Seasonal. 

Usual rules apply. 

ECM (left-side) places that U.S. trough further south than GFS (right-side) at day 6. This has a significant impact on the pattern going forward;

The GFS version results in the low engaging with a sharp temperature gradient off the Canadian coast and bombing out, steering the jet on a SW-NE course that takes it north of the UK and allows a large ridge to build in from the Azores.

The ECM version prevents that development, keeping the low a weak feature until it eventually gets picked up by the jet days 9-10. The jet isn't steered north of the UK, instead continuing to drive low pressure to our shores which is intense days 8-9 much like the storm in the middle of next week - in fact a bit more intense. Essentially a repeating cycle of bombardment.

Assessing the support from other models, UKMO, JMA and GEM are all in line with ECM with that U.S. low and GEM really does track the ECM run remarkably closely out to day 9.

The ECM and GEM output is leaning towards a split polar vortex scenario in which one lobe is sat in the Pacific while the other covers Greenland and the Atlantic, still edging into Canada at times.

GFS is not far away, but the lifting of the jet north past day 6 focuses the lobe on our side over Greenland.

If we get something like the ECM and GEM output, it's a pattern capable of persisting for quite a while but would get a lot more exciting with some strong height rises over the Arctic. So it becomes a case of a loaded gun that needs firing. A stratospheric warming event, preferably a SSW, would do nicely. It's encouraging in this respect to see a trend to higher pressure close to the pole across recent ECM op runs.

It looks possible that wave breaking, linked to those vast blocking highs building across the U.S. and Asia, could produce such strat. warming, as suggested by the GFS 12z op run, which gradually increases the warming through lower res to give this day 16 output:

These charts are of course subject to possible large changes in terms of the rate and magnitude of warming so don't go holding your breath.

To follow up on my previous post, it appears ECM may also be seeing that warming going on:

https://twitter.com/MattHugo81/status/540611151743426560/photo/1

"Tropospherically and stratospherically something is brewing & 12z EC ENS clusters by 19th are very interesting indeed"

Worth noting that this is the model still projecting the MJO to be uncooperative.

After reading around, I've reached the conclusion that while a favourable MJO is a big help, plenty of strat. warming events and SSWs have occurred without the MJO lending a hand, implying that it's by no means the be-all and end-all.

Indeed SC 

Just had this insane GEFS ensemble solution pointed out to me:

900mb? Seriously?

It ends up driving the jet NE even more quickly than the op run did i.e. before the cold NW'rly can even turn up, so hopefully that monster won't verify, even considering it would be a new record pressure for a non-tropical cyclone.

Meanwhile the GFS 18z op run remains out of line with the 12z consensus as far as that U.S. low is concerned.

Apart from the low to the NE of Scotland in 6 days time being a tad deeper, the run offers little in the way of appreciable change from the 12z op run, except for very slightly stronger strat. warming.

The whole progression beyond day 5/6 hangs on that U.S. low so it could be entirely wide of the mark... or the combination of ECM, UKMO, JMA and GEM could be. One against four, where's your money? 

Looks like quite an active cold front on Sunday morning, with quite a defined back to it.  Could get some interesting weather inside it as it sweeps through.  Though its going to hit during the night, soo will probably miss it.  Sunday is looking crisp early on.

I remember a cold front we had hit us a few years back (prob around 2007ish?).  Temp went from something stupid like 11-12c to 3c in abut 20 minutes, a brief snow shower on the back and then the temp popped back to 5c. 

Looking further ahead, and still some interesting wobbles in FI - will pressure build to the east or not? certainly some interesting ingredients kicking up...

Really some strong trends showing up on the CFS, all the runs seem to be showing something interesting now. They all manage blocking of some description by the end of the year but some go a good deal further than that and somewhat sooner (blocking generally beginning sometime between the 20th and the new year). The most recent CFS run has cold Nerly by xmas and the beast from the east by the start of January, and its a real screamer on this particular run. 

