Model Output Discussion 26/11/2012 18Z onwards

[swfc]

we need the waa pushing threw and the low going north past the tip of greenland for this to be pulled out of the fire.the high behind the low coming out of the usa isnt helping either

[Snowy Easterlies]

Well the more level headed folks prevail once again. Abused and scorned by those who should know better which must be intimidating for newbies coming on. Same every winter sadly.

The snow risk maps don't show much encouragement for many except in Scotland except deep in FI land. Note I've done a 12 hr step so may have missed a short snow fest.

So cool any major snow confined to short periods away from Scottish hills and remaining unsettled until deep FI when high pressure takes over which is unlikely to happen as any beast from the east at that time period.

i have posted a lot this morning i suspect someone will shoot me down for being realistic, sorry i don't do blind faith, these charts are nothing special at all, can someone prove otherwise apart from saying something like "T120 is FI, the models under do blocking" lets be honest apart from the UKMO, the GFS and ECM have being mediocre for quite a few runs now

the ECM is not as bad as last nights run but the cold soon gets swept away by T168 anyway, yes it may not be mild by then but average is not what we want is it ? and lets be honest even cold and dry is not enough its snow we want

Edited November 27, 2012 by Snowy Easterlies

[Mucka]

we need the waa pushing threw and the low going north past the tip of greenland for this to be pulled out of the fire.the high behind the low coming out of the usa isnt helping either

That possibility is long gone I fear. We are looking for a slider now and ECM isn't a million miles away and would probably produce some transient snowfall for some.

Edited November 27, 2012 by Mucka

[A.J]

Watch out chaps!....The other side of the coin, the glass half full troop are waking up, and as the old saying goes...."Hell hath no fury as a coldie scorned"....You have been warned....lol

Despite the somewhat negative stance on a lot of the overnight posts, credit where credit is due...You are all official 'Hardcore Model Watchers'...lol

[Mucka]

Talking of glass half full ECM isn't far away from being a good run and hints at what is possible if we can get a slider and everything backed West. Pulling cold air back in from the North by 192.

Edited November 27, 2012 by Mucka

[Snowmad79]

There is good news and bad news this morning. The bad news is the models are a disaster and the outlook is terrible and the way of the pear.

The good news is..... the supplies are in:

[cooling climate]

Very happy this morning with the output out to t120. Remember ECM on Sunday had

the Atlantic pushing through at t120 and here we are some 36 hours later at t120

and lovely cold charts from the UKMO and ECM.

Hats off to the UKMO I think.

Beyond t120 we really are very close to a frontal snow event across the country, a

tweek here and there and the UK could easily stay in the cold zone with slider fronts

edging just far enough south for cold and snow to be maintained over the UK.

The t168 chart on the ECM the UK still covered in -2c 850's.

[Snowy Easterlies]

Talking of glass half full ECM isn't far away from being a good run and hints at what is possible if we can get a slider and everything backed West. Pulling cold air back in from the North by 192.

but by T216 we are back in a southwesterly and there is a deep depression in the atlantic so not even a good FI, we can all hope for a slider but the big guns are not showing this currently

[swfc]

Ecm picks up from ukmo later in the run and looks quite on the money.Colder in the mid term but the nh charts look a bit naff to my obv untrained eye

[karlos1983]

Game, set & indeed match. IMO 😴

[Snowy Easterlies]

Very happy this morning with the output out to t120. Remember ECM on Sunday had

the Atlantic pushing through at t120 and here we are some 36 hours later at t120

and lovely cold charts from the UKMO and ECM.

Hats off to the UKMO I think.

Beyond t120 we really are very close to a frontal snow event across the country, a

tweek here and there and the UK could easily stay in the cold zone with slider fronts

edging just far enough south for cold and snow to be maintained over the UK.

The t168 chart on the ECM the UK still covered in -2c 850's.

yes cold but dry, its snow we crave, also i don't understand how you can be very happy, unless you live on a hill or in scotland, who knows we might end up with a slider but as i said the models haven't really shown this yet and it will probably only be transient snow anyway, we haven't seen a good ECM for some time now not even in FI apart from potential heights starting to rebuild, not even a brutal easterly at 216 for example

Edited November 27, 2012 by Snowy Easterlies

[Liam J]

Well finally the UKMO has woken up and got a whiff of the coffee, it was underplaying the eastwards movement of the Atlantic.

T144 charts from the GFS, ECM & UKMO - handling the evolution quite badly over the last few days, all now more or less on the same page.

Edited November 27, 2012 by Liam J

[swfc]

Very happy this morning with the output out to t120. Remember ECM on Sunday had

the Atlantic pushing through at t120 and here we are some 36 hours later at t120

and lovely cold charts from the UKMO and ECM.

Hats off to the UKMO I think.

Beyond t120 we really are very close to a frontal snow event across the country, a

tweek here and there and the UK could easily stay in the cold zone with slider fronts

edging just far enough south for cold and snow to be maintained over the UK.

The t168 chart on the ECM the UK still covered in -2c 850's.

Good points made there .Where and how would you see the cold be sustained given the blocking has all but vanished?It looks just unsettled and to be fair pretty mobile .The pv has me baffled to be honest!! Edited November 27, 2012 by swfc

[IDO]

I think even the doubters will come on board today. The trend is for a cooling down for the next 3/4 days, then 24-72 hour cold snap. Some snow principally to high ground and coasts (details always vague re snow though). Then the Atlantic pushes in. MO is edging in this direction. ECM also, but less progressive than the GFS.

So that question looking resolved. The next is how far the Atlantic incursion goes. The GFS 0z pushes in positive 850s to the far SW for a day or so before cooler uppers from the NW (0c to -3c) flood back, probably 36-48 hours pre the ECMW (less cold for 24-36 hours around the 6th). Potential for battleground snow on all models but miles too early to say if and where.

