Model Output Discussion 1200 hrs 15/11/14

[snowmadchrisuk]

Longer term , the main difference between the gfs 6z and the 12z , is the 6z weakens the block to our East , where 12z keeps it 1055mb  .The longer we can keep that block to our East , the more time we will have for low pressure systems to dig South East and get an eventual retrogression  .

 

[Cheshire Freeze]

Look at that southerly flow at 300 hours on the GFS 12z, drawing right up to the Arctic!

Yep, repeated attacks at the vortex throughout the run. In my very honest opinion, from what I've seen of the NWP over the last week or so, this could turn into a perfect storm for cold as we enter December. It all looks very ominous for the vortex this winter, that's for sure.

[phil nw.]

Yes just running through the first 8 days of the GFS it's fascinating to see the Canadian lobe try to push out and then hit a brick wall.

The jet splits around the Iceland longitude and sends enough of it around the top to prevent the block from building too far north.

 

and this seems to be a repeating pattern with minor variations amongst the differing model runs.

 

No Atlantic breakthrough as yet but at the same time the cold starting to build further east remains out of reach. 

[IDO]

Longer term , the main difference between the gfs 6z and the 12z , is the 6z weakens the block to our East , where 12z keeps it 1055mb  .The longer we can keep that block to our East , the more time we will have for low pressure systems to dig South East and get an eventual retrogression  .

 

 

 

The problem is that at D16 we are still in this pattern (obvious caveats) and I am not sure we have that much time. The SSW/SW should be in process then, so the pattern maybe reset. With low heights over the NW I am unsure whether that would be a good starting point of another period of HLB. With the US probably favorite to get another cold pool. In the interim it is likely to be milder than cooler in this pattern.

 

In any case my interest will now be if we can get November as the warmest anomalous CET of the year. It is closing in (now +1.8C).

 

GEM a flatter version of the GFS at T186:  D10: 

 

Also keeping a milder pattern like the GFS.

Edited November 17, 2014 by i'm dreaming of...

[Cheshire Freeze]

The problem is that at D16 we are still in this pattern (obvious caveats) and I am not sure we have that much time. The SSW/SW should be in process then, so the pattern maybe reset. With low heights over the NW I am unsure whether that would be a good starting point of another period of HLB. With the US probably favorite to get another cold pool.

 

In any case my interest will now be if we can get November as the warmest anomalous CET of the year. It is closing in (now +1.8C).

 

GEM a flatter version of the GFS at T186: gem-0-186-2.png

 

Also keeping a milder pattern like the GFS.

The issue is you're (and you're not alone in this) taking the 7-14 day range as a given. I feel the NWP is maintaining the status quo in the extended range as a response to where we are in terms of the stratosphere as of now. You can see warming is enhanced with the 12z and as we progress over the course of the next week the modelling will slowly get a grip as to which path we go down. It's sort of a no-mans land at present but I'd wager this won't last too long one way or another, for better or for worse in terms of future cold prospects for the UK.

[BLAST FROM THE PAST]

theres no doubt steve very big swings from last night seriously feel this is going to drag on into december main feature being middle ground, cant see a zonal train setting up no time soon and cant see beasterly but i can see cooler surface temps with frost and fog.

 

thats ok suits me let the action commence because this is ideal for future developements.

 

if we could get this between the azores and scandi block se into europe it would be game on..... but tbh i was expecting a turn around hopefully tonights runs will revert back but got a feeling that the party poppers are going to have to wait a while longer yet.

 

but hey no zonal and more seasonal is still a step in the right direction.

ER

Saves me posting the chart.  ECM 240....I'm happy with the way that is going and something like that could lead to the game changer with that heading ESE imo, pressure from AZH coming in from behind linking to Scandi Heights and an increasingly cold E /NE'ly feed following on.  Lots of juggling for models to resolve but although pattern may develop beforehand, the wintry weather not likely to arrive pre-Dec   Now must knuckle down and top and tail lor it will be Spring soon, winter is coming and very soon...

 

BFTP

Edited November 17, 2014 by BLAST FROM THE PAST

[Snowy L]

All I see on the models is weeks and weeks of mid-lattitude blocking. The Atlantic lows just don't want to undercut.

