Oh pupil of Nienna, servant of Manwe, it won't be the first time.

06Z GFS - Meh
PS: Congrats on 14K posts.

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♪♪ I'm dreaming of a _hite Christmasssss... ♪♪

http://www.wetterzentrale.de/pics/Rtavn3484.png 

http://www.wetterzentrale.de/pics/Rtavn3481.png 


I'll have an S please Bob...

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That almost resembles January 1984.

 

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I would agree with this. The ECM ens have been pretty consistent with progging the overall broader pattern change, though I have noticed in the last couple of days a variation in actual MSLP intensity from run to run. This morning's output for example have lower values over NW Europe as a whole from 168hrs onwards than what was shown last night, which had values nearer to normal or above.

In any case, I for one am happy that the weather is forecast to stir up a bit. 

http://www.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/eps/ensm/essential!Geopotential%20at%20500hPa!Europe!192!pop!od!enfo!plot_ensm_essential!2013121100!!chart.gif

 

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Might or might not be of interest to you guys but a potential SSW event being discussed here - http://forum.weatherzone.com.au/ubbthreads.php/topics/1188254/4/Stratospheric_sudden_warmings_

 

Not an expert on these by any means but something to keep an eye on perhaps.

Which if I recall correctly was very boisterous with gales and a cold zonal flow.
For the record Feb 84 was pretty blocked but not too cold anywhere.

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Cold zonality? I think the lows would need to dig further south to bring anything wintry even to Scotland.

 

Actually it's pretty amazing how much cold air is over America at the moment. The -10C isotherm isn't even all that far away directly to our west. If the Atlantic was half as wide then we'd enjoy some very different weather!

http://www.wetterzentrale.de/pics/Rtavn902.png

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Breezy...  a good time to stay indoor, eating, drinking and watching Dr Who on the telly.

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Or this 

http://www.wetterzentrale.de/pics/archive/ra/1999/Rrea00119991225.gif

That one I remember for having to get out of the car to clear several large branches out of the road on Xmas day morning on a trip to the in-laws.

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Yes, been there....  But in 'another place'....

06z - agreed, but you can add most of the recent runs by most of the models to that.... You know it's not great when even a slight air frost is hard to find.

Re-14k posts, thanks Neil, I didn't even notice.  Definitely too much time spent here....

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When the ensemble mean chart shows the main low pressure SW of Iceland and a high pressure cell 1,000 miles south of Newfoundland you know there's only one outcome.

ECM 00z: http://www.meteociel.fr/modeles/ecmwf/runs/2013121100/EDH1-240.GIF?11-12

GFS 06z: http://modeles.meteociel.fr/modeles/gens/run/gensnh-21-1-240.png?6

 

But if you're looking for a glimmer of hope, the GEM ensemble puts the core of the LP over northern Scandinavia:

http://modeles.meteociel.fr/modeles/gens/gem/run/gensnh-21-1-240.png

Which drives the colder air much further south:

http://modeles.meteociel.fr/modeles/gens/gem/run/gensnh-21-0-240.png

 

 

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Not much that can be said at the moment. Lets hope January brings us a reward for all our patience

 

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This Morning GFS, UKMO charts Show Large N NW and NE wards from Mid N Atlantic up through the NE as well, Large Complex PV with Some Short Waves associated with.

Some Waving activity in it means the UK will for the next 15 days at least be Unsettled with both spells of less cold, and also some Colder NW flow's.

We also expect some SW winds and there are some featured High Ridges of the Charts.

10hPa Stratospheric Warming is seen in Central and South USA and South SW and NE Asia as well as the Eastern Arctic Sea as well.

NAO and AO remains for this period Positive and a Zonal Pattern with full Amplification- Low P areas with Deep Cyclogenesis as well.

USA and Europe in some Parts Cold and Windy or Less Wind lots of Record Breaking Cold Spells right now and continued next 15 days- and no Sunspots Flaring, but lots of Coronal Hole High Speed Streams (Two or three of them this month). Good for Northern and mid latitude Skywatchers looking for Aurora Borealis.

More Clustered area of Sunspots moving toward Earth Facing they are over the Sun NE limb!- heading toward >>>.

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AO progged to drop after the 16th, trouble is it looks like this is going to be caused by shallow surface highs which arn't that useful. Nevertheless a falling AO is nothing but good news, even if we have to wait 5 days until it occurs. There is relativly little scatter until xmas eve by which time the AO is still positive but much lower than it is now. After xmas eve the scatter sharply increaes, indicating that perhaps options may open thereafter for cold spells and we will see the familiar ensemble runs with the odd chart hitting -10C, perhaps we could expect snow and cold by new years day at the absoltue earliest? 

