Model Output Discussion 17th Dec.2013-12z onwards.

[bluearmy]

Almost a split!

 

 

 

no almost about it snowman - its a very split upper vortex (again)

[ITSY]

Almost a split!

 

 

 

Was just about to post that. If you also look at the tropesphere, the lower level vortex is virtually split by the end of the run as well, with high pressure starting to become more prominent around lapland and the arctic - so plenty of room of optimism if nothing else. In the short term though, the storminess and rainfall totals look quite onimous, with another 100+mms possible in some north and western parts by this time next week

[Purga]

Tentative signs of a change appearing in the GFS 06z FI output

Some very cold uppers edging into Western Russia and Eastern Europe and a battle ground scenario in train. The Vortex is still very strong over Canada / W Greenland however so an uncertain outcome certainly at this range.

In the meantime and reliable range storms and potential flooding continue to be a concern to many areas

[stratty]

Almost a split!

 

 

.......just hope that when the cracker is pulled that the presents spill to our little side of the world. Massive potential in the later stages of the 06z ......................just gotta get through more wind and rain (again) first.

[SMU]

Not much to add this morning- a decent ECM- looking at the 10 day Mean & Ian F's post I would hazard a guess that above 25-30% of the members now show a blocked theme- as that big hole of nothing to the NNE will fill with +VE heights

 

the KNMI extended show around 25% from the EAST- however because we are in a sinking low pressure scenario that number for Scotland may be double that...22

 

http://www.weerplaza.nl/15daagseverwachting/?type=eps_pluim

 

S

[Frosty.]

I think while viewing the Gfs 06z op run in the later stages it's best to look at the bigger picture rather than what the uk weather shows, there is bitter cold to the northeast and northwest and actually the uk end up on the cold side..so..looking beyond all the angry looking stormy charts..i'm dreaming of a beast from the east

[Iceaxecrampon]

BOOM...

 

 

 

....and mild as hell. 

 

Ian

[cooling climate]

The building blocks towards a much colder outlook later in January are slowly coming together

I feel. The ECM and the 06z GFS run in the extended output give a good indication of where we

are headed with a amplification and regression of the pattern as the forecasted warming in the

stratosphere works its way down through the lower atmosphere.

Although output is likely to be volatile in the longer range due to what is happening

in the upper atmosphere.

The 1mb temperature strat charts taken from instant weather maps show the warming directly

over the pole.

[Iceaxecrampon]

Epiphany looking rough

Agreed - didn't see your post - sorry for duplication.

 

Ian

[Frosty.]

BOOM...

 

h500slp.png

 

 

....and mild as hell. 

 

Ian

Not sure about BOOM..I think that chart spells DOOM for the northwest of the uk if it verified  

Edited December 30, 2013 by Frosty.

[winterof79]

It only requires a short lull  from the zonal express for the Atlantic ridge to take its chance

http://www.meteociel.fr/modeles/ecmwf/runs/2013123000/ECH1-216.GIF?30-12

http://www.meteociel.fr/modeles/ecmwf/runs/2013123000/ECH1-240.GIF?30-12

as has happened many times before at this time of the year

http://modeles.meteociel.fr/modeles/reana/1946/archivesnh-1946-12-27-0-0.png

 

 

With the heights over the Arctic there is always a chance of a quick pressure build to our N/E too.

http://modeles.meteociel.fr/modeles/reana/1947/archivesnh-1947-1-5-0-0.png

http://modeles.meteociel.fr/modeles/reana/1947/archivesnh-1947-1-1-0-2.png

 

So on the face of it ECM 240 we would like to verify with the cold building

http://www.meteociel.fr/modeles/ecmwf/runs/2013123000/ECH0-216.GIF?30-12

[terrier]

Looking at most of the current output I can't see anything of interest out to day 10 at least with more problems with rainfall. Also just read the met monthly outlook and it's grim reading for cold right out to end of jan.

[Summer Sun]

Looking at most of the current output I can't see anything of interest out to day 10 at least with more problems with rainfall. Also just read the met monthly outlook and it's grim reading for cold right out to end of jan.

 

They still see signs of it turning less mild though so its not all doom and glum

 

Some signs are also emerging to suggest temperatures being less mild in general terms than during the first half of January, with the possibility of colder weather later in the month.

[ARNOTT ad]

Looking at most of the current output I can't see anything of interest out to day 10 at least with more problems with rainfall. Also just read the met monthly outlook and it's grim reading for cold right out to end of jan.

Then you must be reading the wrong stuff because it mentions possibility of long range cold and hasn't even been updated for today's yet!

[TSNWK]

They still see signs of it turning less mild though so its not all doom and glum Some signs are also emerging to suggest temperatures being less mild in general terms than during the first half of January, with the possibility of colder weather later in the month.

"Some signs are also emerging suggesting temperatures being less mild in general terms than the last couple of weeks, and perhaps even significantly colder late in the month" - were the exact words, unlikely to change today as driven by EC32 I believe, so be interesting to see what Tuesdays update suggests.Cheers.

[Summer Sun]

Then you must be reading the wrong stuff because it mentions possibility of long range cold and hasn't even been updated for today's yet!