[MR EXTREMES]

ER

Saves me posting the chart.  ECM 240....I'm happy with the way that is going and something like that could lead to the game changer with that heading ESE imo, pressure from AZH coming in from behind linking to Scandi Heights and an increasingly cold E /NE'ly feed following on.  Lots of juggling for models to resolve but although pattern may develop beforehand, the wintry weather not likely to arrive pre-Dec   Now must knuckle down and top and tail lor it will be Spring soon, winter is coming and very soon...

 

BFTP

but lets face it tonights outputs are rather depressing things certainly look likely to revert back to defult zonal.

dreadful charts so far.

i think to be fair were hoping for to much to soon.

 

gem 

ukmo 144

gfs 144

 

make of it as you will certainly looks like the models fast moving away from saturday evenings excitement thats 3 runs on the trot with back track.

we have more low pressure bang on the uk door but block slowly retreating east allowing an zonal attack but possibility is more stalemate at the moment.

[Ali1977]

I think we were all hoping for something early, definitely looks like we need to wait till December before any potential, if not mid December. This isn't a bad thing, at least by then the continent, arctic and SSTs will be much colder to assist any cold sourced weather.

[MR EXTREMES]

All I see on the models is weeks and weeks of mid-lattitude blocking. The Atlantic lows just don't want to undercut.

agreed its very frustrating as the ecm 240 this morning was a possible route to colder conditions this is turning into a major wild goose chase thats without model errors and what not.

 

huge scatter enormous to be honest we need lower heights to our southeast into europe 

[Polar Maritime]

Can we please stick to what the Models are 'showing', There is a hopes/thoughts thread open for the upcoming Winter.

Thanks, PM.

Edited November 17, 2014 by Polar Maritime

[IDO]

The issue is you're (and you're not alone in this) taking the 7-14 day range as a given. I feel the NWP is maintaining the status quo in the extended range as a response to where we are in terms of the stratosphere as of now. You can see warming is enhanced with the 12z and as we progress over the course of the next week the modelling will slowly get a grip as to which path we go down. It's sort of a no-mans land at present but I'd wager this won't last too long one way or another, for better or for worse in terms of future cold prospects for the UK.

 

Remember all the flailing about by the models, throwing in Greenland, Scandi and UK highs, were just the models not handling the situation. After 3-5 days of that, guess what GFS and GEM are now showing consistency with respect to a continuation of the repeating pattern. All those potential charts were just the figment of the imagination of the models and in fact nothing much is likely to happen apart from the cyclic synoptic pattern repeating. So yes I am now looking at the pattern and extrapolating from what I assume is the way forward. I do not see an undercut due to where the current upper ridge is:

 

 

Any trough disruption is more likely to lead to a a harmless upper level low somewhere south of the Med. The control and mean at D10 has good continuity:

 

 

 

Further evidence of the pattern now evolving in that direction with solid support now on the GEFS. Of course this is only my assumptions and I was wrong last week when I thought the Atlantic would barrel in, though that was more in hope than anything else, as I believe the disrupted PV is unlikely to keep us in a zonal flow for long unlike last year, so a reboot was my preference going forward. Lets see if ECM joins the consensus tonight.

[bobbydog]

All I see on the models is weeks and weeks of mid-lattitude blocking. The Atlantic lows just don't want to undercut.

 

 

but lets face it tonights outputs are rather depressing things certainly look likely to revert back to defult zonal.

dreadful charts so far.

i think to be fair were hoping for to much to soon.

 

gem 

ukmo 144

gfs 144

 

make of it as you will certainly looks like the models fast moving away from saturday evenings excitement thats 3 runs on the trot with back track.

we have more low pressure bang on the uk door but block slowly retreating east allowing an zonal attack but possibility is more stalemate at the moment.

 

 

Two contradictory posts there.

 

if we take the tropospheric models at face value, the first statement looks more likely.

 

 

however, i would think neither would be correct when we have this on the cards-

 

Edited November 17, 2014 by bobbydog

[knocker]

This has probably been posted before and I missed it.

 

 Environment Canada upgrades their Global deterministic, ensembles and regional models tomorrow at 12z.

[Captain Shortwave]

The GFS doesn't develop the jet cut back here but the UKMO looks more interesting than its earlier 00hrs run. I think the juries still out here because the UKMO does cut the shortwave south:

 

UW144-21.gif

 

If you get more kick north in the jet then the high will go further ne.

That low will probably drop into central Europe. The up side is the result would probably be a UK high which would at least bring some frost and fog.

As IDO has said, the models do seem keen on holding the pattern we have, this could again leave us in a rather stale south/south easterly with near average temperatures.

