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ITSY
25 December 2015 22:37:38

Low Res 18Z shaping up well so far, albeit with the usual caveats. pressure lowering in SWern Europe and SEern Europe, coupled with the high cutting off over Scandi and inflating horizontally across Lapland. That is the combination of factors we want for a pure Easterly. Too many caveats and uncertainties to even consider it likely, especially the lack of cross-model and professional support for the scenario, but important things to look out for and recognise in coming runs.


EDIT: There are too many caveats to mention but the key things going wrong for us
- HLB over Scandi/Russia is 1,000 miles too far East
- the heights over S/C Europe are too strong to begin with - indeed this risks any block falling back into a Euro High or even a UK - both could be more likely than any Easterly (just experience talking, not stats before people shoot me down).
- the lowering of those heights over SWern Europe takes too long and is too far West. Unless any incoming cut-off low spins into the central/northern med region, the incursion of cold air further East will likely not get carried over the low towards Western Europe, and instead sink south over Turkey towards the Mid East.
- the HLB itself - need it to cut off earlier, the longer it hangs around over central Europe (without a cut off low to separate them from heights over Scandi) the harder it will be to advect meaningful cold in our direction
- finally, the Altantic is still a mean beast. So long as heights remain low over the Northern Atlantic everything has to run perfectly over Europe for us to override the impact of our warm and cyclonic ocean. Otherwise, without spin off lows, cut off lows, and all the above caveats, it's simply a matter of time before the Atlantic wins out.

GlenH
25 December 2015 22:38:51
Anyway, 18z GFS looking quite different to the 12z GFS (closer to the 12z ECMWF) by 200h....
Quantum
25 December 2015 23:40:25

Is anyone going to comment on the 18Z. 


A mild easterly



2023/2024 Snow days (approx 850hpa temp):
29/11 (-6), 30/11 (-6), 02/12 (-5), 03/12 (-5), 04/12 (-3), 16/01 (-3), 18/01 (-8), 08/02 (-5)

Total: 8 days with snow/sleet falling.

2022/2023 Snow days (approx 850hpa temp):

18/12 (-1), 06/03 (-6), 08/03 (-8), 09/03 (-6), 10/03 (-8), 11/03 (-5), 14/03 (-6)

Total: 7 days with snow/sleet falling.

2021/2022 Snow days (approx 850hpa temp):

26/11 (-5), 27/11 (-7), 28/11 (-6), 02/12 (-6), 06/01 (-5), 07/01 (-6), 06/02 (-5), 19/02 (-5), 24/02 (-7), 30/03 (-7), 31/03 (-8), 01/04 (-8)
Total: 12 days with snow/sleet falling.
Saint Snow
25 December 2015 23:42:19

Anyway, 18z GFS looking quite different to the 12z GFS (closer to the 12z ECMWF) by 200h....

Originally Posted by: GlenH 


 


The 18z doesn't look very good at all to me. Pressure remains stubbornly high over central Europe & energy slips NNE'wards. We end up with a bloody Sceuro High, which is no use to anyone.



Martin
Home: St Helens (26m asl) Work: Manchester (75m asl)
A TWO addict since 14/12/01
"How can wealth persuade poverty to use its political freedom to keep wealth in power? Here lies the whole art of Conservative politics."
Aneurin Bevan
ITSY
25 December 2015 23:46:28

to see out Christmas day, I recommend viewing ptbs 2 and 17 from the GEFS suite  


 


 

Quantum
26 December 2015 00:04:14


 


 


The 18z doesn't look very good at all to me. Pressure remains stubbornly high over central Europe & energy slips NNE'wards. We end up with a bloody Sceuro High, which is no use to anyone.


Originally Posted by: Saint Snow 


Its much better than the 12Z though, we should be pleased to get an upgrade.


 


2023/2024 Snow days (approx 850hpa temp):
29/11 (-6), 30/11 (-6), 02/12 (-5), 03/12 (-5), 04/12 (-3), 16/01 (-3), 18/01 (-8), 08/02 (-5)

Total: 8 days with snow/sleet falling.

2022/2023 Snow days (approx 850hpa temp):

18/12 (-1), 06/03 (-6), 08/03 (-8), 09/03 (-6), 10/03 (-8), 11/03 (-5), 14/03 (-6)

Total: 7 days with snow/sleet falling.

