Winter Model Discussion - The Hunt For Cold - 12th Dec

[Frosty.]

Interesting run the 06z, chucks the kitchen sink at us. Also it has Dec 46 sort of profile...

BFTP

It looks like a cold outlier to me, since it goes against the trends from the other models and is nothing like the gefs 00z mean, probably another con trick just outside the reliable timeframe.

[BLAST FROM THE PAST]

Just watched spotlight on BBC and the forecaster said that he'd seen something for the first time. A singular LP that covered and controlled the whole of the North Atlantic. Interesting piece of info. Wonder if JH has seen such a thing or other very seasoned campaigners. Its coming alright.....from the WEST.

BFTP

Here we go guys, this is just for fun BUT there is something relative about this post. The following chart has a singular LP that covers the whole of the North Atlantic.......

BFTP

Edited December 13, 2012 by BLAST FROM THE PAST

[Rocheydub]

Can't call it an outlier until we see the ensembles, who knows, maybe it's picked up on a new signal?!?!

I am however quite sceptical myself, and would be massively surprised if the low and high orientated like that. Just like I was when our missing beasterly was modelled!!!

Who knows, maybe the much maligned 06 has picked up a signal... Time as ever, will tell!

[Weather Boy]

Although I can understand why some are referring to this easterly on the 6z as a surprise, given the dire (for cold) model outlook over the past few days, it would NOT be correct to say that the idea of an easterly at this time range has never been toyed with before by the GFS (although never long lasting), as shown by my last post (link below) on 9 December:

http://forum.netweather.tv/topic/75219-model-output-discussion-8th-december-onwards/page__st__720#entry2441221

Only time will tell whether it is on to something or not. Little support so far, but lets see what the ensembles bring. It would hardly be surprising to see the op as an outlier or at least a colder member

[mountain shadow]

Something positive to discuss at the very least.

[snowblues]

Would the models start picking up any signals yet later in the outputs,from the warming strat forcasts that looks promising?or to early.

Edited December 13, 2012 by snowblues

[Frosty.]

Although I can understand why some are referring to this easterly on the 6z as a surprise, given the dire (for cold) model outlook over the past few days, it would NOT be correct to say that the idea of an easterly at this time range has never been toyed with before by the GFS (although never long lasting), as shown by my last post (link below) on 9 December:

http://forum.netweat...20#entry2441221

Only time will tell whether it is on to something or not. Little support so far, but lets see what the ensembles bring. It would hardly be surprising to see the op as an outlier or at least a colder member

Yes we can't dismiss the 6z but it really would be a shock if it verified and when I see cold FI charts I am now even more sceptical since the models got it so badly wrong last time, anyway, much milder from tomorrow onwards.

[TEITS]

GEFS control brings in a NE,ly.

Like I said this is unlikely to bring anything prolonged and infact the NE/E,ly flow (should it occur) might be so brief we don't pull in much in the way of cold uppers. However its still better that previous poor outputs and gives us something to discuss.

[Troubleatmill]

Quickly scanning through through the 06z ensembles there is not much to bring us festive cheer, think it could be one of those times to give the models a break for a few days rather than watching each one come through & hoping that its all been a bad mistake.

Things always look better after a couple of days break...hopefully :s !

Edited December 13, 2012 by Nick JB

[latitude]

Another way of viewing the 06Z is this.

Obviously the 06Z is quiet different opposed to other model runs. Now lets assume the opposite was showing and that all previous model output was showing a cold spell and then along came todays 06Z with a completely different output. Everyone would be in panic mode and the posts on this thread would say "Has the 06Z picked up a new trend", or "its going to be interesting viewing the 12Zs".

Never assume all cold spells downgrade and all mild spells verify because that is a flawed argument. These models don't have a mild or cold bias. so lets judge the output on its own merits. I shall be curious to view the ensembles.

The mild weather we have all been searching for after this little anoying cold spell could soon be over just before christmas...great. Is this a trend or will the mild hold out for us. We will have to wait to see if it was just one run.

Edited December 13, 2012 by latitude

[Severe Siberian icy blast]

GEFS control brings in a NE,ly.

Like I said this is unlikely to bring anything prolonged and infact the NE/E,ly flow (should it occur) might be so brief we don't pull in much in the way of cold uppers. However its still better that previous poor outputs and gives us something to discuss.

I don't think we are in a position to discuss the longevity of this potential north easterly yet , because how do we know what would happen after that? It may be that it allows a ridge in the Atlantic to build behind the low, or it may allow the high over Russia to pull west, infact it's not like it would go against the signals is it? I mean we have no PV our side of the pole , so with just the residual lows in the Atlantic with no PV feeding them surely it won't take much to kill the power of the lows as they come against a big block?

[Shunter]

Quickly scanning through through the ensembles there is not much to bring us festive cheer, think it could be one of those times to give the models a break for a few days rather than watching each one come through & hoping that its all been a bad mistake.

Things always look better after a couple of days break...hopefully :s !

the 06z ensembles ?

[Pixel]

Here we go guys, this is just for fun BUT there is something relative about this post. The following chart has a singular LP that covers the whole of the North Atlantic.......