In fact (and I'm not exaggerating) this is the coldest run I have ever seen on the CFS. 

Nice one Quatum - can you post the links on here?  Im not sure where im to look for CFS apart from the annomalies on here which are in monthly segments

That second drop in temps after the 9th is starting to tighten up again now, with the curtain of doubt held at around 13th Dec.  By the looks f the GFS we may have 1 or 2 more significant waves of sub -5c 850hPa air to hit us before maybe a chnage later in the month.  

Not a bad way to be entering into winter.  When considering most of the -5c temps stayed out into FI of the GEFS for majority of the last 12-18 months in some places.  

-16C, a sight to behold:

General Overview of the Situation:

Weather Alert for Tuesday 9th and Wednesday the 10th December: A Deep NW to Central mid Far North spanned Major PV Low NE Newfoundland, SW SE Greenland, Monday deepens rapidly and moves East SE across Iceland and also West and NW UK by Tuesday 9th, the Bracka Faxes and the UKMO plus GFS (all 12z today) back this up, A severe heavy rain and High winds PV Low with Abundant Tropical Moisture merging into Very cold Air in the Aforementioned NW and Central Mid and Far N Atlantic to Newfoundland then Greenland then Iceland then the UK, Wonds of upto 60-70 mph look possible (likely).

by Wednesday It sits across Mid to NE Atlantic and Over the UK especially the West and North areas, by then the Cold Airflow will cross all parts of the UK with Tuesday p.m's heavy rain replaced by more bands of heavy showers some merging to longer spells of rain, Temps a few degrees below Seasonal Average..., By Thursday next Week see below.

Cold Northerly flow with some widespread well scattered blustery sometimes wintry showers and pretty cold air from the NW across UK, But turns to High Pressure gradually from the West and particularly SW UK this moves across by the Afternoon.

Sunday to Monday Low Pressure brings cold NW and then Northerly airflow, with frost possible in Northwest by Sunday Night and more widely across the Country by Monday, but it briefly settles down with overnight frost Monday night to Tuesday a.m.

Also interesting is that Hurricane Typhoon now affecting East and Central Phillippines area West Pacific.

Some Areas of heavy rain in Central SW USA South Rockies and in East N USA midsection some quite heavy rain been visible via Satellite Maps there, plus Low Pressure two of them running ENE from Central West NW Pacific the other leads it to its East NE and one to SW off Alaska. ( Polar Low Pressure Belt driven by the Jetstream, and another Area of Low Pressure and wind / atmospheric rain system moving towards West SW California Washington et all, Seattle Los Angeles and San Francisco.

I am comfortable with this analysis very much hope fans are amazed at these developments.

The Cold air this Week affect South Central Europe, with some more heavy rains causing more flash floods, this Low Pressure will next week also Affect Tunisia and Some other parts of Northern NW Africa, extending across as always SE France Meditteranean and Italy Greece and Turkey.

What also is very amazing is the Areas of Large High Pressure spreading and sitting over affecting parts of Central and NW USA, I think, and some move to NE E Central USA with Areas of Jetstream Lows moving from SW to Central then Far East USA but more especially NE Canada far NE USA as well, with Central N Atlantic to West Central Azores and West N Altantic High Pressure areas that have sent Tropical Low's around their SW then move up far NW Altantic catch the Cold air and behind then the SE Canada High moves to NE E USA to join the and feed the large Central Mid North Atlantic High which spreads away from UK but does ridge in at times, this has already turned us colder and we are likely heading uphill and downhill with December Weather Sitaution at least for the first 11 days ahem.  Have a good Night all.

😀😅💦

I've seen colder. Every winter charts are posted up and tagged as "the coldest ever". Maybe one day they'll actually materialise. Maybe this winter eh? Maybe not. 