2021/2022 Snow days (approx 850hpa temp):

26/11 (-5), 27/11 (-7), 28/11 (-6), 02/12 (-6), 06/01 (-5), 07/01 (-6), 06/02 (-5), 19/02 (-5), 24/02 (-7), 30/03 (-7), 31/03 (-8), 01/04 (-8)
Total: 12 days with snow/sleet falling.
Retron
26 December 2015 06:37:55


ECM is very snowy. I have drawn the fronts on the 192hr onwards.


Originally Posted by: Quantum 


Actually it was less snowy than the run a couple of days ago - the one I mentioned and comments of "on the sherry" were posted!


At 192 the only areas of significant snow are over the Pennines and Scotland - there are trace amounts over a few other areas, but less than 0.05 of an inch of liquid equivalent.


At 216 there's a little bit of snow over Wales and nothing else south of the Pennines.


By 240 there's more snow over Wales and 0.3 inches of liquid equivalent over the Midlands. Trace amounts are present further south, with (you guesses it) the M4 being the dividing line between sleet and rain.


 


Leysdown, north Kent
Whether Idle
26 December 2015 06:51:55

Lots of options on the table this morning.


 


Here is the GEM Op at 240:


As good as it gets (probably a bit of an outlier!)



Here is GFS @ 240 Weaker, flabbier and poorly positioned for UK cold (ECM may be headed same way)



ECM @ 216 - game over. I imagine this will sit well embedded within the ensemble suite, unlike yesterday's 12z which was part of a tiny cold cluster.



I think the ECM solution is the most likely, but I suppose there's still a chance of things falling into place for us but my view is probably not this time.  Fun model watching all the same.


edit- for the sake of completeness here's the decent UKMO at 144 with a well orientated if slightly too far east high:



Dover, 5m asl. Half a mile from the south coast.
tinybill
26 December 2015 07:23:54
RED rain warning just issued from the Met Office for Lancashire....

http://www.metoffice.gov.uk/public/weather/warnings/#?regionName=nw&from=rss&sn=C517B605-CA85-A903-4665-DD0957DEF6F0_2_NW&tab=warnings&map=Warnings&zoom=7&lon=-3.35&lat=53.77&fcTime=1451088000 


its only going to get worse with a possible hurricane heading our way wednesday
Whether Idle
26 December 2015 08:22:35

Here's the GEM ensemble suite... Op clearly an outlier as the pack are huddled around 0c 850s



Dover, 5m asl. Half a mile from the south coast.
nsrobins
26 December 2015 08:26:49

Feels like the thread is a bit hungover this morning as a sort of reality sinks in - this time it's a probably a near miss.
Folks new to the world of winter model chess will learn that the NWP play an intricate game of kiss and tell, teasing us with seductive glimpses of deep cold and snow one minute only to snatch it away the next. And like the cyclists in a peloton, the leading bunch jostle for position weaving intricate patterns as they play follow the leader and take turns at promoting themselves.

Despite the improvements in accuracy and arreal verification, if you don't see cross-model support for a consistent period and consequetive runs, then you can not claim any particular scenario will occur with any more than say 50% confidence.
Phrases like 'the MetO are on board' are unhelpful if at the same time the desktop PC in Norman, OK has churned out a mildfest GFS operational. Discuss, debate, wonder and marvel yes because this is exactly what this thread is for, but before swapping to winter tyres and checking your antifreeze, there has to be agreement across the board at no greater than +120hrs.

Just an opinion of course


Neil
Fareham, Hampshire 28m ASL (near estuary)
Stormchaser, Member TORRO
Whether Idle
26 December 2015 08:40:05


before swapping to winter tyres and checking your antifreeze, there has to be agreement across the board at no greater than +120hrs.


Originally Posted by: nsrobins 


 I would have thought that anyone taking the time to read the thread would be able to discern that its a thread for discussing model output - therefore what the Models show way into FI will be discussed,(particularly if it shows a divergence from the current record-breakingly mild, dull and flood inducing weather)  it would be surprising to think someone would switch to winter tyres on the basis of an isolated FI model run....


