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Fothergill
21 December 2014 10:23:01


This is very different to most other models are showing but just highlights that at this point the pattern beyond the storm predicted for 27/28 Dec is pure speculation. Anything is possible.


Originally Posted by: Global Warming 


Well of course - all forecasting is speculation. But, balance of probabilities is all we can work on.


Monster storm on the GFSP. Loads of persistent heavy rain which looks likely to cause flooding. A lot wintry/snow showers following in behind too! GFS less extreme.




 

Hippydave
21 December 2014 10:23:56

GFS is obviously firming up on no Greenland blocking (mid to longer term) although it's not a warm run and would probably result in some chilly weather, snow generally confined to favoured spots of the North.


Before it gets 'washed' away by the 6z P3 is quite nice and continues to fly the Greenie HP flag, bringing cold unstable air to the UK.


The ECM op isn't too far away from GFS, although would need to see where it sits within the ens to comment further.


 


Being vaguely optimistic I'd be surprised if the models don't toy with a flatter pattern for a few days before picking up a new colder signal - there's plenty of attempts at ridging North, HP over Scandi etc in the ens still.


Home: Tunbridge Wells
Work: Tonbridge
21 December 2014 10:24:04

GFS 6z has the deep low next weekend much further south again. 38mb drop in pressure in just 24 hours. If it were to take this track it would cause major disruption.


http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/126-515UK.GIF?21-6
http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/132-515UK.GIF?21-6
http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/138-515UK.GIF?21-6
http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/144-515UK.GIF?21-6
http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/150-515UK.GIF?21-6


At T150 wind gusts even inland in the far south east could exceed 120kph (that is 75mph)


http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/150-289UK.GIF?21-6


GFS(P) sticks with a more northerly track but still explosive cyclogenesis (34mb in just 12 hours!) and then has the low sink back south again down the east coast 


http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/132-515PUK.GIF?21-6
http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/138-515PUK.GIF?21-6
http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/144-515PUK.GIF?21-6
http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/150-515PUK.GIF?21-6
http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/156-515PUK.GIF?21-6


Wind gusts on this track peak in the western isles at more than 140kph (87 mph)


http://modeles2.meteociel.fr/modeles_gfs/runs/2014122106/156-289PUK.GIF?21-6


Some places are likely to get a real battering next weekend. It will take several more days to firm up on exactly where.

The Beast from the East
21 December 2014 10:28:40

http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfs-0-180.png?6


Bit of a "Murr Sausage". The best we can hope for considering the polar profile


"We have some alternative facts for you"
Kelly-Ann Conway - special adviser to the President
The Beast from the East
21 December 2014 10:29:41

http://www.wetterzentrale.de/pics/Rtavn18017.gif


A cold day


"We have some alternative facts for you"
Kelly-Ann Conway - special adviser to the President
Gooner
21 December 2014 10:31:18

http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsnh-0-186.png?6


Not that far from producing an Easterly


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


roger63
21 December 2014 10:31:30


Morning model watchers.


I took a break from model watching last night, had an early night, got 8 hours of sleep and have come back with a fresh pair of eyes.


As it was really, certainly up to the early part of Boxing day with mild air in the south being swept away from the south on Christmas Eve ahead of a bright and chilly couple of days with the risk of a few wintry showers in the north east. Aberdeen looks favoured at the moment for the odd flurry on the big day Doc. 


The rapidly deepening depression on the night of the 26/27th is becoming generally well modelled with the exception of the ECM. The GEFS continue to pick this up well.


No chart available for the selected hour. Many charts start at 3 hours ahead, so if you have 0 hours selected try stepping forward or selecting a later hour.


In the wake of the depression there is the potential for some cold air, at least temporarily, in its wake with the risk of snow showers for exposed eastern and coastal locations and possibly more generally if the feature develops a wrap around occlusion or the track is further south.


Thereafter high pressure appears to settle close to the UK bringing us into a calm frosty period in a week's time, what happens to the high pressure thereafter is very much FI. The form horse would be for it to slowly ebb into Europe restoring the PV to Greenland restoring the recent pattern, however, there are some weak signals for an attempted ridge to Scandinavia, hence increasing the longevity of the colder spell into New Year.


Lots to watch..especially that potential nasty storm.


Have a good day.  


 


Originally Posted by: Gusty 


Agree with your point that there are some weak signals in FI for an attempted ridge to Scandinavia.In my view that represents the best chance of  a proper cold spell developing.I shall be watching the ENS to see if there is growing support for this.Otherwise w eare i fera stuck with either a strong WSW flow or at best  LP's moving SE followed by transitory ridges.

