Model Output Discussion - 05/01/2016 18z onwards

[Mokidugway]

1 minute ago, Polar Maritime said:

Way out in the run, But it's nice to see the Highlands touching -14c 

 

Significantly colder with decent snow cover ...

[Glacier Point]

Not sure the GFS is handling this North American trough, or indeed the blocking over the Arctic too well at all. 06z and 18z runs seem to be particularly volatile on this with large inter run variation.

[Ben Sainsbury]

It's incredible to see the cold hanging on by the 19th so far!

The high pressure to our west in the Atlantic tending to edge closer to the UK.

With low pressure pushing into Greenland.

Edited January 7, 2016 by Ben Sainsbury

[rory o gorman]

2 minutes ago, PolarWarsaw said:

The low plays ball on this run...but as far as I can see, each run that gets closer to the time frame, waters the cold uppers out and delays them coming in.. the ECM last night and a couple of other runs in the last 48 hours had -7 uppers down over the centre of the spine of the country by Tuesday...then last night it's Wednesday...now it's Thursday and even then - they are modified. 

Not to be negative, the runs are very good - but these small features shouldn't go un-noticed. Its another very good run. But as far as I can see the main trend for today so far seems to be;

- Delay of the proper cold getting in.

- Snow chances reduced for the south/centre of England

- Colder uppers being modfieid to make things more marginal..

ONE HUGE Tick for the 6z..

- The low plays ball (thank god). 

 

 

 

Wrong. 

 

If someone said to me... I'll give you a 3 day cold spell, with temps hovering just on the marginal bracket, but you will get 2 systems that produce 5cm and then 8cm of accumulating snow...or I get 10 days of ice days, that are sunny and frosty but don't bring snow to anyone bar coast fringes and Scotland then I would take the first one with my eyes closed, enjoy it and then search for another spell. 

The greater majority of people want SNOW, not cold and frost. 

You realise that  the 'low' is entirely  different  from the one depicted in the 00z . This low forms as a result of falling heights and a 700mb vort lobe embedded within, known to many here as a 'trigger low' . Not related to the AZ trough on the 00z in any way. 

[Harsh Climate]

4 minutes ago, Nick L said:

Yes, but with considerably lighter winds. Evaporative cooling cannot happen to a sufficient enough level when winds are strong. If you want to read further I put a guide together on this subject...

 

 

 

Ok you make a fair point here. I still think that those charts would produce heavy snow for northern midlands/northern england (central areas) though 

[Frank Trough]

13 minutes ago, BLAST FROM THE PAST said:

Well 06z trumps 00z with what is simply a stunning run with GHP and Atlantic ridge in total and utter charge, how many more stunning runs before reality is confirmed?  Whatever reality will be

Snow event with shallow channel low.  The following chart is 'FREEZING' with I suspect bucket loadss of snow

I mean...come on

 

BFTP

If I didn't live in Bournemouth I'd be very excited. Reality for southern coastal counties at face value is a delay in really cold uppers and cold rain until well out of the reliable.

But I think a lot of people are going to be very happy come next week - exciting stuff.

[Summer Sun]

Taking in the wind chill next week its going to be feeling raw especially overnight and early on the mornings

 

[Harsh Climate]

Think I preferred the 00z to the 06z but all this run is is just one essemble member out of many effictively. The esembles are far more important than a single gfs operational run..

[SMU]

Ignoring the interun detail & the fact that the GfS is now touting the -10c isotherm all the way into England

this is the critical chart -

The secondary ridge over NE US at just 120....

nearly heading into the safety zone.....

s

Edited January 7, 2016 by Steve Murr

[nick sussex]

4 minutes ago, carinthian said:

Hi Nick, just been speaking to our snow portal service, they think that low just off the south of England to engage the colder air to the north may well go further south now, possibly into Northern France with  snow risk increasing across Southern England. All in all this would be the best option to prolong or even increase the cold. Western Alpine regions should have some good snowsfall early next week and transferring to the Eastern Alps later. We have forecast here of 50cm fresh snow by Friday am. Looking good, with the jet now going below 50N and there it best stays. Best see where tonights charts plot develop that snow potential for Southern England .

 C

Yes the more southerly low track will correlate with a better block to the nw. Unfortunately this won't please everyone because historically sustained cold in these types of set ups has low pressure tracking as you say in northern France and effecting more southern areas. The further north the low gets would be indicative of the block further west and possibly weaker.

 

[bradymk]

6 minutes ago, Glacier Point said:

Not sure the GFS is handling this North American trough, or indeed the blocking over the Arctic too well at all. 06z and 18z runs seem to be particularly volatile on this with large inter run variation.

Yes, comparing the day 10 charts (and before) for GFS and EC you can clearly see the difference in the modelling of the arctic high. ECM keeping a strong high over the Arctic and very close to the Greenland heights at day 10. GFS  has completely got rid of it by day 10 and at an earlier timeframe than showed too.

