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David M Porter
17 December 2014 17:19:56

Seems that changes to some colder weather may be afoot later next week, will they come to fruition


Take it away folks.


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
Rob K
17 December 2014 17:31:48
http://www.wetterzentrale.de/pics/Rgem1801.gif 

http://www.wetterzentrale.de/pics/Rgem2281.gif 
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
Polar Low
17 December 2014 17:40:34

really?? or have I had to many jd,s


control


Stormchaser
17 December 2014 17:41:40

So... GFS is about the same as many recent runs have been for Christmas Day while GFSP manages to find improved alignment to the high pressure in the mid-Atlantic and also drops the shortwave development to the NW.


GFS suddenly starts to push energy east from out west of the Azores as soon as it hits lower-res at +192 hours... suspicious behaviour yet that only serves to produce something not far from the ECM 00z for 27th December (a quite violent storm for the south but with a track that limits snow to an unstable, disturbance-laden northerly overnight and through 28th December... yes even this rocky road bears fruit!). After that comes a raging jet under a strong Greenland High... not a logical coupling at all! That aspect of the run is best ignored really.


GFSP once again completely walls off the Atlantic right until the end of 2014. As the NW Europe trough sinks into the Med. there's a lot of fun and games to be had and even at the end of the run it's easy to see how HP over Scandinavia could have provided stronger resistance (sounds greedy but I'm just saying!).


 


Still best to regard GFSP as the best case scenario on offer for prolonged cold, with the shut-down Atlantic jet yet to feature on an ECM operational run. Given it's upgraded nature this will be an interesting test and could set the benchmark by which we judge such promising output in future situations.


As for runs like the GFS 00z, GFS 12z and ECM 00z, Sure, having lows tracking close to the Channel and engaging the cold air would hold huge snowfall potential, but it's a more dangerous game by far. Are you a gambling fellow? foot-in-mouth


 


I'll aim to have some nice charts posted once we have ECM's view in the mix 


If you have any problems or queries relating to TWO you can Email [email protected]

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2023's Homeland Extremes:
T-Max: 30.2°C 9th Sep (...!) | T-Min: -7.1°C 22nd & 23rd Jan | Wettest Day: 25.9mm 2nd Nov | Ice Days: 1 (2nd Dec -1.3°C in freezing fog)
Keep Calm and Forecast On
Polar Low
17 December 2014 17:50:11

Adjustment is usually south James that would be game on midlands north perhaps further south of course Matty would get the luck he always does.


But we have a long way to go 



 


 


 



So... GFS is about the same as many recent runs have been for Christmas Day while GFSP manages to find improved alignment to the high pressure in the mid-Atlantic and also drops the shortwave development to the NW.


GFS suddenly starts to push energy east from out west of the Azores as soon as it hits lower-res at +192 hours... suspicious behaviour yet that only serves to produce something not far from the ECM 00z for 27th December (a quite violent storm for the south but with a track that limits snow to an unstable, disturbance-laden northerly overnight and through 28th December... yes even this rocky road bears fruit!). After that comes a raging jet under a strong Greenland High... not a logical coupling at all! That aspect of the run is best ignored really.


GFSP once again completely walls off the Atlantic right until the end of 2014. As the NW Europe trough sinks into the Med. there's a lot of fun and games to be had and even at the end of the run it's easy to see how HP over Scandinavia could have provided stronger resistance (sounds greedy but I'm just saying!).


 


Still best to regard GFSP as the best case scenario on offer for prolonged cold, with the shut-down Atlantic jet yet to feature on an ECM operational run. Given it's upgraded nature this will be an interesting test and could set the benchmark by which we judge such promising output in future situations.


As for runs like the GFS 00z, GFS 12z and ECM 00z, Sure, having lows tracking close to the Channel and engaging the cold air would hold huge snowfall potential, but it's a more dangerous game by far. Are you a gambling fellow? foot-in-mouth


 


I'll aim to have some nice charts posted once we have ECM's view in the mix 


Originally Posted by: Stormchaser 

Quantum
17 December 2014 18:08:02

Brian is something wrong with the parallel? I'm still only up to 99hrs?!


 


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.
Polar Low
17 December 2014 18:11:28

 


http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=234&mode=0&runpara=1&carte=1


 


 



Brian is something wrong with the parallel? I'm still only up to 99hrs?!


 


Originally Posted by: Quantum 

Quantum
17 December 2014 18:19:53


It turned out I was downloading from the wrong server I confused the parallel for the low res GFS 


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.
Hippydave
17 December 2014 18:21:16

Hmmm, some nice ens members from the 12z GFS but cold still in the minority.


Would be nice to see a solid and growing clump picking out the same colder solution but run to run we just get scatter.


I'm guessing at least some of this is how the LPs exit Canada/North America - if they're held up and we get some decent stable WAA up the Western flank of Greenland it all ends up promising. If the Low Pressure doesn't play ball we end up in a messy zonal picture, although with cold air around it's quite possible someone will get an impressive if temporary snow event. (For high ground in Scotland suspect it'd be not temporary!)


One interesting thing in the outer reaches of FI is even the zonal members try to build Northern blocking, hinting that if attempt 1 fails then attempt 2 is waiting in the wings


Will be interesting seeing the ECM op run - may be one of those high res situations where the ens won't fall in line until late on, or it may just be a weak blocking signal is being played with, only to be dropped in a couple of days time


I'm very much in the glass half-empty camp at present


Home: Tunbridge Wells
Work: Tonbridge
idj20
17 December 2014 18:37:42

GFSP model - Thaaaaaaaaaaaaat's better. Much better.

The old skool FGS model - Pfff.

