK today!!!!!!)

[booferking]

31 minutes ago, northwestsnow said:

Cheers mate...so what the hell are Exeter talking about ?

Not quite sure why so much talk about 120 fax chart it fits in nicely with there forecast you can see the fronts approaching Ireland & Scotland thursday then likely to give transient spell of snow across the Scottish mountains later on Friday and into Saturday then after it's likely zonal and maybe cold zonal at that?

Edited January 7, 2018 by booferking

[Paul_1978]

“How this block breaks is rarely  as simple as models suggest, and expect flips at short lead times” is very telling. 

Edited January 7, 2018 by Paul_1978

[Matthew.]

1 minute ago, Paul_1978 said:

“How this block breaks is rather as simple as models suggest, and expect flips at short lead times” is very telling. 

I always think stick to the models 5-7 days out and watch the story unfold. The rest no one knows until the next models run come out and the general consensus

[SMU]

11 minutes ago, shaky said:

Steve pretty big gfs 12z coming out now you would think!!if it improves then i think more than likely ecm and ukmo are on to something here!!if it doesnt then ecm and ukmo are probably leading us up the garden path here again!!it has to start on the 12z now!!!icon coming out now!!!

Yes - I would like to zoom in on the T96 timeframe that’s where most of the GFS is seemingly doing its damage

 

The 2 shortwave need better seperation which in turn will allow the Scandi block to naturally filter NW...

icon better up to 66-

[Duane S.]

Blimey this forum is excruciating reading at times. If certain people are only here to pick faults at synoptics and posters who spent time and effort explaining their thinkings then, with the greatest of respect, it may be best they head to the ramp and moan thread until a cold set up is closer to being set in stone. No coincidence they offer up little or no counter reasoning to back up their constant gloomy outlooks, only interested in gaining some sort of ‘recognition’ for being right about predicting default UK weather. Whoopy do.

Take a leaf out of @danny above, who is not buying the quick emergence of an Easterly, but at least has taken the time and trouble to outline his thoughts as to why it most likely will not occur.

FWIW, my money is only on an absolutely fascinating period of too’ing and fro’ing. Why can’t some just enjoy that?? I know I will probably end up being disappointed every time, but do the two things have to be mutually exclusive?

So what we’ve got is a proper east V west clash but not a standard one. A powerhouse Atlantic v a building block to our east. Has the block been underestimated? It often happens. The models ALWAYS struggle with these set ups. 

Even if the Atlantic does break through, there is no SW blowtorch zonal train in sight. It is likely to introduce PM / cold zonality period of weather, on an increasingly southerly jet as we head through the month and then, with lower heights in Central Europe, the block to the east would be better placed to come back bigger and stronger with some proper CAA heading our way.

Anyway, here comes the 12Zs, where to next !?...

 

[alexisj9]

8 minutes ago, Matthew. said:

I always think stick to the models 5-7 days out and watch the story unfold. The rest no one knows until the next models run come out and the general consensus

Personally with current synoptics I wouldn't look more than a couple of day into models and even the second day could change a bit.

Edited January 7, 2018 by alexisj9

[bluearmy]

It should be noted that there has been little cold air associated with this blocking as it has been modelled thus far

if deeply cold uppers are advected into the equation around the south of the block then breaking it down becomes even more of an issue for the models 

[Snowman.]

Just now, bluearmy said:

It should be noted that there has been little cold air associated with this blocking as it has been modelled thus far

if deeply cold uppers are advected into the equation around the south of the block then breaking it down becomes even more of an issue for the models 

Isn't this due to colder air being denser?

 

[Derecho]

Good afternoon 

Quite a mix in the interpretation of the model output I see. I'm surprised at the amount of negativity given what some of the close range output could be building towards.

My last post itself was quite a downbeat one about the easterly this weekend and there were a couple of reasons for that.

1) The cold air outpouring from NE Canada has been firing up the W-E movement of low pressure systems coming out of the USA. Look at todays global temperature anomaly chart for example and its not hard to see why. This means any block is overwhelmed by the Atlantic.

2) Any easterly that did occur this weekend had a serious lack of cold air to tap into. The problem was during last week the stormy weather carried some exceptionally mild air across Europe.



So are things any different for this coming week?

The answer is yes, quite different.

First is the increase in colder air to our far east which should make some progress westwards and finally allow cold pooling over parts of eastern Europe. Look at the cold uppers on the ECM T120. Nothing to really write home about for January but far better then this past week at least. Secondly, the pattern across the North Atlantic has changed. Rather then seeing a west-east movement of cold air off Canada. We are now seeing cold air move south from NW Greenland into the Atlantic. Deep areas of low pressure will still form, however their direction may not be as zonal, so the block could come under less pressure.


