Model Output Discussions 06z 04/11/16

[drm]

7 minutes ago, Ravelin said:

Maybe so, but you get the feeling that at some point this winter something just as crazy looking as that might just happen. 

the russian high losing its hold maybe

[Man With Beard]

That is one interesting GEFS set, and one that is starting to provide a little more direction for the months end. D10 - overwhelming trend to have a trough off NW Iberia, with heights to its north. At this stage, enough warmth being pumped up from the eastern side to prevent it being too cold. (This looks very likely to happen now, given the clustering in the ensembles.)

Just two days later though, D12 - a large number of ensembles are about to drop the bomb. Eastern heights closed off to the south and retreating westwards. Allowing an Arctic trough to drop into Scandi ... BANG!

 

[Frosty.]

The GEFS 18z mean looks excellent towards the end of November, as did the 12z!

Height rises to the NW..check. .. scandi trough..check..nice negative tilt. check...colder and colder with an increasing chance of snow..check

Edited November 15, 2016 by Frosty.

[Sperrin]

Something definitely brewing towards the end of the month according to the 18z. The ensemble graphs for my area (Co Tyrone) showing excellent snow potential for later this week (100% chance on the 17th ;-) ) and the end of the month. A downward trend in temperatures looks the form horse. 

[A.J]

some informative posts this evening from several members, keep it up, great to see!

on the flip side, there's been plenty of one liner posts that add nothing...Come on people, play the game, adhere to the few simple guidelines we have in place, and rather than dribbling over some posts, just hit the like button instead, or better still, pm your undying love privately and leave this thread to sensible posts that actually aid the discussion...I hate to sound like a broken record, but................

[Geordiesnow]

Really interesting 18Z run I have to say and I don't mean the FI shannagans either.

First things first, the 18Z has made the -5hpa cold pool a bit wider for the upcoming chilly snap, presume very low thicknesses is playing a part here so once again theres a risk of perhaps some lower level snowfall as the trough starts to fill and becomes more flabby so if there are any disturances in this flow, then with lighter winds, cold air overhead and low thicknesses then the risk of a surprising snow event is there but its far too early to know for certain and the ECM does not quite has this cold pooling so caution is very much needed here.

Theres no deep low on this run either but again, I would not rule it out in future runs though however I think the likely outcome will be low pressure near or over the UK but nothing out of the ordinary.

The southerly flow for early next week is gathering some pace however I would not treat this as bad news as it means the Russian high is drifting more to a Euro high however this helps to lower heights over Scandi and get some colder air to head down again and if things upstream in the Atlantic goes the way we want it too, then that Southerly could easily be replaced by a colder Northerly/NE'ly. Conversely, if things upstream does not go our way, then we may end up in the milder southerly theme for longer.

Of course, we could have something like the ECM where the southerly flow is much further East and we are under the cooler Atlantic troughing but still way too early to know for certain what the trend will be.

[Gael_Force]

On 07/11/2016 at 22:16, Gael_Force said:

I know you cannot show the weatherbell ensembles but maybe you can explain what's shown on the ECM 336 mean from this morning.

Is that 536 (500-1000) thickness over the UK?

 

It's not happened just yet but still looks like a good call for extended ECM means.

552 line down into Spain.

[northwestsnow]

Not posted today as my laptop at home has crashed but some very exciting GFS/GEFS on offer, the only fly in the ointment was that 12z ECM op - do not want to see that repeated tomorrow

[Mucka]

Starting to look like we will have secondary low pressure running along the base of our trough across the UK. Indeed GFS doubles down this morning so definitely some storminess to watch out for. I expect we could of seen quite a big transient snow event had we been in the depths of winter.

 

As far as the big picture goes both UKMO and GFS build much stronger Atlantic ridges than last nights ECM so hopefully ECM will drop the flatter progressive pattern from last night.

GFS 192, now that's a ridge!

264 Arctic flood gates open. Worry about uppers if and when we are lucky enough to see something like this.

Ice day in November?

GEM also much more amplified. Are things slowly coming together for cold fans or many more twists and turns to come?

 

Edited November 15, 2016 by Mucka

[northwestsnow]

40 minutes ago, Mucka said:

Starting to look like we will have secondary low pressure running along the base of our trough across the UK. Indeed GFS doubles down this morning so definitely some storminess to watch out for. I expect we could of seen quite a big transient snow event had we been in the depths of winter.

 

As far as the big picture goes both UKMO and GFS build much stronger Atlantic ridges than last nights ECM so hopefully ECM will drop the flatter progressive pattern from last night.

GFS 192, now that's a ridge!

264 Arctic flood gates open. Worry about uppers if and when we are lucky enough to see something like this.

Ice day in November?

GEM also much more amplified. Are things slowly coming together for cold fans or many more twists and turns to come?

 

Very happy with that GFS run

Extensive High lat blocking and southerly tracking lows- UKMO i'm not entirely convinced about at 144, the Russian High doesn't look as well orientated as GFS at the same timeframe - i'll pass that one over to the experts, i may be wrong,hope i am !

[SMU]

Morning

A quick peak from under the covers reveals a GFS run that from a Northern Hemisphere perspective is on the same level as Nov 2010- just no quite as cold for the UK

The greenland block is impressive at 192 onwards however the latter states of FI shows an increasingly epic -AO

ahead of them -A stormy period followed by the potential ridge to greenland...

some spectacular charts !

S

pS- expect a further downturn in the AO ensembles today - maybe some -4/-5 runsbin there!

Edited November 15, 2016 by Steve Murr

[knocker]

Today

The front continues it's journey south bringing some intermittent rain and drizzle as it does. So mainly cloudy in England and Wales and quite mild south of the front but cooler and clearer weather behind with some showers in Scotland.

