theweatheroutlook

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The Beast from the East
04 December 2022 10:44:41
GFS control looks better  than the op so far
"We have some alternative facts for you"
Kelly-Ann Conway - special adviser to the President
doctormog
04 December 2022 10:48:35

GFS control looks better  than the op so far

Originally Posted by: The Beast from the East 



I have noticed that for whatever reason the GFS Control run has been quite consistently cold(er) over the last few days. Perhaps it's not picking up on the pesky little lows due to a lower resolution?
Aberdeen
Current conditions (personal WS) 
The Beast from the East
04 December 2022 10:50:21
Control showing snow for friday night in the SE
Not sure how accurate these charts are though
https://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=138&mode=2&carte=0&ext=0 

 
"We have some alternative facts for you"
Kelly-Ann Conway - special adviser to the President
The Beast from the East
04 December 2022 10:51:22

I have noticed that for whatever reason the GFS Control run has been quite consistently cold(er) over the last few days. Perhaps it's not picking up on the pesky little lows due to a lower resolution?

Originally Posted by: doctormog 


I always assumed the control ran at the same resolution? 
 
"We have some alternative facts for you"
Kelly-Ann Conway - special adviser to the President
Rob K
04 December 2022 10:54:15

Thanks Brian, I can only assume that is a bit of a flaw in that particular model (or I'd be amazed to see the temperature dip to below -20°C!).

Here's the ICON 06z so far and it is conducive to some very low temperatures but not that low I would have thought.

https://www.wetterzentrale.de/maps/ICOOPEU06_114_1.png  

Originally Posted by: doctormog 



I think it does look ripe for -20, given that a lot of models show cold uppers and barely an isobar over the UK at the time in question. Obviously cloud cover will be a major factor. 
Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
ballamar
04 December 2022 11:02:38
The infamous Euro high over France and Spain making its usual appearance a little more now
Rob K
04 December 2022 11:05:35

The infamous Euro high over France and Spain making its usual appearance a little more now

Originally Posted by: ballamar 


Yes I think this ex-hurricane is odds-on to bring a quick return to normal service around mid month. Just when things are looking decently poised Mother Nature has to throw a hurricane at us!
Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
westv
04 December 2022 11:16:54

The infamous Euro high over France and Spain making its usual appearance a little more now

Originally Posted by: ballamar 


You mean the Barttie High? 😀
At least it will be mild!
Heavy Weather 2013
04 December 2022 11:32:47
The GFS 06z ensembles for London are the best yet - pretty much NO scatter up until the 14th.

Beyond that anything is up for grabs, but I would urge caution to anyone saying euro high from mid month. The GFS seems to have a new solution every six hours at the moment.
Mark
Beckton, E London
Less than 500m from the end of London City Airport runway.
doctormog
04 December 2022 11:32:55

I think it does look ripe for -20, given that a lot of models show cold uppers and barely an isobar over the UK at the time in question. Obviously cloud cover will be a major factor. 

Originally Posted by: Rob K 



Perhaps but not in the way that is shown in those charts. In frost hollows with snow cover yes,perhaps Altnaharra or Braemar areas. I may be totally wrong but we will see when the time comes. I think the -11°C as shown in the GFS for that time are more realistic.
Aberdeen
Current conditions (personal WS) 
+1
Gandalf The White
04 December 2022 11:43:03

You mean the Barttie High? 😀

Originally Posted by: westv 



No, because a Bartlett High refers to a recurring pattern, not just the presence of a Euro High.  This is about as far away from a Bartlett as it's possible to get; about Uncle Barrie's fourth cousin three times removed.... 😉

 
Location: South Cambridgeshire
130 metres ASL
52.0N 0.1E


+2
David M Porter
04 December 2022 11:50:16

The GFS 06z ensembles for London are the best yet - pretty much NO scatter up until the 14th.

Beyond that anything is up for grabs, but I would urge caution to anyone saying euro high from mid month. The GFS seems to have a new solution every six hours at the moment.

Originally Posted by: Heavy Weather 2013 



Indeed, Mark.