There should be some of us taking notice of what where and how the Typhoon will approach Phillipines East Central and NE see this link here:

http://www.gmanetwork.com/news/story/391079/scitech/science/typhoon-ruby-slows-down-why-that-might-not-be-good-news-for-us

It's slowed to 15 kmh from earlier 30kmh and if it this continues it will affect coastal and inland areas worser and the direction will be more difficult to judge, the drop in forward speed will make it stronger with more precipitation being heavier.

A windy and very mobile next 7-9 days with frequent spells of cool/cold polar maritime air interspersed by occasional brief ridges and drizzly tropical maritime air masses at times. Convective snow showers a distinct possibility over northern areas at times, especially over hills. Overall rather cool with the CET struggling. With sub 524 dam air reaching the south coast on Monday and again possibly on Thursday I will be hoping for some sharp photogenic cold fronts and also hope that a rogue trough or fizzling Cheshire Gap shower reaches here and gives me my first sighting of a wet snowflake since way back in early April 2013. 

Yes a few decent cloudscapes would be great - as would clearing the horrible cloud cover yesterday.
But as for the splodge of a wet snowflake - you might have to go looking for that!

Good analysis here as usual but not much has changed in the actual projections to mid-month: Mobile, changeable, near mean temps remains the order of the day.

HERE IS MY LATEST ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM 8AM TODAY FRIDAY DECEMBER 5TH 2014.

NEXT UPDATE SATURDAY DECEMBER 6TH 08:00

THE CURRENT GENERAL SITUATION A cold front will clear SE over England today with a cold and showery NW flow following. A further cold front will approach NW Britain tomorrow.

MODELS-2 WEEK HEADLINE Changeable with rain at times. Temperatures near average at times but generally rather cold and very windy too with snow on hills possible.

THE JET STREAM ENSEMBLE FORECAST The Jet Stream Ensemble forecast indicates the flow will continue blowing across Southern Britain over the longer term period this morning probably in an undulating pattern as warm and cold sectors pass by.

GFS OPERATIONAL The GFS operational this morning indicates quite a flat pattern made up of Low pressure crossing East to the North of Scotland and High pressure to the South and SW of the UK. This will bring predominently Westerly winds, strong at times. These will tilt NW at times delivering short spells of colder and showery conditions principally to the North and West while periods of less chilly weather with cloudy skies and occasional rain occurs at other times again especially towards the North and West. Amounts of frost and fog will be limited with too much wind and snow and ice problems will be limited to colder, showery periods and chiefly over the hills of the North.

THE GFS PARALLEL RUN The GFS Parallel run is not available until Monday of next week.

THE GFS CONTROL The GFS control run maintains a similar pattern but does show a greater and more extensive dip into a colder Northerly flow at times when wintry showers become much more pronounced across the North before milder weather returns a few days after. Elsewhere rain at times on a gusty west wind looks the order of the days with temperatures closer to average at times.

THE GEFS ENSEMBLES The GEFS Ensembles maintain a period of zonal Westerly winds over the next two weeks circulating around Low pressure to the North and High to the South. As some colder air interjects at times some rather cold and showery interludes occur across the UK at times, chiefly and most felt in the North where snow is possible at times.

UKMO UKMO today shows deep Low pressure to the East of Iceland and High pressure down near the Azores with a strong Westerly flow across the UK with squally shwers and sunny spells in rather cold conditions permitting temperatures to fall as snow over Northern and Western high ground..

THE FAX CHARTS The Fax Charts show a cold fronts crossing SE across the UK over the weekend and setting up a cold NW flow for a time with wintry showers before a ridge dampens these down early next week ahead of deep Low pressure to the NW by midweek.

GEM GEM shows a strong Westerly flow across the UK throughout next week turning NW at times as colder air digs down across the UK periodically. Low pressure remains deep and recurring to the North of the UK through the period with High pressure to the South. Rain at times will prevail with clearer, colder and showery periods as well when snow will fall over Northern hills.

