Model Output Discussion - early October

[Mapantz]

In my slim experience, the GFS has always had a tendency to throw up those scenarios at the back-end of a run when the polar vortex is forecast to strengthen and trop/strat coupling begins to take place.

[Allseasons-Si]

3 minutes ago, Mapantz said:

In my slim experience, the GFS has always had a tendency to throw up those scenarios at the back-end of a run when the polar vortex is forecast to strengthen and trop/strat coupling begins to take place.

Quiet true pantz

but is there anything wrong with posting charts what is being shown in the NWP?(numerical weather patterns) 

IE:- the gfs

the ecm doesn't show such scenario and we talk about this all the time to fathom out what is going on because when was the last time these both models ride in tandem...never

ok i get it that come nearer the time both of the models are inaccurate but we look for trends

is the gfs right or the ecm?

the gfs is showing cold that we want...yes,but i did state that the ecm needs to come on board,if not,we take it on the chin

as for the trop/strat,it's not my forte but i do have some understanding in that category but not much

i do not come across as a one sided person to cold but a balanced one,if the charts show cold,i will post them

  

 

[Mapantz]

8 minutes ago, Allseasons-si said:

but is there anything wrong with posting charts what is being shown in the NWP?(numerical weather patterns) 

Nope -  As long as there's no incessant ramping (which is fine in the other thread) then it's all good!

[Allseasons-Si]

And the control is a screamer,that shortwave at 240hrs is more pronounced N of Iceland than the gfs 18z hence the better northerly outbreak

which then leads to this.

 

 

[Allseasons-Si]

There isn't many members left north of the 0c isotherm is there.

Two days ago.

850 temps latest from gefs ens

today

two days ago

the trend over the last couple of days (as it stands) has trended to cooler/colder conditions from late next week as you can see above,more and more members are trending colder with quiet a few showing the -5 isotherm or below.

 

 

 

Edited October 15, 2019 by Allseasons-si

[JBMWeatherForever]

Strengthening signs of an early onset of winter by late October.   

[knocker]

The North Atlantic 500mb and surface analysis for midnight

The rain associated with the frontal system currently crossing the country is orientated west Scotland > north Wales > central southern England at the moment and will continue to track east and clear eastern England by midday. It will linger over eastern Scotland and some more rain may ingress the far south east later as a wave forms on the cold front. Sunny periods behind the rain belt with perhaps some showers in western regions.

Once the rain clears it will be a dry and clear night for most with the odd mist/fog patch in the north and east but the showers will become more frequent and heavier in western regions as the Atlantic low drifts closer.

The drift east continues tomorrow and with the occlusion and troughs in the circulation the showers will become more widespread, albeit still concentrated in western regions, and there could well be hail and thunder in the mix.

By Friday the low is over the country as the subtropical high zones amplify but note the nor'easter tracking north along the eastern seaboard. Thus a day of sunshine and heavy showers, particularly in the south and west

,A not dissimilar day on Saturday as the amplification continues apace and the trough over the eastern seaboard drops into the western Atlantic

The pattern continues to evolve to the west on Sunday resulting in a shift of the orientation of the UK trough. Still fairly unsettled with heavy showers but more concentrated to the south,  More persistent rain may effect the far north courtesy of another little wave

 

 

Edited October 16, 2019 by knocker

[knocker]

So this is the position by 1800 Monday as the trough is relegated south and a ridge builds north east across the UK

Over the next couple of days the Atlantic trough deconstructs as the Bermuda high amplifies into into Greenland and this is the position on Wednesday according to the gfs. Best left here as we noe well into the unreliable zone without the GEFS available

Edited October 16, 2019 by knocker

[knocker]

In the 7-12 period  the GEFS mean has trough disruption in the western Atlantic resulting in the subtropical high ridging into Greenland with the TPV/trough Franz Joseph.and thus a WNW upper flow across the UK. Portending continuing unsettled with temps around average or a tad below. But this period is far from resolved

 

Edited October 16, 2019 by knocker

[knocker]

The ecm through 168, 192

Still unsettled but very much with a N/S bias and the trough disruption very apparent

Edited October 16, 2019 by knocker

[joggs]

6 hours ago, JBMWeatherForever said:

Strengthening signs of an early onset of winter by late October.   

Explanations or proof please?

[Frosty.]

16 minutes ago, joggs said:

Explanations or proof please?

Not a bad looking GEFS 0z mean for those of us hoping for a very early Arctic shot later next week..which includes me!!❄

 

Edited October 16, 2019 by JON SNOW

[Yarmy]

18 hours ago, Yarmy said:

While the selected GEFS members above are probably too extreme, the trend towards greater amplification into Greenland and an increasingly negative AO can be seen on the ECM 0z mean for the past 3 days:

13th Oct T240

14th Oct T216

15th Oct T192

 

The height profile over Western Europe is largely unchanged though.