[Frosty.]

Good things are worth waiting for and the Gfs 6z eventually brings a snow fest to much of the UK. A few days ago this looked like being a day or two cold snap but I think the models are now firming up on a much more prolonged cold spell which is occasionally reinforced...winter is coming

[Karl83]

 For those who use Meteociel on their phones/tablets etc. There is an app on Android and iOS. It's well laid out and far easier to navigate through and has every chart you need.

Just thought I'd share this.

Edited January 7, 2016 by Karl83

[West is Best]

2 hours ago, johnholmes said:

Your post is not a true reflection on what any model is showing in the broad scale pattern of things.

 

Gloriously understated and restrained

Fred, great to be back. I'm a terrible fair weather friend in only appearing when the synoptics look good for cold / snow, which they now do. The 6z is another good run. We'll have ups and downs along the way but this is looking great and it doesn't look set to start in FI, but around T108.

[BLAST FROM THE PAST]

18 minutes ago, Certain kind of fool said:

If I didn't live in Bournemouth I'd be very excited. Reality for southern coastal counties at face value is a delay in really cold uppers and cold rain until well out of the reliable.

But I think a lot of people are going to be very happy come next week - exciting stuff.

You can't have it all CKOF......but I suspect you'll be joining in sometime

 

Richard, indeed we are within 'striking' range now

 

BFTP

Edited January 7, 2016 by BLAST FROM THE PAST

[Met4Cast]

Reading the posts in here this morning you'd think the models were showing full on zonality. The 06z is stunning and the way it handles the low over the Azores is perfect, no phasing and the low remains shallow. 

The ECM phases the two lows creating a deeper low which would mean rain for Southern England but blizzards for the Midlands Northwards. Even with this phasing the block is solid and cold air soons sweeps back into place. 

Stop looking at UK detail at this stage, there are two key areas to watch in order to get this cold spell nailed.

1. WAA up the Western coast of Greenland at T120, almost into the reliable. If this happens it's game on for the block.

2. The azores low at 144-168. Whether it phases or not will depend how cold the UK gets, but as long as step 1 falls into place the long term is good. If step 1 fails, the low wont really matter all that much anyway.

[inghams85]

The level of cold (850's) and longevity and strength of the Greenland block will only upgrade in the next 48 hours.

The reason for this is the models are MASSIVELY underplaying the strength of the arctic high pressure. (GFS especially)

An area models traditionally struggle with might I add.

As the Arctic high is modelled correctly closer to T-0 watch this push colder 850's down the spine of the country from the troughing.

 

[swilliam]

1 minute ago, Daniel Smith said:

Reading the posts in here this morning you'd think the models were showing full on zonality.

Not sure why you have said this. As far as I can see most of the posts have been discussing the position and strength of the block, the depth and longevity of the cold and the usual where will it snow/rain etc.

[Man With Beard]

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=6&ech=162&size=

Chalk and cheese between the 00Z ensembles and the 06Z ensembles at T162. Much less made of the Azores low - resultantly, much cleaner cold charts all round, with potential for sustained cold shown by most members.

[karlos1983]

9 minutes ago, swilliam said:

Not sure why you have said this. As far as I can see most of the posts have been discussing the position and strength of the block, the depth and longevity of the cold and the usual where will it snow/rain etc.

Indeed, We are discussing the Model output in the Model output forum......

The Azores Low is of particular interest, because depending on how it develops will depend on where it tracks, and if at all as the GFS has just shown. We shall see. (in terms of it ejecting another low towards NW Europe)

 

Edited January 7, 2016 by karlos1983

[Ben Lewis]

7 minutes ago, Daniel Smith said:

Reading the posts in here this morning you'd think the models were showing full on zonality. The 06z is stunning and the way it handles the low over the Azores is perfect, no phasing and the low remains shallow. 

Really? I have found the posts in here to be very informative this morning discussing how long/when the block will take hold. Just some members a little hesitant/cautious from the magnificent 12z  yesterday.

[Daniel*]

2 hours ago, Frosty. said:

Let the good times roll, stellar 00z output has strengthened my belief we are heading for a prolonged cold spell, these charts from the Ecm 00z...winter is coming with a vengeance, I have been itching to say that for the last 5 weeks...3 years .

For Southern England at least. 

[supernova]

55 minutes ago, Steve Murr said:

Ignoring the interun detail & the fact that the GfS is now touting the -10c isotherm all the way into England

this is the critical chart -

The secondary ridge over NE US at just 120....

nearly heading into the safety zone.....

s

Steve, looks important, can anyone help a grasping lurker understand this point in more detail? 

Edited January 7, 2016 by supernova

[Jeremy Shockey]

AO about to go very negative indeed. Havent seen that in a while ! ( since 2010 )

[Paul]

Please can we keep it to the models in here, plenty of other places to discuss meto forecasts and the like.