So how do we get the UK to turn much colder? This chart explains the steps. Alignment of the Scandi high and the amount of energy going under the block are key. Here is the latest ECM at T120 for example.



I reiterate that the chances of this coming off are a long shot but this pattern should improve our long term prospects. There is the risk that the Atlantic may win out but this setup is more intriguing then this weekends poor easterly.

J

H 

[beng]

Just now, bluearmy said:

It should be noted that there has been little cold air associated with this blocking as it has been modelled thus far

if deeply cold uppers are advected into the equation around the south of the block then breaking it down becomes even more of an issue for the models 

What about this morning's UKMO output though - decent cold pool in place by t144?

[SMU]

So the focus time T90 ish

iKon 06z V Ikon 12z

notice the Easterly flow a lot stronger into Europe...

& magically the block is further north

Edited January 7, 2018 by Steve Murr

[Chesil View]

Its always interesting the read the differing views of posters looking at the output. I'm slways intrigued by the notion of what this forum would have been like in the run to 1947 or 1963 all other things being equal in terms of available model output etc.

[Gael_Force]

52 minutes ago, ArHu3 said:

Iirc that was glosea5, I was trying to find that presentation again but couldn't maybe someone else has a link

Glosea5 just recently added to the mix. Models and runs are shown below.

Quote

Decider is a flexible package, designed to suit your needs. We can update your Decider subscriptions with any of the following options:

• Web access to ECMWF 15 day forecasts – updated twice daily
• Web access to GEFS 16 day forecasts – updated four times daily
• Web access to ECMWF 32 day forecasts – updated twice weekly
• Web access to GloSea 51 day forecasts – updated daily
• Web access to daily historic weather regime classifications from 1850 to present (available to download in CSV format). This data can be used to correlate weather regimes with a parameter of interest where historic records exist, such as weather observations, cases of high impact weather and even energy demand or supply. Once a relationship has been established, it becomes possible to forecast the likely consequences given a forecast for a particular weather regime. The number of specific forecast applications is potentially large.

https://www.metoffice.gov.uk/services/industry/energy/decider

[bobbydog]

5 minutes ago, Steve Murr said:

So the focus time T90 ish

iKon 06z V Ikon 12z

notice the Easterly flow a lot stronger into Europe...

& magically the block is further north

lets hope the rest follow. its a tight situation to get to this easterly. despite my own doubts, i really do hope you have called this right. 

[SMU]

1 minute ago, bobbydog said:

lets hope the rest follow. its a tight situation to get to this easterly. despite my own doubts, i really do hope you have called this right. 

So do I-

GFS through 66 has better seperation this far -

[winterof79]

9 minutes ago, Broadmayne blizzard said:

Its always interesting the read the differing views of posters looking at the output. I'm slways intrigued by the notion of what this forum would have been like in the run to 1947 or 1963 all other things being equal in terms of available model output etc.

Wretched Azores high and winter is over would have been the call In December 1946

 

 

Strange similarity don't you think as the new year came in

 

Few days later

We can but dream.....come on Scandi you can do it

[karyo]

The updated ICON brings a cold westerly by the end of the run (180 hours). No sign of an easterly there.

http://www.meteociel.fr/modeles/icone_cartes.php?&ech=180&mode=1&map=0&archive=0 

Edited January 7, 2018 by karyo

[Singularity]

 

All the small things... they count in situations like this. The LP by Iceland is further west and as Steve has just noted, the LP by the UK is separating a little better.

How much it counts, well that comes down to the model as much as anything. Some models will adjust more than others following such tweaks.

A truly fascinating period upon us with major shifts of momentum and forcing patterns too and fro.

Well then - a closed isobar for the southern LP already. I have been skeptical of our easterly chances (for several days now, a chilly ridge outcome has been my 'safe estimate') for sanity's sake but I am starting to wonder if the westerlies might just be subdued enough in our vicinity... hmm.

[Frosty.]

2 minutes ago, karyo said:

The updated ICON brings a cold westerly by the end of the run (180 hours). No sign of an easterly there.

http://www.meteociel.fr/modeles/icone_cartes.php?&ech=180&mode=1&map=0&archive=0 

A cold westerly ties in with the GEFS 6z mean which shows cold zonality  becoming more likely beyond the week ahead!