In FI on the GFS, from about the 7th December, there is an easterly but this is a cold outlier on the ensembles: http://cdn.nwstatic.co.uk/ensimages/ens.20121127/00/t850London.png

From there the 850s mean rises with a trend towards milder uppers. I suspect if we miss this first shot then it looks like we will have to wait to the last 10 days of December for another chance of a prolonged cold spell. Still support to stay on the cool side and the ensembles suggest a cold day or so may still happen right out till 13th December but nothing unusual. Still no sign of a zonal flow, likely due to the amplified troughing forecast for the US: http://cdn.nwstatic.co.uk/gfsimages/gfs.20121127/00/264/npsh500.png. North Europe and Russia continues to cool: http://cdn.nwstatic.co.uk/gfsimages/gfs.20121127/00/204/h850t850eu.png. Good for later in Winter.

I suspect the reason why the GFS defaults in FI to zonal is because that is the nature of the UK weather, it is Atlantic influenced. Even when blocking is unprecedented, it is there waiting for it chance, be it a pesky short wave, a trough positioned too far north or an upstream low taking a wrong turn. That is why although the strat experts are mind numbingly brilliant I do not take it as gospel that the cold will reach our shores other than as a passing tease. Hoping to be proved wrong...

[Snowmad79]

If I'm honest with myself, there is still a small window of opportunity and that is that +72hr could be considered FI. Are we really so certain that they have enough data from the Greenland and arctic area to feed the models. At 72-96hr, what if the LP near Greenland is being over done ? it still looks as though it "could" go north in those 2 frames.

Maybe I'm clutching at Straws or maybe it is still possible ?

[Mucka]

but by T216 we are back in a southwesterly and there is a deep depression in the atlantic so not even a good FI, we can all hope for a slider but the big guns are not showing this currently

It is not called FI for nothing though, I'm just saying that FI is 120+ and with some tweaks in our favour all is not yet lost. WE need the blocking to hold a little more and force the pattern West and then the low disrupt energy South instead of East unlike UKMO both of which are possible. I'd say a decent slider has about a 1 in 8 chance based on current output but those odds are not hopelessly long. Anyway if it doesn't happen we are only just getting into December so although it would be very disappointing and frustrating we will soon get over it and be ready for the next chase and a white Christmas.

Edited November 27, 2012 by Mucka

[snow drift]

It is not called FI for nothing though, I'm just saying that FI is 120+ and with some tweaks in our favour all is not yet lost. WE need the blocking to hold a little more and force the pattern West and then the low disrupt energy South instead of East unlike UKMO both of which are possible. I'd say a decent slider has about a 1 in 8 chance based on current output but those odds are not hopelessly long. Anyway if it doesn't happen we are only just getting into December so although it would be very disappointing and frustrating we will soon get over it and be ready for the next chase and a white Christmas.

Come on guys, lets go chase the next cold shot!!!!! What can go wrong??!!!

Edited November 27, 2012 by snow drift

[Snowy Easterlies]

Good points made there .Where and how would you see the cold be sustained given the blocking has all but vanished?It looks just unsettled and to be fair pretty mobile .The pv has me baffled to be honest!!

agree mate charts look pretty bog standard apart from this weekend where it will be cold and mostly dry, i think some cling onto the hope that blocking has been underestimated maybe it has maybe it hasn't ??? but the trend is for the atlantic to come in it might get delayed a bit thats all

[swfc]

Love it,ill tell the grandkids "again" to dust there sledges off!!!!

Come on guys, lets go chase the next cold shot!!!!!

[Snowy Easterlies]

Come on guys, lets go chase the next cold shot!!!!! What can go wrong??!!!

i need a rest now, we could be chasing phantom cold spells all winter, these models are like trolls

no eye candy in FI from the ECM pretty bog standard stuff, despite the PV not being ramped up, some look at the NH profile a bit too much and not see whats staring them in the face on our island

Edited November 27, 2012 by Snowy Easterlies

[Liam J]

Don't despair guys, looks like an increased risk of a white Christmas according to the CFS daily, unfortunately we have to endure a zonal attack before we get there!

[Duane S.]

I think you'd have to see we may count ourselves a little unlucky here (just as everything went our way in Nov/Dec 2010, it has not this time around) BUT the theme continues for a cold start to December. And to my eyes there is little way back to sustained mild from what's currently setting up.

I've seen the models firm up on some aspects over the past 3 days or so. That the ridge will be flattened out, even with an increasingly deeper low off the eastern seaboard residual energy is being taken across the Atlantic to us. So after a cooldown this week, we are looking at a 'milder incursion' but the theme will stil very much be cold and there will be plenty of chances of snow even with that setup, albeit more likely in the North. Thereafter I think w are going to see increasing better charts as the Azores high once again looks to ridge and help set up some HLB as we go through the second week of December.

[swfc]

i need a rest now, we could be chasing phantom cold spells all winter, these models are like trolls

Im thinking or hoping it was tongue in cheek that comment????.Anyway i think the ukmo has actually not been really out of kilter in its forecast.Pretty solid then just follows the ecm route which looks about rite to me

[swfc]

Don't despair guys, looks like an increased risk of a white Christmas according to the CFS daily, unfortunately we have to endure a zonal attack before we get there!

Cfs eh?ill get down the bookies asap hahaha

[Snowy Easterlies]

Don't despair guys, looks like an increased risk of a white Christmas according to the CFS daily, unfortunately we have to endure a zonal attack before we get there!

i think it will be dry as pressure looks to high on that chart, all conjuncture anyway, but i could put up with 3 weeks of zonal or euro high crap if it meant us having a white christmas and new year period