Dover, 5m asl. Half a mile from the south coast.
nsrobins
26 December 2015 08:49:30


 


 I would have thought that anyone taking the time to read the thread would be able to discern that its a thread for discussing model output - therefore what the Models show way into FI will be discussed,(particularly if it shows a divergence from the current record-breakingly mild, dull and flood inducing weather)  it would be surprising to think someone would switch to winter tyres on the basis of an isolated FI model run....


Originally Posted by: Whether Idle 


But they do. And of course all output can be and is discussed and debated. I'm just describing the tactics I employ to avoid getting sucked into the hysteria when a few cold options appear at +300hrs.


As I clearly said, it's just an opinion and you can take it or leave it.


Neil
Fareham, Hampshire 28m ASL (near estuary)
Stormchaser, Member TORRO
marting
26 December 2015 08:49:36
Interesting ECM ensembles this morning with still a good split and this mornings runs being on the warm side of the average.
Martin
Martin
Greasby, Wirral.
haghir22
26 December 2015 08:51:43
Right, I'm cold, soaked, covered in oil and grease but that's the tyres changed.

Oh hold on.....
YNWA
Retron
26 December 2015 08:55:05

Interesting ECM ensembles this morning with still a good split and this mornings runs being on the warm side of the average.
Martin

Originally Posted by: marting 


Here are the ensembles in question. A lot of scatter but always nice to see the odd ice day run in there!



Leysdown, north Kent
Brian Gaze
26 December 2015 09:00:47

Ich bin ein Berliner?



Brian Gaze
Berkhamsted
TWO Buzz - get the latest news and views 
"I'm not socialist, I know that. I don't believe in sharing my money." - Gary Numan
picturesareme
26 December 2015 09:03:26


Feels like the thread is a bit hungover this morning as a sort of reality sinks in - this time it's a probably a near miss.
Folks new to the world of winter model chess will learn that the NWP play an intricate game of kiss and tell, teasing us with seductive glimpses of deep cold and snow one minute only to snatch it away the next. And like the cyclists in a peloton, the leading bunch jostle for position weaving intricate patterns as they play follow the leader and take turns at promoting themselves.

Despite the improvements in accuracy and arreal verification, if you don't see cross-model support for a consistent period and consequetive runs, then you can not claim any particular scenario will occur with any more than say 50% confidence.
Phrases like 'the MetO are on board' are unhelpful if at the same time the desktop PC in Norman, OK has churned out a mildfest GFS operational. Discuss, debate, wonder and marvel yes because this is exactly what this thread is for, but before swapping to winter tyres and checking your antifreeze, there has to be agreement across the board at no greater than +120hrs.

Just an opinion of course


Originally Posted by: nsrobins 


wise words that's I suspect will be met with some degree of hostility by some 😂

Whether Idle
26 December 2015 09:10:51


 


But they do. And of course all output can be and is discussed and debated. I'm just describing the tactics I employ to avoid getting sucked into the hysteria when a few cold options appear at +300hrs.


 


Originally Posted by: nsrobins 


But there has been no hysteria.  There have been charts posted, the odd Christmas Day euphoria comment, its been pretty level headed stuff with discussion.  The flooding situation is now a far more pressing and interesting prospect.


Dover, 5m asl. Half a mile from the south coast.
Brian Gaze
26 December 2015 09:11:07


Feels like the thread is a bit hungover this morning as a sort of reality sinks in - this time it's a probably a near miss.
Folks new to the world of winter model chess will learn that the NWP play an intricate game of kiss and tell, teasing us with seductive glimpses of deep cold and snow one minute only to snatch it away the next. And like the cyclists in a peloton, the leading bunch jostle for position weaving intricate patterns as they play follow the leader and take turns at promoting themselves.

Despite the improvements in accuracy and arreal verification, if you don't see cross-model support for a consistent period and consequetive runs, then you can not claim any particular scenario will occur with any more than say 50% confidence.
Phrases like 'the MetO are on board' are unhelpful if at the same time the desktop PC in Norman, OK has churned out a mildfest GFS operational. Discuss, debate, wonder and marvel yes because this is exactly what this thread is for, but before swapping to winter tyres and checking your antifreeze, there has to be agreement across the board at no greater than +120hrs.