BFTP

Presently illustrated here also very nicely:

http://www.meteo.psu.edu/~fxg1/HEMI500/5dayloopeur.html

[Troubleatmill]

the 06z ensembles ?

Just look on Meteociel Shunter you can see each run on there before for the graphs

http://www.meteociel...gefs_cartes.php

Edited December 13, 2012 by Nick JB

[No Balls Like Snow Balls]

I don't think we are in a position to discuss the longevity of this potential north easterly yet , because how do we know what would happen after that? It may be that it allows a ridge in the Atlantic to build behind the low, or it may allow the high over Russia to pull west, infact it's not like it would go against the signals is it? I mean we have no PV our side of the pole , so with just the residual lows in the Atlantic with no PV feeding them surely it won't take much to kill the power of the lows as they come against a big block?

Or more importantly how do we even know what happens before LOL

Edited December 13, 2012 by No balls like Snow Balls

[Heisenberg]

It looks like a cold outlier to me, since it goes against the trends from the other models and is nothing like the gefs 00z mean, probably another con trick just outside the reliable timeframe.

Hi Frosty,

Can you tell me why it would be ok for this colder option would be no good "because it goes against the trend" but last week when we were going to have snowmageddon and the models then started to show this dissolving and indeed going against the long term trend that it was accepted that it was going to turn milder?

I know thats what has happened but what makes the colder option less lilkely to happen?

If the trend is showing cold and something warm pops up, everyone takes it as gospel but if (like the 06Z) shows something cold while the trend is mild, then everyone says, its not going to happen and its an outlier etc....

Not having a go or anything but just curious why this happens time and again...

ta

[bluearmy]

I dont think the ens will give much help on this evolution. complex and maybe best left to ecm op to give best guidance although you have to smooth out any overcomplicated shortwave activity it picks up post day 6 and adjust accordingly. alernatively, just watch, take note and move on!

[Troubleatmill]

Hi Frosty,

Can you tell me why it would be ok for this colder option would be no good "because it goes against the trend" but last week when we were going to have snowmageddon and the models then started to show this dissolving and indeed going against the long term trend that it was accepted that it was going to turn milder?

I know thats what has happened but what makes the colder option less lilkely to happen?

If the trend is showing cold and something warm pops up, everyone takes it as gospel but if (like the 06Z) shows something cold while the trend is mild, then everyone says, its not going to happen and its an outlier etc....

Not having a go or anything but just curious why this happens time and again...

ta

Think it maybe that we are by default a 'mild' island and its so hard to get cold (or lasting cold) to our shores

Edited December 13, 2012 by Nick JB

[Man With Beard]

The 6z is the perfect example of how all the posts writing off the rest of December are just silly. I'm not saying this is what will unfold just that the weather is not as straight forward as some GFS runs out to 384 might look!!

ECM ens also have a scatter of members dipping around this time, have not looked at the postage stamps but maybe they are along the same lines?

Yes absolutely, if you look through T120 to T180 the block to the east pushes back - and I'm looking at Mr Shortwave coming from the easterly flow, now if that comes a little further south as GFS 06Z shows and joins up with Mr Decaying Low then the cold can come that little bit further west and hey presto. Funny I was looking at the 00z charts thinking it wasnt a mile away and then the 06z goes and does it. It's actually very close to coming off and far away enough into the future to upgrade (or of course downgrade). Stay tuned!

[TEITS]

I hope the ensembles in distant F.I change because they are simply shocking and probably showing some of the worst winter synoptics you could possibly imagine, yes they are that bad!

[BLAST FROM THE PAST]

Think it maybe that we are by default a 'mild' island and its so hard to get cold (or lasting cold) to our shores

Its darn cold for Dec right now though and the CET currently supports that. I think what is hard is to get sustained deep cold, raging easterlies and days to weeks of snow.

BFTP

[bradymk]

Its darn cold for Dec right now though and the CET currently supports that. I think what is hard is to get sustained deep cold, raging easterlies and days to weeks of snow.

BFTP

Yes Phillip Eden's climate UK figures for December so far. Well below average and it will take a lot to bring this to above average now. CET: (Dec 1-12): 2.1°C (-3.5 degC) E&W Rain: (Dec 1-12): 28.2mm ( 75 per cent) E&W Sun: (Dec 1-12): 37.6hr (200 per cent) © Philip Eden

[Matty M]

I hope the ensembles in distant F.I change because they are simply shocking and probably showing some of the worst winter synoptics you could possibly imagine, yes they are that bad!

Yep they re-form the PV to our north and result in true zonality. A horror show with back up from the ECM EPS

Edited December 13, 2012 by Matty M

[Suburban Streamer]

Here we go guys, this is just for fun BUT there is something relative about this post. The following chart has a singular LP that covers the whole of the North Atlantic.......

BFTP

and 6 days later.....

Like u said....just for fun

Edited December 13, 2012 by Suburban Streamer

[bradymk]

Yep they re-form the PV to our north and result in true zonality. A horror show with back up from the ECM EPS

Yes ensembles really aren't too great however the PV that does re-form may not be enjoying life for long if the potential warming forecast occurs which would result in disintegration of the PV in Jan and quite a large one if the warming occurs as currently forecast.

Edited December 13, 2012 by bradythemole