What is the mighty ECM going to make of it? I'll find out in about half an hour (although I do use weatheronline to view it as I'm so used to the layout).

Of course, the bits I wanted to see in the new GFS are all in low res and it will all look completely different in the next run, but, I do like a good ending to a sci fi story.

Oh my. I really am becoming a Model Output monster.


Folkestone Harbour. 
Gooner
17 December 2014 18:42:05

http://modeles.meteociel.fr/modeles/gfs/runs/2014121712/gfsnh-0-162.png?12 GFS at 162


http://www.meteociel.fr/modeles/ecmwf/runs/2014121712/ECH1-168.GIF?17-0  ECM at 168


Not that far off each other IMO


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Gooner
17 December 2014 18:44:43

http://www.meteociel.fr/modeles/ecmwf/runs/2014121712/ECH1-192.GIF?17-0 ECM 192


http://modeles.meteociel.fr/modeles/gfs/runs/2014121712/gfsnh-0-192.png?12  GFS 192


 


Not a million miles from each other


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Quantum
17 December 2014 18:53:08

Big upgrade on the ECM, its on now! 


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.
Brian Gaze
17 December 2014 18:55:16


Brian is something wrong with the parallel? I'm still only up to 99hrs?!


 


Originally Posted by: Quantum 


The GFSP12 has available on TWO for a couple of hours:


http://www.theweatheroutlook.com/twodata/datmdlout.aspx


Are you still having probs viewing it?


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
Gooner
17 December 2014 18:57:14

http://www.meteociel.fr/modeles/ecmwf/runs/2014121712/ECH1-240.GIF?17-0


Gets there in the end...................cant complain really about todays runs


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Brian Gaze
17 December 2014 18:59:53

The GEFS look ok for a cold snap but nothing too exciting. I've seen comments on Twitter saying otherwise so feel free to disagree.  



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
Polar Low
17 December 2014 19:03:31

looks colder than it looks under the spotlight for the big day mild xmas i think not at this stage.



 


[quote=Gooner;6522


http://www.meteociel.fr/modeles/ecmwf/runs/2014121712/ECH1-192.GIF?17-0 ECM 192


http://modeles.meteociel.fr/modeles/gfs/runs/2014121712/gfsnh-0-192.png?12  GFS 192


 


Not a million miles from each other


Quantum
17 December 2014 19:05:06


 


The GFSP12 has available on TWO for a couple of hours:


http://www.theweatheroutlook.com/twodata/datmdlout.aspx


Are you still having probs viewing it?


Originally Posted by: Brian Gaze 


I downloaded from 2p5 rather than 0p25; I'm still getting used to it so still making these schoolboy mistakes (I'm using the same script for all my GFS and GFSP charts, at some-point I'll get round to adding a parameter that changes the model) Seems to work fine now. 



Boxing day clearly a dream for western areas. Also I remember a trough like that thing to the east hitting in 2010 and dumping about a foot of snow, this is just a taster though, but I'm sure the short term forecasting will be fun when we get in that range!


On a final (and slightly off topic note) do you think there would be any interest on TWO for a GRaDs thread to share scripts and tips, that sort of thing? I know retron uses it and you use it too. 


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.
Brian Gaze
17 December 2014 19:08:23


On a final (and slightly off topic note) do you think there would be any interest on TWO for a GRaDs thread to share scripts and tips, that sort of thing? I know retron uses it and you use it too. 


Originally Posted by: Quantum 


I'd sooner discuss privately with you (and others) rather than on the forum. 


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
bledur
17 December 2014 19:08:48

Temperatures on the downward path after Christmas eve,


Slideshow image

Brian Gaze
17 December 2014 19:13:00

12z ECM looks poor to me. I know different sites use different projections and it can be deceptive, but the uppers and thickness values for southern and central regions suggest rain not snow. A more interesting picture in Scotland. 



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
Arbroath 1320
17 December 2014 19:15:03


http://www.meteociel.fr/modeles/ecmwf/runs/2014121712/ECH1-240.GIF?17-0


Gets there in the end...................cant complain really about todays runs


Originally Posted by: Gooner 


Actually, that is a very good chart when you look at the progression from the former at 216h. The 240h has a strengthening Greeny High giving a stable mid-Atlantic block and lows to our SW tracking to the South of the UK. That screams of prolonged cold spell to me. Certainly no quick breakdown from there.


GGTTH
David M Porter
17 December 2014 19:18:16


Big upgrade on the ECM, its on now! 


Originally Posted by: Quantum 


I'll say this Quantum: Tonight's charts are far better than anything we saw in the reliable timeframe at any stage last winter!


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
Brian Gaze
17 December 2014 19:19:00


 


Actually, that is a very good chart when you look at the progression from the former at 216h. The 240h has a strengthening Greeny High giving a stable mid-Atlantic block and lows to our SW tracking to the South of the UK. That screams of prolonged cold spell to me. Certainly no quick breakdown from there.


Originally Posted by: Arbroath 1320 


Not at all convinced looking at the 216 - 240 evolution. 


 


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
Rob K
17 December 2014 19:19:26


 


Actually, that is a very good chart when you look at the progression from the former at 216h. The 240h has a strengthening Greeny High giving a stable mid-Atlantic block and lows to our SW tracking to the South of the UK. That screams of prolonged cold spell to me. Certainly no quick breakdown from there.


Originally Posted by: Arbroath 1320 


 


Yes, at 240 it is not good for snow for most but I think it would evolve quite nicely looking at the strength of the Greenland blocking.


 


Meanwhile the GFS 12Z ensembles show some good clustering for an earlier, but shorter cold spell. All options still open.


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

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