Just to add in today's update as the trend continues:

16th Oct T168

 

[MR EXTREMES]

indeed some eye candy today.

i think one background signal thats been extremely telling is the southern oscillation index/SOI atmosphere very el nino even though neutral enso.

hurricane season also churned up the atmosphere what with flatlined solar activity certainly brings a little bit of a 09/10  type set up.

of coarse might sound like an evil knievel ramp,

  and yes things can change,

but any form of block out to our west or northwest will aid in further developments especially first part of winter.

or could be back end winter like 2008.

but the models are gaining momentum on the idea gem also different still possible cold shot.

although i tend you wait for the ecm to bring it to the 72hrs point then confidence grows further.

we shall have to wait and see,

but i remember the gefs ensembles from winter 2010 and the cool down was slow and steady decline.

seems to be showing similar in the last few runs gem gfs gefs and ecm to a point. 

AND THEN YESTERDAYS........

 

[knocker]

The 5- 10 EPS mean illustrates the amplification and trough disruption in the Atlantic with the TPV/trough in the vicinity of Franz Joseph and this a upper north westerly flow over the UK portending unsettled but with very much a N/S bias although I'm reluctant to use that word in this thread. Temps around average. Of course within this pattern there may well be the odd transient northerly as systems track east, In the ext period the pattern adjusts east with the upper flow abating somewhat and continuing to become less unsettled with heights building, albeit retaining the  N/S split. Temps a tad below average.

To paraphrase Mark Twain. reports of Autumns early demise are greatly exaggerated

Edited October 16, 2019 by knocker

[Methuselah]

A couple of interesting-looking scenarios, from today's GFS 00Z:

At T+156:           

And at T+255:    

And, judging by the relative closeness of the Operational and Control runs, there's a fair chance that both could happen, to some degree:

                         

                         

Still too warm for anything widespread in the way of snowfall, but conditions still look good for some beefy convection -- owing to the warm SSTs surrounding the UK?

[Frosty.]

The Ecm 0z ensemble mean certainly indicates an Arctic shot of some description later next week, indeed more so than it did yesterday!

[weirpig]

Gfs  6z Following the trend of rises towards greenland   quite a blocked profile  

[shaky]

7 minutes ago, weirpig said:

Gfs  6z Following the trend of rises towards greenland   quite a blocked profile  

Dont like that low in the atlantic!!!want that further west which means more ridging in the atlantic or as slack as possible to undercut the greenland high!!craving a cold snap now lol!

[weirpig]

Just now, shaky said:

Dont like that low in the atlantic!!!want that further west which means more ridging in the atlantic or as slack as possible to undercut the greenland high!!craving a cold snap now lol!

Yes and me  getting to the time of year.    I agree its not as good as previous runs  however it wont look like that at 0z   all im looking for is the general pattern   and models do seem to agree on a more blocked Atlantic going into next week  

[shaky]

35 minutes ago, weirpig said:

Yes and me  getting to the time of year.    I agree its not as good as previous runs  however it wont look like that at 0z   all im looking for is the general pattern   and models do seem to agree on a more blocked Atlantic going into next week  

Yup and one thing is for certain the blocking around the arctic and hardly any pv at the moment is not normal for the end of october!!could this be the winter we been waiting for!!i damn hope so!!

[coldwinter]

4 minutes ago, shaky said:

Yup and one thing is for certain the blocking around the arctic and hardly any pv at the moment is not normal for the end of october!!could this be the winter we been waiting for!!i damn hope so!!

It really isnt uncommon to have blocking around the arctic towards the end of October. Long way off winter yet, what happens in the next 6 weeks in the strat is what we want to watch, amongst everything else. 

[Jordan S]

As another person has mentioned southeast England may turn wet this evening probably to the southeast of London giving an additional few mm's but the bulk of the rain likely remaining through the channel and Northern France but always some degree of uncertainty with these developing waves as always.

Tomorrow looking very unsettled with sunshine yes but also blustery perhaps thundery showers some areas may clock quite a bit of rainfall as these will be pretty frequent in places a few places perhaps remaining mostly dry I'm using the arome but this illustrates how the rest of the UK will be throughout tomorrow

Friday looking similar but the focus of heavy showers more and more for southern and western areas there may be more organised bands of rain moving through particularly early Friday. Weekend looking pretty showery but turning drier in the North winds will start to ease and even in the south by Sunday the showers should begin to die away with a decent end to the weekend so not a washout for most but perhaps still very wet for certain regions at times. Improving next week for a time atleast.. 

[knocker]

Current sat

 

[mb018538]

Day 10 clusters:



Atlantic looking quite blocked.