NAVGEM NAVGEM is a little different this morning in that it takes next weeks deep and powerful Low pressure system South down the North Sea through the middle and end of next week filling as it goes but bringing ever deeper and colder air South with wintry showers for many and at least the chance of seeing a little snow for many with rather more across Northern and Eastern hills in particular.

ECM ECM this morning shows a windy week next week with troughs rushing East in the flow between Low pressure to the North and High to the SW of the UK possibly ridging North over the Atlantic later. All areas will see rain at times and with colder incursions affecting principally the North at first next week spreading further South to all areas later with the risk of wintry showers to quite modest levels at times late in the run even over the South. Though some milder interludes look likely over the South a lot of the time will see colder polar maritime type air keeping things on the cold side, chiefly in the North at first but more widely by the end of the run.

ECM ENSEMBLES This morning's Ensemble data shows a sinking Jet flow to the East of the UK and the UK falling on the Northern side of the Jet flow later. Low pressure areas continue to be shown to bring some wet and windy conditions with cold weather too at times, especially later when snow could become a feature for more parts of the UK and not just Northern hills.

NOTABLE TREND CHANGES FROM PREVIOUS RUNS Although the Azores High is shown to remain a thorn in the side for those looking for deep cold there is a lot of energy shown in a strong Westerly flow over the Atlantic to bring spells of tropical maritime air with rain at times with a growing chance that polar maritime air frequently over the North could make it's way down over the South too more coherently later in the period with wintry showers.

MY THOUGHTS For those that like mobile and strong Westerly winds bringing spells of rain followed by Wintry showers then the next few weeks could be yours. All models show a potent Westerly airflow blowing across the UK between deep Low pressure areas moving East repeatedly to the North of Scotland and High pressure well to the SW. Fronts in the flow will bring their own version of rain followed by clearer and showery conditions. Colder air in these showery spells will allow snow to fall on hills of the North and West and to quite modest levels in the far North. For Southern Britain any wintryness will be very fleeting and for many non-existent until later in the period when some output notably NAVGE and ECM drag the colder uppers down across the South of the UK too giving all areas a risk of seeing at least a little snow and perhaps quite a bit on upland areas of the North. Despite this wintry flavour to my thoughts this morning we muct remain mindful that we are in a Westerly regime and we need the Jet flow to dig further South than currently and the Azores High to play less of a role in suppressing any cold events for the UK and there are signs that this may take place later in the period. As many have said the weather patterns of this Winter so far are very different to where we were a year ago and with plenty of cold air up North this remains the direction we need to keep looking as we approach the run up to Christmas as I feel the best chance of snow for Christmas this year is dependant upon whether we are in a polar airmass behind Low pressure to the NE of the UK or not. I don't think we will see any cold from the East in time for Christmas and will have to wait for cold polar air on the rear side of one of these deep Lows to lower mainland Europe temperatures to levels which would encourage and support synoptics more condusive in bringing cold from that direction post Christmas.

I wouldn't they cant deliver naff all

 Latest from Matt H  very good read we have a chance this year

https://twitter.com/MattHugo81

any chance that you could cut and paste his tweet in here so that those of us at work (and can't access Twitter) can read his comments ?

cheers

No I cant get back to work  

Matts words

The signal continues for future warmings as we move beyond mid-month. Warming is even stronger above 5hPa

Tropospherically and stratospherically something is brewing & 12z EC ENS clusters by 19th are very interesting indeed.

 ta muchly

Some colder nights generally uk wise next week something we never had last year

http://www.meteociel.fr/modeles/gfs/royaume-uni/temperatures-2m/3h.htm

Yep - good assessments today 🙂 From a personal POV at least we will see some good cold fronts, occasional frosts and a good blow

Some cracking cyclogenesis off the eastern seaboard on the latest fax charts early next week :)

Must . .. resist . . . . oh, I can't do it.

Anyway, indeed, looks like classic old skool stuff where there is something for everyone in the next week or so.