We just have to grin and bear it really to be honest. There are signs elsewhere that we could see some more interesting develop. Yet I've rather hold this stalemate than blast the Atlantic through whilst the Canadian lobe looks volatile as the results of low pressure properly crossing the meridian could be several weeks of wind and rain, something my part of the world would really suffer as there is already flooding in parts of this region.

[Dean E]

but lets face it tonights outputs are rather depressing things certainly look likely to revert back to defult zonal.

dreadful charts so far.

i think to be fair were hoping for to much to soon.

 

gem 

ukmo 144

gfs 144

 

 

make of it as you will certainly looks like the models fast moving away from saturday evenings excitement thats 3 runs on the trot with back track.

we have more low pressure bang on the uk door but block slowly retreating east allowing an zonal attack but possibility is more stalemate at the moment.

 

 

None of those runs reflect 'Default Zonal'? Can you show where you are getting this info from please?

 

I think while the Scandi High stays put, its not a terrible setup by any means. The Atlantic is completely shut off except that cunch of the Azores High that moves across

 

GFS +78hr is the furthest anyone should look right now, and even that is 'sticking your head out' at this unreliable time

 

 

I'm just sitting and waiting for now, its what best for everyone! 

 

SM

Two contradictory posts there.

 

if we take the tropospheric models at face value, the first statement looks more likely.

 

 

however, i would think neither would be correct when we have this on the cards-

 

 

 

Beat me too it and totally agree. Years of model watching has proven to me (2010 being a textbook example) that models don't handle SSW well until the last minute.

[ukpaul]

I seem to have clicked on the moans/ramps thread by mistake.

 

Anyway, I'm perfectly happy with this for the back end of Autumn.

 

 

Edit: Just seen that the 0.25 hadn't updated yet, so this is the earlier run.

Edited November 17, 2014 by ukpaul

[nick sussex]

A mixed bag of model outputs so far this evening. The GFS is okay, the UKMO better than this morning but the GEM and NAVGEM are dreadful with a flatter upstream pattern, thankfully the last two are hardly known for setting the world alight in the world of NWP.

 

We leave it to the deciding judge tonights ECM....

Edited November 17, 2014 by nick sussex

[Swave Snow]

Some real strange occurrences so far on the ECM in the first 72 hours the low in the mid Atlantic has come and gone twice so far.

 

At 96 h Atlantic looks like encroaching further than the 0z this morning

Edited November 17, 2014 by Swave Snow

[Man With Beard]

ECM T120 - signs that the Atlantic low is stalling against heights over UK/the east, and that it will split - will the southern portion of the split aid the creation of a cutoff Scandi HP?

Edit:answer = no, miles off!

Edited November 17, 2014 by rjbw

[bluearmy]

regarding strat/trop coupling in the modelling, i would think that the current models will do a better job than 4 years ago. they are all upgraded in this area re increased vertical resolution and model topping out.  i dont recall how bad a job they did in 2010 anyway.

 

starting to get some consistency now in the T96/T144 area.  be interesting to see if ecm is again intent on driving the jet se later on in its run.

[MR EXTREMES]

how many winters we seen this happen ecm 144 its sinking but only save an grace maybe is the azores will it beat the zonal attack you can see that the ecm has backed of bigtime 

[Swave Snow]

The block is back by 168 on the ECM 

Maybe not from the NH Profile

Edited November 17, 2014 by Swave Snow

[Nick F]

Interesting set of 12z GEFS postage stamps, only a few really going for a return of flatter/zonal Atlantic dominated flow past day 10, most members keep a highly amplified Atlantic trough to the west of the UK and block to the east pretty much to the end of the run. OK, this ain't gonna deliver any proper cold, but the prolonged WAA towards the arctic will sure put more pressure on the Polar Vortex which will have ramifications for the rest of winter as has been much discussed in the strat thread. A mild November maybe the ultimate price to pay for a cold winter.

 

As for 12z ECM thus far ... still holding back the Atlantic advance at t+168, probably as far as we can be confident of the models handling such a blocked situation IMO.

Edited November 17, 2014 by Nick F

[MR EXTREMES]

low pressure over the top of the scandi high so still pretty much a stalemate until the low moving ne flattens the pattern ok very much fi.

but to be fair still split vortex but aint there a ridge trying to build on the opposite side of the pole to us 

Edited November 17, 2014 by emotional rollercoaster