Model Output Discussion - 31/10/2014 and Beyond

[SMU]

http://www.meteociel.fr/modeles/gefs_cartes.php?code=4&ech=6&carte=1&mode=0

 

This is the best 12z ensemble & has identical shades of 2010-

 

http://www.meteociel.fr/modeles/archives/archives.php?day=21&month=11&year=2010&hour=12&map=5&mode=0

 

The ECM was similar on the 00z & signalled the vertical advection over western Greenland....

 

Something to keep an eye on...

S

[phil nw.]

Yes pretty much agree with your thoughts SK,nicely put.

We can see that there's a lot of possibilities for a cold UK pattern if-and that's the key word-the wave 2 activity continues and builds towards Greenland.

We just have  the beginning's of such a setup but the current modelling shows the heights just fail to tip the balance enough to split the Atlantic flow and build a solid High to our north.

We do see some  +ve height anomalies up there but they currently fail to push the jet far enough south so that the UK remains in the firing line for those Atlantic lows for the time being.

The difference with the earlier ECM Op was it's apparent bias to overcook those heights and thus modelled the easterly at day 10.

Shortly we will see how it handles this on it's 12z.

It would't surprise me to see that again. 

[Mucka]

http://www.meteociel.fr/modeles/gefs_cartes.php?code=4&ech=6&carte=1&mode=0

 

This is the best 12z ensemble & has identical shades of 2010-

 

http://www.meteociel.fr/modeles/archives/archives.php?day=21&month=11&year=2010&hour=12&map=5&mode=0

 

The ECM was similar on the 00z & signalled the vertical advection over western Greenland....

 

Something to keep an eye on...

S

 

 

GFS 12z ensembles at day 10 are about 50/50 between some kind of weak Atlantic or North/Easterly based flow which is a continued improvement. 

Of course there is no real signal for deep cold or a freeze up as yet but the colder/more blocked signal has definitely been strengthening over the last couple of days or so.

 

Asking for snow to settle in November is a big ask but personally I would be more than happy just to see some snow fall to low levels as a primer for what is hopefully a great winter to come for cold lovers.

Edited November 8, 2014 by Mucka

[MR EXTREMES]

Yes pretty much agree with your thoughts SK,nicely put.

We can see that there's a lot of possibilities for a cold UK pattern if-and that's the key word-the wave 2 activity continues and builds towards Greenland.

We just have  the beginning's of such a setup but the current modelling shows the heights just fail to tip the balance enough to split the Atlantic flow and build a solid High to our north.

We do see some  +ve height anomalies up there but they currently fail to push the jet far enough south so that the UK remains in the firing line for those Atlantic lows for the time being.

The difference with the earlier ECM Op was it's apparent bias to overcook those heights and thus modelled the easterly at day 10.

Shortly we will see how it handles this on it's 12z.

It would't surprise me to see that again. 

yep garden path i expect the ecm will still go all guns blazing,

but possibility that the greenland height pattern will moderate this evening or tomorrow.

 

but all is not lost its far to early and extremely rare for sustained cold this early in nov it worth keeping a close eye on the polar vortex though!

is it going to stage the come back.

 

not much vortex over the state side of the pole but is it about to relocate certainly looks hard for the vortex with that huge wedge of heights cutting through the pole.

it would not suprise me if we have a pressure rise over the uk with in the next two weeks or towards december.

but its by far not the end of winter.

 

id expect the ao to rise over the next couple of days if not sooner.

i like the ecm but year after year im starting to feel that anything beyond t144 should be taken with a pinch of salt.

[Purga]

Very wet prospects of immediate concern for many areas and hopefully not an early re-run for those badly hit last winter.

 

GFS FI showing a move to heights developing over Europe and a very mild regime establishing

GFS Parallel a somewhat different FI with the N blocking holding more in stu

So an unclear further trend after the current wet & windy period courtesy of the displaced southwards jet.

[Mucka]

I think the one ingredient that has been conspicuous by its absence so far but could most help secure cold prospects is some decent WAA up the Western side of Greenland to help cut off the Atlantic and secure a block in the region should we get heights to retrogress.

So far we have some weak attempts at ridging that help to disrupt incoming lows but we need the pattern backed further West with the jet digging further South giving more amplification to the pattern. Around day 9/10 offers a window of opportunity but so far no model has delivered.

It is very hard to see any block or anomalous heights to our North being sustained for long without being reinforced so let's hope we can see some signs of that on tonight's ECM or other output soon.

If we don't all is not lost because any failed block should cause some further amplification as it sinks to lower latitudes and it may be a case of needing more than one bite at the cherry.

Great early season model watching though for the enthusiast.

Edited November 8, 2014 by Mucka

[shaky]

What a beautiful 96 hour chart from the ecm!!even better than the gfs I think.........

[Barry12]

This is only day 5!

 

 

[Barry12]

DAY 6 IS CRAZY!!!

 

[Banbury]

DAY 6 IS CRAZY!!!

 

Get some WAA going up to Greenland and we are laughing

[minus 9]

Dont post very often but i think now is the time. The northern hemisphere charts are looking fab for cold in the long term. Ecm is leading the way.

[Cloud 10]

The 12z ECM seems to be accelerating the split in the vortex,even compared to the 00z.

 

 

 

[David Morse]

Welcome to the forum David.

Perhaps put your location up please.

 

I'm signed in with FB and I'm posting from Dublin.

[blizzard81]

DAY 6 IS CRAZY!!!

 

I am a little concerned about the lobe that spins off the vortex over the north pole though.

That could scupper the cross polar heights.

[Polar Maritime]

I have just deleted a post, Please think before posting and keep on topic.

Thanks PM.

[Snowy L]

Link between the UK low and West Atlantic low is gone! Hopefully that is enhanced in day 7+, need that high pressure to move west into Greenland. Though we have already seen a massive shift west in the 12z compared to the 00z. Slowly getting there!

[Jonan92]

Quite nice

 

[Barry12]

Is that cold over Scandi going to hit us!?

 

Edited November 8, 2014 by Barry95

[SMU]

http://www.meteociel.fr/modeles/ecmwf/runs/2014110812/ECH1-168.GIF?08-0

 

Vertical Advection over Greenland.....

[Cloud 10]

Scandinavia into the freezer at 168 hrs.

 

[Banbury]

 

 

This is looking very good .......................too good to be true...........surely?

[blizzard81]

The 168hr chart confirms what I thought. That spin off low from the vortex over the pole is helping

the vortex to fight back with a vengeance!!

[Dancerwithwings]

I'm signed in with FB and I'm posting from Dublin.

Phil nw, was implying put your location in your profile

[pad199207]

This 12z ECM is Wonderful!

 

Too good to be true though methinks!  #Onerun

Edited November 8, 2014 by pad199207

[David Morse]

Because the PV descended far enough south to reach the Northern USA. That elongation meant that the USA got lucky (or unlucky if you don't like that sort of thing). When the PV did start to break up the bit that had reached that part of the US was strong enough to hang around for quite a while.

 

 

 

The GFS isn't half slow now but the added resolution up to 240 hours appears to be giving it greater consistency.

 

LOL OK Paul, I was being some what facetious with my earlier post; I'm well aware of what happened in Jan '14 with the PV. My issue is that the same scenario in late November 2014 doesn't inevitably lead to the same outcome but it is the most probable outcome, i.e. that the USA will see an cold period and we will get lashed out of it with storms. As opposed to the very early onset of an exceptionally cold spell which is not indicated at this point in the ensembles, when the majority of them start aligning I'll start to consider it; but the outlook says mixed and stormy not cold and frosty.