Model Output Discussion - Winter arrives

[sheikhy]

8 minutes ago, carinthian said:

Just a follow up from my post earlier this morning. The GFS 06h run showing the possibility of some snow across NE of the British Isles next Friday morning ( north of the Humber Flue ).This is a similar profile indicated by the UKMO extended shown yesterday. Whether any snowfall is transient or grinds to a halt is still in the balance. However cold blocking is now becoming more prevalent in some of the runs.

 C

Yup moving towards ukmo and ecm from yesterday 12z!not sure if ecm still has the snow event though!!

[Ali1977]

The Control is about to attempt the Scandy high too 

[Lukesluckybunch]

Just now, Ali1977 said:

The Control is about to attempt the Scandy high too 

yes we will see if it can make it properly!my guess is it  wont but i hope i am wrong.

[Tim Bland]

Quite remarkable to see so much of Europe snow covered so early in the season….

[sheikhy]

Control and mean much im

3 minutes ago, Tim Bland said:

Quite remarkable to see so much of Europe snow covered so early in the season….

Control and mean much improved on 06z!!has the ecm still got the snow for next friday mate?!!

[That ECM]

On 27/11/2021 at 11:10, Ali1977 said:

The Control is about to attempt the Scandy high too 

Indeed.

[northwestsnow]

The diving low next week has implications for any ridging up from the Azores ..

 The Sharper and more energy the better,we want the Azores high pushing as far north as possible (behind the diving low )

I'm going to  say GFS was first to pick this up,or this potential signal up..

All eyes 96- 144 tonight...

Edited November 27, 2021 by northwestsnow

[Griff]

@jules216 posting some very tantalising charts this morning...

[MATTWOLVES 3]

Great start to early Winter here...falling snow and a slight covering.

I'm starting to like the prognosis also,it's always good too see the ops showing some colder

evolutions,but we are seeing a fair number of ens also hint at various cold shots further ahead!

So for me I think the risks are now growing! I'm not gonna commit on robust scandy Heights or the like,but sliders and regular pm airmasses look a growing trend....so we can't rule out saying the S word now can we?

Actually we can...its already snowed heavy here on the 27th November....so sing it till your hearts content...its the weather and it doesn't give a dam

0z ens by the way.

 

Edited November 27, 2021 by MATTWOLVES

[Battleground Snow]

3 minutes ago, Griff said:

@jules216 posting some very tantalising charts this morning...

I'm just hoping the GFS isn't overplaying the mjo influence in phase 6 and 7.

[Nick F]

GFS certainly persistent in trying to build heights NE over Scandi in the medium-long range. EPS cluster support  beyond day 10 for height rises to our NE too and trough over Europe.

A good deal of uncertainty with regards to MJO progression, gets to P6 but will it make to P7. EC just about gets there, coming more round to the idea of colder phases than previous days. Often it is too mute with the signal, even in La Nina when the signal can be weak.

Next weekend could see height rises in the GIN corridor then perhaps extending into Scandi. The models may try to sink the block too quickly IMO and bring in zonality after day 10. Be wary of that. But that's not to say it won't happen and we end up on a stormy westerly path to mid-Dec.

Edited November 27, 2021 by Nick F

[northwestsnow]

2 minutes ago, Battleground Snow said:

I'm just hoping the GFS isn't overplaying the mjo influence in phase 6 and 7.

It's possible...

I always remember one of my contemporaries saying scandy highs have a habit of appearing from nowhere ..

Could it happen December 2021 ?

 

 

[nick sussex]

The shortwave energy you see ejecting from nw day 8 into 9 needs to head more se rather than south towards Iberia .

This will help support the high over Scandi and help to draw colder uppers from the east .

Still two runs in a row with the same trend from the GFS.

Lets hope for a third this evening.

[Methuselah]

Well, to my untrained eye (and taking into account both the Met Office's monthly and anomaly forecasts), any HP to our east will be transient. Though one can never entirely rule out wintry precipitation, freezing fog might be the main hazard?

    

    

    

[Ali1977]

Control is going out of control

Although it has some support 

Edited November 27, 2021 by Ali1977

[johnholmes]

This link makes interesting reading for the conditions in the Peak District higher areas this morning, along with some web cam photos

 Buxton Weather – Live Weather in Buxton Derbyshire, UK

WWW.BUXTONWEATHER.CO.UK

---

Buxton Weather – Live Weather in Buxton Derbyshire, UK

 

[Griff]

2 minutes ago, Ali1977 said:

Control is going out of control

Although it has some support 

Goes to show how much the outlook has changed since a week ago here / the previous thread. 

I'll concede, it could well look very different again by next weekend but fascinating! 