The GFS this morning. Well first of all we need to keep an eye on the weekend and the possibility of stormy weather.

The large upper low pressure area in the eastern Atlantic duly stalls as amplification gets into full swing but importantly it is still being fed by energy emitted from Canada and thus perturbations form in it;s southern flank and track east within the overall circulation. Thus we have two vigorous surface lows tracking into the UK Saturday-Monday bringing some wet and quite windy weather to all but particularly the south. Possibility of some snow on the hlls in the northern flank of these lows but the precise track important as the the air is quite mild in the southern quadrant.

Where do we go from here? Well much as was indicated yesterday with amplification continuing apace and the Omega block forming as the UK trough is forced south. This initiates WAA into the UK and in particular Europe. This seems a good place to leave it but I suspect we are going to end up with the situation being indicated by the anomalies with HP to the north and LP to the south. Sidney is quite intrigued

.

[andymusic]

24 minutes ago, Steve Murr said:

Morning

A quick peak from under the covers reveals a GFS run that from a Northern Hemisphere perspective is on the same level as Nov 2010- just no quite as cold for the UK

The greenland block is impressive at 192 onwards however the latter states of FI shows an increasingly epic -AO

ahead of them -A stormy period followed by the potential ridge to greenland...

some spectacular charts !

S

pS- expect a further downturn in the AO ensembles today - maybe some -4/-5 runsbin there!

It can only get colder from there surely - some amazing output

[bluearmy]

Starting with the latest GEFS AO for steve

 

re the ECM 46 dayers

ian has already commented but to add that broadly the op and para are on the same page throughout. The para brings in winter a few days quicker and more akin to the current GEFS thinking. 

The cyclonic flow ian mentioned is centred between scandi and Scotland on the anomoly. On the para it is more sceuro which I believe cuts down the chances of it ending up too west based -NAO for the UK. 

T2's are average or below from week 2 onwards and if anything the model goes a little colder surface temps approaching Xmas as a renewed pulse from the ne comes around the euro low anomoly. 

i wonder if mogreps is seeing this? In the past, it was always a little behind the curve on picking up winter but that also meant it was ahead of the game when ithe cold didn't arrive! 

[knocker]

The ecm, although different in detail is in the same ball park as the GFS this weekend.

It has a developing upper low south of Iceland in the western flank of the upper trough which phases in with energy tracking from Canada and by 12z Saturday we have a developing surface low just SW of Ireland.  This moves quickly east and deepens and by 06z Sunday is 966mb over Birmingham bringing some strong winds and a fair bit of rain with it.  As mentioned previously the precise track quite important as there is a marked temp contrast between the northern and southern segments.

Thereafter the ecm differs from the GFS as the Omega block leaks and energy from Canada continues to get through resulting in the arrival of another trough by the middle of next week

[jvenge]

27 minutes ago, bluearmy said:

Starting with the latest GEFS AO for steve

 

re the ECM 46 dayers

ian has already commented but to add that broadly the op and para are on the same page throughout. The para brings in winter a few days quicker and more akin to the current GEFS thinking. 

The cyclonic flow ian mentioned is centred between scandi and Scotland on the anomoly. On the para it is more sceuro which I believe cuts down the chances of it ending up too west based -NAO for the UK. 

T2's are average or below from week 2 onwards and if anything the model goes a little colder surface temps approaching Xmas as a renewed pulse from the ne comes around the euro low anomoly. 

i wonder if mogreps is seeing this? In the past, it was always a little behind the curve on picking up winter but that also meant it was ahead of the game when ithe cold didn't arrive! 

Ha, the control started celebrating Christmas early. Not a bad mean, though. ECM closer to the GFS mean than control. 

[Frosty.]

The GEFS 00z mean is another cracker towards months end with height rises to the NW, a blocked atlantic and a scandi trough. The 00z control run isn't bad either!

Edited November 15, 2016 by Frosty.

[Day 10]

Can't post any charts at the min, but things really are building nicely. The gfs 192 Mucka has posted looks a cracker followed by the 264 even better! The reports from the strat just get better and better. Hope to have a good look at the charts later. There definately is an air of 2010 this year, exciting times. 

[bluearmy]

Incidentally, the ecm track on Sundays system took it up the channel with a covering on the South Downs!!

[beng]

12 minutes ago, bluearmy said:

Incidentally, the ecm track on Sundays system took it up the channel with a covering on the South Downs!!

Just to clarify, do you mean the parallel ECM Blue?

[Weegaz]

images like this showing this early are giving us great hope across the water, long may they continue

[Grimers]

Coming back to the more predictable future, the ECM model shows a severe storm moving into SW parts of the UK on Sunday, there's the potential of hurricane force wind gusts likely in exposure, this is something we haven't seen since 2014!

[bluearmy]

6 minutes ago, beng said:

Just to clarify, do you mean the parallel ECM Blue?

Sorry - yes (my bad as the youngsters say)

yesterday's 12z para

 

[BLAST FROM THE PAST]

Well a quick one for mw but mention has to be ECM.  What a run and another after 12z showing the secondary deep LP crossing southern UK.  And at t120!!! 

Very happy with the way this month has turned out and appears to be developing.  

3/1 for snow at Aberdeen airport and 5/1 for Toon on Xmas Day.......banker 

I note MetO have taken note!!!

BFTP

Edited November 15, 2016 by BLAST FROM THE PAST

[Summer Sun]

13 minutes ago, Grimers said:

Coming back to the more predictable future, the ECM model shows a severe storm moving into SW parts of the UK on Sunday, there's the potential of hurricane force wind gusts likely in exposure, this is something we haven't seen since 2014!

 

40% chance of severe gales in your part of the country