I have seen people say in the past that whenever the models have to deal with ex-hurricanes and ex-tropical storms, consistency goes out of ht window for a while at least. I think we are probably seeing another example of that 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
Gandalf The White
04 December 2022 11:52:19

The GFS 06z ensembles for London are the best yet - pretty much NO scatter up until the 14th.

Beyond that anything is up for grabs, but I would urge caution to anyone saying euro high from mid month. The GFS seems to have a new solution every six hours at the moment.

Originally Posted by: Heavy Weather 2013 



Yes, based on the opening data, the current evolution looks broadly consistent.  But we get suckered in every year by the ensemble analysis: it won't pick up an unexpected change in the state of the atmosphere or unexpected interactions: we have all seen the op and it's ensemble suite flip.

As others have said, it looks increasingly messy and difficult to predict beyond the up coming very cold spell which will arrive around Tuesday into Wednesday (north to south) and run through the weekend. For me the risks to an early breakdown of the cold pattern are the block retrogressing too far west and that energy to the south-west, but they're only risks at this stage.

In cold, dry Arctic Maritime flows inland areas and the south particularly are always likely to see clear blue skies: for me that's one of the appeals of such weather, as we approach the winter solstice where sunlight is at a premium.  Disturbances and polar lows (remember them?) are only ever going to appear on the high res, short range output.
Location: South Cambridgeshire
130 metres ASL
52.0N 0.1E


Brian Gaze
04 December 2022 11:54:59

Yes I think this ex-hurricane is odds-on to bring a quick return to normal service around mid month. Just when things are looking decently poised Mother Nature has to throw a hurricane at us!

Originally Posted by: Rob K 



It will be interesting to see whether this IS our winter (as the seasonal models mostly suggest) or just an amuse-bouche. 
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
Snowedin3
04 December 2022 12:54:55
I never get the constant look for the breakdown,  at the moment we're looking at a 5-7 day cold spell with snow opportunities, and we all know snow is hard to forecast this far out!
Dean Barnes
Finstock, Chipping Norton, Oxfordshire
160m ASL 525 Ft
The Beast from the East
04 December 2022 12:59:19

I never get the constant look for the breakdown,  at the moment we're looking at a 5-7 day cold spell with snow opportunities, and we all know snow is hard to forecast this far out!

Originally Posted by: Snowedin3 


Yes, though with access to so much data its always easy to look too far ahead. In the olden days of teletext and Countryfile weekly forecast, we were much happier!
Anyway, enjoy the coming week as it could be the only winter we have this year as Brian suggested. 
Lets hope there are no power cuts!
 
"We have some alternative facts for you"
Kelly-Ann Conway - special adviser to the President
CField
04 December 2022 13:15:19
Been some great posts on here....January 85 springs to mind on possible similar weather set ups without the frigid uppers but it isn't January yet...the current theme could be recurring and  deliver a classic snowy winter to NW Europe....we are well overdue  a severe winter....1917 was a Dec to April winter can't think of too many that go the distance maybe 22/23?
Favourite snowstorm
Famous channel low
Dec 31st 1978
Hastings East Sussex
Foot of level snow severe drifting
Next day max temp -4 degrees Celsius
some faraway beach
04 December 2022 14:05:20
Another reminder of how odd the synoptics are right now. I can't recall the analogue index ever being such a high number, ever since Brian first began publishing it. We're in uncharted territory here.

04 DEC 2022
Place Year Index value
1       1995 12619
2       1978 12784

Having said that, December 1995 or, in particular, Dec. 1978, would do very nicely, thank you.
 
2 miles west of Taunton, 32 m asl, where "milder air moving in from the west" becomes SNOWMAGEDDON.
Well, two or three times a decade it does, anyway.
Jiries
04 December 2022 14:07:01

Yes, though with access to so much data its always easy to look too far ahead. In the olden days of teletext and Countryfile weekly forecast, we were much happier!
Anyway, enjoy the coming week as it could be the only winter we have this year as Brian suggested. 
Lets hope there are no power cuts!
 