Just an opinion of course


Originally Posted by: nsrobins 


 The improvements in NWP in the last decade are progressive but marginal and I suspect many people don't really understand this.


TBH I think occasionally it is possible to pick a major cold / hot spell at up to about 10 days with a high degree of confidence but you do need cross model agreement. Retron has posted ensemble links in the past and I pay close attention at the 7 - 10 day range because I know this puts you in a good position to get some decent press quotes in, e.g. Dec 2009/10.


Brian Gaze
Berkhamsted
TWO Buzz - get the latest news and views 
"I'm not socialist, I know that. I don't believe in sharing my money." - Gary Numan
Nordic Snowman
26 December 2015 09:13:54


Feels like the thread is a bit hungover this morning as a sort of reality sinks in - this time it's a probably a near miss.
Folks new to the world of winter model chess will learn that the NWP play an intricate game of kiss and tell, teasing us with seductive glimpses of deep cold and snow one minute only to snatch it away the next. And like the cyclists in a peloton, the leading bunch jostle for position weaving intricate patterns as they play follow the leader and take turns at promoting themselves.

Despite the improvements in accuracy and arreal verification, if you don't see cross-model support for a consistent period and consequetive runs, then you can not claim any particular scenario will occur with any more than say 50% confidence.
Phrases like 'the MetO are on board' are unhelpful if at the same time the desktop PC in Norman, OK has churned out a mildfest GFS operational. Discuss, debate, wonder and marvel yes because this is exactly what this thread is for, but before swapping to winter tyres and checking your antifreeze, there has to be agreement across the board at no greater than +120hrs.

Just an opinion of course


Originally Posted by: nsrobins 


Wise words Neil.


I even saw the London/SE Weather FB page last night state that a very cold and snowy picture was set for next weekend! The admin of that page could look like a right tool by this time next week!


Bjorli, Norway

Website 
doctormog
26 December 2015 09:39:59
I'm not sure anyone should be embarrassed at discussing the output shown in a model output discussion thread! The picture is no clearer than it was yesterday or the day before. We know easterlies in the model output are fickle things (if you pardon the anthropomorphism).

We have been down this road many times in the past and yet no one can still say with certainty what will happen. Only time will tell but it will be interesting to see what transpires in the coming weeks. Given current output almost anything is on the table - what we end up dining on remains to be seen but for the sake of those in N England and other flood hit areas I hope it is not "more of the same".
Karl Guille
26 December 2015 09:41:21
Output generally remains the same this morning with High Pressure looking as though it is going to remain a little too far East for our liking early in the New Year with just a chance of something better (as highlighted by the odd Op run or ensemble member as shown over the last three or four days). I see no mass hysteria or winter wonderland posts on this Forum (unlike the past), just some well intentioned comments on the fact that after weeks and weeks of rain for the northern half of the U.K. there is just the chance of something with a more easterly influence as we enter 2016.😉
St. Sampson
Guernsey
David M Porter
26 December 2015 09:46:39

I'm not sure anyone should be embarrassed at discussing the output shown in a model output discussion thread! The picture is no clearer than it was yesterday or the day before. We know easterlies in the model output are fickle things (if you pardon the anthropomorphism).

We have been down this road many times in the past and yet no one can still say with certainty what will happen. Only time will tell but it will be interesting to see what transpires in the coming weeks. Given current output almost anything is on the table - what we end up dining on remains to be seen but for the sake of those in N England and other flood hit areas I hope it is not "more of the same".

Originally Posted by: doctormog 


Good post Michael.


The observation I would make here is that there is at least some more interesting output on offer now than has often been the case since early November. For one thing, the "Euroslug" HP which seems to have been around for an eternity does look like giving ground after next week according to GFS, and ECM up to 240hrs seems to back it up. That in itself would be something of a departure from what we have witnessed for so many weeks now.


Lenzie, Glasgow

"Let us not take ourselves too seriously. None of us has a monopoly on wisdom, and we must always be ready to listen and respect other points of view."- Queen Elizabeth II 1926-2022
Solar Cycles
26 December 2015 10:17:14

I've said for a couple of days that I didn't think we'll get lucky this time around but it's the bigger picture that's important and that continues much the same, block to our east and and the PV under duress. Going into the New Year and we should see further wave activity bashing up the PV and heights to our east remaining strong.

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