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The transition to somewhat more unsettled conditions is still shown on the 12z GFS. As for no big change int he output, I would argue that the overall pattern is still largely similar. There's has been little "continental influence" for much of the north and west but now parts of the south and east are about to lose what there was. The overall pattern though is a mobile one with high pressure over mainland Europe and a generally zonal pattern. Perhaps if the Euro High continues to shrink away south a little more then there could be cooler incursions of Pm air at times but also some very unsettled conditions.

http://www.wetterzentrale.de/pics/Rtavn1861.png 

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Yes agreed - fairly strong evidence now that the transition to a mobile and more maritime type is well underway, and slowly with time the mean jet looks set to sink south which unfortunately means the UK becoming more prone to being pummelled by low after low.

What is not being shown with any conviction is any sort of MLB or HLB anywhere in our neck of the woods.

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The GFS ensemble for wind direction and strength sums it up perfectly:

850hPa wind: http://www.meteociel.fr/cartes_obs/gens_display.php?x=306&y=141&run=6&ville=Londres&runpara=0&type=5&ext=1

Never gets north of west

Surface wind: http://www.meteociel.fr/cartes_obs/gens_display.php?x=306&y=141&run=6&ville=Londres&runpara=0&type=4&ext=1

All between south and south-west

 

 

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Looks like a very unsettled and often wet period

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Rather similar to last Xmas & New Year quite possibly.

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I might get shot for this but strat warms up by about 30deg between Dec 20 and 26 right over blighty at 10hPa level on the 12z.

I know this isn't going to produce anything either predictable or immediate downstream but it is on the model.

Other than that looking zonal, mainly average zonal not cold sadly. But a change from what was predicted a couple of days ago - suggests all is not lost.

I promise this is the last time I mention the strat.

I would say a strat warming over the UK is, if anything, bad for cold prospects. All it seems to do is shrink and concentrate all the cold temps over the arctic which would correspond to an intensified PV. Compare to the strat warming last year:

http://modeles.meteociel.fr/modeles/gfs/archives/gfsnh-2013010512-10-6.png?12

With the cold temps actually displaced towards the UK. 

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GFS, UKMO, Strat GFS NOAA etc.

The 10 days before Xmas Day and the 4 days after it are often with areas of Deep Low Pressure with short mild Sectors followed by Colder Sectors that is likely imply Gales and Severe Gales Evernote Stormy, Bands of Heavy Rain, and lots of Scattered and merged heavy Showers with Hills and Mountains even South and West plus North UK some Sleet and Snow, even in the rain, but lower areas Rain and Sleet more likely.

Very Cold Arctic Low pressure Vortex, with Strat warming in the mid lat belt! that in USA and Asia too- to its West and in the Vortex and all the way across N and NE USA Greenland Finland and UK NW Europe and NW Russia PV Vortex Troughs of major and Short waves all combined.

Temperatures will range from a 2 deg above average to dropping down 2-4 deg C below Average at times.

The Cool Centre and Surrounded by High Temps PV Vortex Spreads out and the Highs Strengthen it's a Track from the Arctic to Mid Lattitudes on West to East Strong Jetstream.

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What I can see of the ECM is the ghost of that great run 2 days ago. Its basically the same except does everything halfheartedly. Jet isnt as far south, E siberian high is shallow, LPs further west, less amplification over scandi e.c.t. But its a start. 

 

Actually that 240 chart isn't actually that bad, shame its so far out. Interesting point is the two pockets of anomolously warm and cold air over america. I wonder how these will interact, the warm pocket has made it to just south of newfoundland. If the warm pocket can somehow get north of the cold pocket than that would weaken the PV rapidally. 

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I imagine that if over the next 12 days we were to Observe the GFS, UKMO and the ECMWF models as they will and we will be following closely- There's often Quite high chance of a two Week period of Deep North Atlantic to UK and West plus North Europe Wet and Windy even locally widely Severe weather likely.

This I will be looking at in interest at least if offers Colder and Wetter Weather, though it will at times be mild in between Colder Spells, and with hail rain and snow plus Thunder and Lightning it looks often darted with major Deep Low's, though some brief ridges of High pressure will be taken well as a break and rest until the following and the next etc arrives.
12z ECMWF update is very impressive Weatherwise!.

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3 days ago - we were saying how this will be a very mild xmas.

then up pops something like this:
http://cdn.nwstatic.co.uk/gfsimages/gfs.20131211/12/300/hgt500-1000.png 

Potentially very wintry (for a short while) potential for some heavy snow over higher ground from mid central england northwards, and slushy ness on lower - FI of course, but worth noting.

Ok - its not the beast , but Ive seen very heavy falls of snow above 150metres come from similar scenarios in Wales.

If i recall - there was a similar scenario on the charts yesterday or the day before?

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