Gooner
21 December 2014 10:35:34

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2014/12/21/basis06/ukuk/rart/14122706_2_2106.gif


Blizzards over some Northern areas


http://expert-images.weatheronline.co.uk/daten/proficharts/en/2014/12/21/basis06/ukuk/rart/14122712_2_2106.gif


Snow over many Northern areas as well as parts of Wales


http://expert-images.weatheronline.co.uk/daten/proficharts/en/2014/12/21/basis06/ukuk/rart/14122718_2_2106.gif


Snow for the South on the back edge as the LP moves away


 


J F  F  of course


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Phil G
21 December 2014 10:35:38
Very interesting run from GFS.
The storm moves away from the SE but is now being modelled as more of a feature as it moves into the Med. This leads to more opportunities from the north or the east still to be determined.
Whether Idle
21 December 2014 10:38:29


http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsnh-0-186.png?6


Not that far from producing an Easterly


Originally Posted by: Gooner 


That must be the sort of run that the ECM ens are producing (not the op).  The 12z GFS Op and 12z GEFS will be of interest and of course the ECM 12z. 


Dover, 5m asl. Half a mile from the south coast.
Gooner
21 December 2014 10:40:23

http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsnh-0-216.png?6


Very interesting from GFS, GFSP had been hinting at Easterly it seems GFS is also toying with the idea


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Gooner
21 December 2014 10:41:39


 


That must be the sort of run that the ECM ens are producing (not the op).  The 12z GFS Op and 12z GEFS will be of interest and of course the ECM 12z. 


Originally Posted by: Whether Idle 


At the back end of last week GFSP was looking at the idea.


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Gooner
21 December 2014 10:43:48

http://www.wetterzentrale.de/pics/Rtavn2401.gif


Blocking in the above could be enough to have a winner from the East


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Whether Idle
21 December 2014 10:44:52


http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsnh-0-216.png?6


Very interesting from GFS, GFSP had been hinting at Easterly it seems GFS is also toying with the idea


Originally Posted by: Gooner 


Yep.  The best that can be said is that it wouldn't take a lot of adjustment for that to be very interesting by the standards of the last 2 winters.


When we get stellar charts at this range they always get downgraded, a few gentle up grades from here is the best possible outcome.  The other, perhaps more likely option, is for the high to sink south and the westerly flow to take over as the PV settles in over its Greenlandic spiritual home.  Interesting times.


Dover, 5m asl. Half a mile from the south coast.
Gooner
21 December 2014 10:46:10

http://www.wetterzentrale.de/pics/Rtavn20417.gif


http://www.wetterzentrale.de/pics/Rtavn22817.gif


http://www.wetterzentrale.de/pics/Rtavn25217.gif


A cold end to year for most of the UK ...............according to GFS 6z


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


idj20
21 December 2014 10:46:53

Ouch, as the lastest GFS run brings the belly of the beast right close to the south east on the 27th, thus making it an awful day for travelling across the whole of England and Wales, horrible timing what with everyone planning on getting home after spending Christmas with relative/friends/families.



It might even bring some back-end snow over high ground as the low pulls away into the near continent, but by this point the 850 hPas doesn't really look that favourable for it - unless the system really has the effect of rapidly pulling down cold air from much higher up and has the effect of quickly turning the rain into as snow for a short time before the lot clear away and high pressure quickly builds over (would lead to a couple of very frosty nights!).
 
However, on this occasion, the primary concern is strong wind and the threat of a tidal surge along the East Coast - but this is only one of many runs so I'll give it a few more goes and see what it all looks like tomorrow.

PS: GFS's baby brother, GFSP, wants to take the centre of the low pressure on a more traditional track (skimming eastwards along north Scotland) - and then suddenly diving southwards which looks a bit "weird" to my eyes, so it shows that there are still much uncertainly in terms of timings, intensity and tracking - but one thing for certain is that we will have to go through a short spell of very unsettled weather post-Christmas before things appear to calm down again in time for the New Year.


Folkestone Harbour. 
tallyho_83
21 December 2014 10:48:10

A potential easterly into the New Year?!?



Home Location - Kellands Lane, Okehampton, Devon (200m ASL)
---------------------------------------
Sean Moon
Magical Moon
www.magical-moon.com


Stormchaser
21 December 2014 10:48:29

The main loss this morning is not so much a good bit of Greenland Blocking (absent from the ECM op and ECM ensembles for a few days now) but the southern arm of the jet cutting under the mid-Atlantic ridge to sustain it to our W/NW, which was being strongly suggested by ECM and its ensembles on yesterdays 12z suite.


As I inferred yesterday, it seemed GEFS was more likely to back down based on history and background drivers, yet the opposite has occurred this morning.


This seems to be down to a shortwave low reaching Newfoundland on day 6 and then being steered over the ridge rather than to the south of it. Another case of bad fortune it would seem!


 


So with that option out of the window for now at least, the focus is well and truly on the potentially dangerous storm system 27th-28th December.


This morning sees close agreement among ECM, GFSP, UKMO and GFS for this system to be generated from the collision of two shortwaves, one from the NW and one from the SW, in 6 days time.


However ECM continues to show this happening further NW than the other models, and this looks to be due to the ridge across the UK on Boxing Day being stronger and extending further north i.e. a more amplified solution. After it's poor show recently, this is starting to seem a bit suspect if you ask me.