Originally Posted by: The Beast from the East 



That what i miss the old days and any model suggesting this only winter we will get need to be scrapped, don't believe any long range nonsense,  Did they forecast 40C on 19th July 2022 from the long range forecast aerlier this year for summer 2022? 
Rob K
04 December 2022 14:22:16

Perhaps but not in the way that is shown in those charts. In frost hollows with snow cover yes,perhaps Altnaharra or Braemar areas. I may be totally wrong but we will see when the time comes. I think the -11°C as shown in the GFS for that time are more realistic.

Originally Posted by: doctormog 


Met Office automated forecast only goes for -5C at Altnaharra. 
Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
Rob K
04 December 2022 14:28:14
Here's a vaguely model related question. If you look back at reanalyses charts for a lot of classic snow events you see very underwhelming 850mb temperatures, often only -5 or -6. Yet these days even when 850s are -7 or -8 or even lower we seem to overwhelmingly get rain. 

I know there is a lot more to it than 850mb temperatures but is there a reason for this? Has the boundary layer of air really warmed that much in the last few decades?
Yateley, NE Hampshire, 73m asl
"But who wants to be foretold the weather? It is bad enough when it comes, without our having the misery of knowing about it beforehand." — Jerome K. Jerome
doctormog
04 December 2022 14:31:01

Met Office automated forecast only goes for -5C at Altnaharra. 

Originally Posted by: Rob K 



Yes, I'm not sure any of the automated forecast locations are showing anything like that model's output.

I think Deeside or Speyside (perhaps around Glenlivet) may be a better call for the lowest temperatures if there is any wind further north. Given the significant changes in detail at this range I guess it's all rather hypothetical anyway. Will it all change again on the 12z output?
Aberdeen
Current conditions (personal WS) 
Essan
04 December 2022 14:53:54

Met Office automated forecast only goes for -5C at Altnaharra. 

Originally Posted by: Rob K 



Same as it showing for down here .....   I think it should be a tad cooler in Sutherland!
Andy
Evesham, Worcs, Albion - 35m asl
Weather & Earth Science News 

Anyone who is capable of getting themselves made President should on no account be allowed to do the job - DNA
fairweather
04 December 2022 15:02:46

The concept is that the algorithm is not dealing with the input parameters in an appropriate way. The extremely localised nature of the very low minima suggest a direct and possibly flawed correlation between snow depth and 2m temperature to me. I would expect this may be an issue that will be tweaked in future. I'm surprised you don't think a model could be overdoing temperature extremes based on flaws in an algorithm.

In this case we are not dealing with any random perturbation, rather the operational run. If, since the last update/version, the model has not encountered such synoptics as shown it is perfectly valid to assume the model may be "overdoing it".

Originally Posted by: doctormog 


Yes, I don't disagree with you directly, maybe the term "over doing it" is a bit misleading for the less technical. What I don't personally understand is why would the model, with all the experts employed, have a flawed algorithm? I think there are different algorithms and data perhaps for different pets which could explain temperature extremes but these are just varying percentiles of probablity rather than "flaws" in the model per say. 
S.Essex, 42m ASL
fairweather
04 December 2022 15:10:13

Here's a vaguely model related question. If you look back at reanalyses charts for a lot of classic snow events you see very underwhelming 850mb temperatures, often only -5 or -6. Yet these days even when 850s are -7 or -8 or even lower we seem to overwhelmingly get rain. 

I know there is a lot more to it than 850mb temperatures but is there a reason for this? Has the boundary layer of air really warmed that much in the last few decades?

Originally Posted by: Rob K 


I'm not sure either. If the boundary layer had warmed wouldn't that just show as higher 850 hPa? Don't know. But I was under the impression that the temp at the 850mb height is absolute. i.e -7C then is the same as -7C now. Could it be the effect of AGW at the nearer surface level, i.e  ground and SST's being a couple of degrees higher  due to later summers, milder autumns and few if any pre-Christmas frosts? I really don't know but agree with your perception.
S.Essex, 42m ASL

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