 

They have updated the 6 to 15 and 16 to 30 dayer this morning see my post above

Edited December 30, 2013 by Summer Sun

[terrier]

Then you must be reading the wrong stuff because it mentions possibility of long range cold and hasn't even been updated for today's yet!

if you look at there monthly outlook it has updated which it does every Monday and it says those wanting cold and snowy conditions it doesn't look good

[Blizzardof82]

It only requires a short lull  from the zonal express for the Atlantic ridge to take its chance

http://www.meteociel.fr/modeles/ecmwf/runs/2013123000/ECH1-216.GIF?30-12

http://www.meteociel.fr/modeles/ecmwf/runs/2013123000/ECH1-240.GIF?30-12

as has happened many times before at this time of the year

http://modeles.meteociel.fr/modeles/reana/1946/archivesnh-1946-12-27-0-0.png

 

 

With the heights over the Arctic there is always a chance of a quick pressure build to our N/E too.

http://modeles.meteociel.fr/modeles/reana/1947/archivesnh-1947-1-5-0-0.png

http://modeles.meteociel.fr/modeles/reana/1947/archivesnh-1947-1-1-0-2.png

 

So on the face of it ECM 240 we would like to verify with the cold building

http://www.meteociel.fr/modeles/ecmwf/runs/2013123000/ECH0-216.GIF?30-12

This is what I was referring to yesterday when I asked a question, I know no one winter will not be the same even if they look similar but at least coldies can take some hope by looking at Winter 1946/47 and how that evolved.

[bluearmy]

Looking at most of the current output I can't see anything of interest out to day 10 at least with more problems with rainfall. Also just read the met monthly outlook and it's grim reading for cold right out to end of jan.

So what rocks your boat then terrier? some extremely low dam air headed across the atlantic this coming weekend and further deep depressions possible. also, the mystery of the atlantic ridge at day 9 which could lead to any number of extended solutions. i assume from your post that you are a coldie in which case, you are indeed struggling although, given your location, a surprise or two isnt out of the question.

[Jason M]

Latest set of GEFS are not particularly inspiring it must be said. Its a very zonal set for the most part with little obvious change going forward. Most of the colder spells are very brief and don't have adequate 850s associated to make any impact.

A few interesting charts are shown within the individual member runs but the overwhelming signal is for low heights to our immediate west / north west with lots of rain and wind.

[damianslaw]

Had little internet access these last three weeks - however, on viewing today for the first time this season, I can see signs of a possible pattern change emerging to something much colder as we head towards the middle of January - all thanks to development of heights building strongly over NW Russia - ECM and GFS are both showing these heights in situ at the 240 hr range, with heights building north towards Svalbard in response to pressure being waned on the strong candian vortex.

 

At the same time the jet for the foreseeable future looks like powering on quite a southerly course but in time becoming more fragmented and buckling, so a potential battleground scenario could develop with the longwave trough becoming unstuck over the country in time thanks to heights to our NE, low heights would then be forced to move SE into central europe and voila we are then exposed to a NE blast.

 

So all eyes on developments to our NE in the coming days, as it is likely to be developments there which will dictate the pattern as we head through January and how they interact with the atlantic low. In the meantime it remains as volatile as ever with rain and gales and temperatures a little above average for many, but more average in the north.

[johnholmes]

if you look at there monthly outlook it has updated which it does every Monday and it says those wanting cold and snowy conditions it doesn't look good

 

I suppose it as always depends on how you interpret their words, and if you are a glass half empty or half full sort of person.

To me reading their 16-30 day outlook they are, and Ian F has commented in this vein following his pre broadcast discussions with the senior man at Exeter, they expect colder conditions later in January over and above the temporary colder incursions during the unsettled spell we are currently in.

[IDO]

The 06z op has little support after D10, with respect to pressure and 850s:

 

   

 

Yes, the GEFS are a poorer run than the 0z for cold. The 0z had 105% points of snow chance; only 35% points for the 06z:

 

 

A rather basic method but you get the point. Little potential in FI either, but its the 06z and I am no fan of this run so hopefully just a blip. Especially as the crucial time of vortex disruption from Canada remains uncertain, spread:

 

You can see the downstream effects from the uncertainty with respect to the Atlantic and Scandi ridges.

[lassie23]

SW will hopefully be large enough over Greenland and Newfoundland to disrupt the polar vortex. If we are really lucky, it will split it, then we should prepare for a colder second half of January with the S word creeping into the forecast. Until then, the models will continue to churn out atlantic storms and mild weather. Poor wildlife, the animals and insects think it is spring.

[Mucka]

As of yesterday, around 20% of the EC members closed on an anticyclonic theme so it'll be interesting to see if that potential outcome develops further.

 

 

Hi Ian,

Are they still "discounting" anything other than a Westerly flow through to mid month at the very earliest?

and if so does that take account of an interruption to that flow such as the latest ECM?

In other words even if we get stronger Atlantic ridge and deeper European trough are they expecting it to be quickly brushed aside by a renewed Atlantic onslaught?

 

Thanks

Edited December 30, 2013 by Mucka