 


We do still see a bit of a SE movement by the trough on the ECM run and there lies another major source of uncertainty - to what extent will the low drop south or southeast, and could it even manage to drop into Europe prior to the flattening of the upstream pattern?


Just getting low heights down toward the Med. could come in handy if the upstream pattern holds on to enough amplification, as the GFSP 00z suggested.


ECM was too far NW with the initial trough development, didn't really try to sink the trough until it was too far east for us, and too vigorous with the flattening of the Atlantic pattern, so basically the worst of all worlds. It appears that the first two are probably cause and consequence, while the third was the result of a shortwave low bombing out over Newfoundland on day 9. Cheers, ECM... *sarcasm alert*


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
Gooner
21 December 2014 10:49:33

http://www.wetterzentrale.de/pics/Rtavn2641.gif


A decent block to the East , certainly NO zonal train on this run


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


21 December 2014 10:49:51

The model watching is really quite fascinating at the moment. I am more focused on interesting weather rather than cold weather per se and there are certainly plenty of interesting things going on right now.


As well as the potential for rapid cyclogenesis over the UK next weekend there is also a similar but somewhat less dramatic event taking place over the north eastern side of the US and Canada a couple of days earlier. This is important because it impacts heavily on what happens to the pressure pattern over Greenland.


This first chart shows the position at 12z on Christmas Eve and looks quite benign. What you need to look for is the low with a centre just under 1000mb centred on the Kentucky / Tennessee border.


http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsna-0-78.png?6


12 hours later the low has drifted north to the US / Canadian border near Detroit and is now at 995mb


http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsna-0-90.png?6


The low keeps moving NNE and deepening


http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsna-0-102.png?6
http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsna-0-114.png?6
http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsna-0-126.png?6


By 18z Boxing Day it reaches the north coast of Canada at 955mb


http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsna-0-132.png?6


Switching to the wider view at the same time (18z Boxing Day) we see pressure of 1045mb over Greenland


http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfs-0-132.png?6


18 hours later that high pressure over Greenland has been entirely eroded. This seems perfectly plausible given the strength of the storm that has developed over Canada.


http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfs-0-150.png?6

colin46
21 December 2014 10:51:16


http://modeles.meteociel.fr/modeles/gfs/runs/2014122106/gfsnh-0-216.png?6


Very interesting from GFS, GFSP had been hinting at Easterly it seems GFS is also toying with the idea


Originally Posted by: Gooner 

westerly it is then!


shine on you crazy diamond
192.104 m / 630.262 feet ASL
Rob K
21 December 2014 10:53:09


http://www.wetterzentrale.de/pics/Rtavn2641.gif


A decent block to the East , certainly NO zonal train on this run


Originally Posted by: Gooner 


But just look at those purples to the north. Absolutely zero sign of any northern blocking now on GFS. A massive step backwards for any cold spell over the past couple of days. 


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
Gooner
21 December 2014 10:58:37

I'd be very happy with that run, not a snowfest by any stretch but some low temps and very seasonal


Remember anything after T120 is really Just For Fun



Marcus
Banbury
North Oxfordshire
378 feet A S L


Andy Woodcock
21 December 2014 10:59:41
II really do not think the new year period is set in stone as zonal, models are still all over the place and who can blame them with this monster UK low likely to shack the troposphere up in a weeks time.

I say let's get to the storm and see what the models produce after that, it could look very different by then.

What I am not looking forward to are those severe gales which believe me will be wet not white across the bulk of the UK, the Synoptics are very similar to the Great Highland Blizzard of 28th January 1978 when most lowland places had rain or at best sleet. By the time low uppers sweep south it will be too dry.

Another above average CET month is pretty certain now leading to record warmth in 2014, combine that with an end of year storm and we will hear lots about global warming, severe weather etc, that will drive me nuts so I am not looking forward to that either!

I wonder if it's too late to get a flight to Lanzarote next week
Andy
Andy Woodcock
Penrith
Cumbria

Altitude 535 feet

"Why are the British so worried about climate change? Any change to their climate can only be an improvement" John Daley 2001
Retron
21 December 2014 11:03:13


A massive step backwards for any cold spell over the past couple of days. 


Originally Posted by: Rob K 


I disagree.


EPS ensembles have been consistently showing a cold spell post-Christmas over the past few days and all that's happened is we now have one normal day after Christmas (and Boxing Day), temperature wise: beyond that the clustering suggests colder-than-average temperatures. Yes, there's a chance that mild conditions will set in but it is, and has been, a low chance over the past few days.


GFS finally throws out a run resembling those of the cold cluster and GFS(P) isn't exactly mild either.


Or, in other words, very little has actually changed over the past few days. The most likely option remains a cold spell after Christmas, the only uncertainties are regarding that low (track, intensity) and whether it'll be cold enough for snow down here once it clears!


Leysdown, north Kent

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