[Eagle Eye]

If heights were to build strong enough towards Greenland I could see a more easterly flow eventually happen but it's unlikely (although on the models at the moment)

Edited November 27, 2021 by Eagle Eye

[Catacol]

49 minutes ago, Griff said:

@jules216 posting some very tantalising charts this morning...

Reckon that ECM chart fits the shape of things Griff. I think GFS is a stretch…..but the weather can make fools of all of us at times so who knows…….

[Anthony Burden]

31 minutes ago, Nick F said:

GFS certainly persistent in trying to build heights NE over Scandi in the medium-long range. EPS cluster support  beyond day 10 for height rises to our NE too and trough over Europe.

A good deal of uncertainty with regards to MJO progression, gets to P6 but will it make to P7. EC just about gets there, coming more round to the idea of colder phases than previous days. Often it is too mute with the signal, even in La Nina when the signal can be weak.

Next weekend could see height rises in the GIN corridor then perhaps extending into Scandi. The models may try to sink the block too quickly IMO and bring in zonality after day 10. Be wary of that. But that's not to say it won't happen and we end up on a stormy westerly path to mid-Dec.

Hi Nick,still very much in the air one might say but encouraging signs are there for an East v West  battle 

Lots to hope for in a very uncertain up and coming winter /La -Nina /EQBO/MJO.

 

[SqueakheartLW]

Just looking at the GFS Extended run for today to see if there are any potential cold patterns appearing for Christmas Day.

I have picked out the members that have a pattern that is either cold or has potential to be cold if the parameters are somewhat different on the day.

Note at this stage I am more focused on the pattern itself rather than what the 850hpa temps are showing

P01

Although the uppers suggest mild here it is high pressure dominated so could contain surface cold. Also note the general continental feed as well. Maybe if we get this kind of pattern it could end up colder than these charts would suggest

P07

A quite cold northerly feed here on these charts. Would no doubt be a cold day. Could end up with even colder uppers come the day if we get a pattern similar to this one

P14

My first proper easterly chart showing here. Could upgrade somewhat to more of a beasterly come the day if this is the route we head down

P15

A bit more of a transient colder snap here, quite similar to our recent patterns and one that is quite possible if we stick to the mid Atlantic ridge scenario.

P16

Really a colder version of the above and not totally out of the question either for Christmas Day

P17

Although showing mild uppers this is more about where the high pressure is sitting more than anything. Very likely to see cold surface feed from the east here and look at all that cold air waiting further to the east too

P18

Again more about the location of the high pressure and the continental feed rather than the uppers. Could be a very cold pattern if we get colder uppers in over Europe before this pattern emerged for the big day

P22

A cold anticyclonic pattern for Christmas Day looks a real possibility. Many of the extended members have high pressure close by to the UK on the big day

P23

Another dry member for the big day and with the uppers not exceptionally mild then frost is very likely. Could end up even colder if we can trap a bit more cold in at the surface

P27

Cold and anticyclonic again. A common theme showing here it would seem.

P28

Probably the most unsettled of the colder options. A marginal snow situation here with these current charts but it wouldn't take much to produce a preceding colder pattern before this to get a more definite white Christmas here

P29

Just shift this one a bit further west and we'll be game on here for a cold day with snow showers a risk in the N especially

[Cleeve Hill]

1 hour ago, Nick F said:

GFS certainly persistent in trying to build heights NE over Scandi in the medium-long range. EPS cluster support  beyond day 10 for height rises to our NE too and trough over Europe.

A good deal of uncertainty with regards to MJO progression, gets to P6 but will it make to P7. EC just about gets there, coming more round to the idea of colder phases than previous days. Often it is too mute with the signal, even in La Nina when the signal can be weak.

Next weekend could see height rises in the GIN corridor then perhaps extending into Scandi. The models may try to sink the block too quickly IMO and bring in zonality after day 10. Be wary of that. But that's not to say it won't happen and we end up on a stormy westerly path to mid-Dec.

Is all that cold air in Scandi helping to promote a Scandi block ? 

[SqueakheartLW]

BOOM !!!

GFS Extended P07 at +504 hours away

I'll take this one please and shift it a tiny bit further north

[mushymanrob]

1 hour ago, Battleground Snow said:

Those charts never showed the mid Atlantic ridge until after the ops had for many runs

 

1 hour ago, tight isobar said:

But the only scenario in which they do is on these Synoptics-@easterlys...opS always sniff the easterly component 1st .. @ usually.

Youre both missing the point.... The ops show all kinds of FI options, some of which will identify an emerging pattern first. And its true the Anomalies dont always show an emerging pattern first, but they do show an emerging pattern most accurately. For example, just go to day ten, t240 and see how many different options there are, one of which is likely to be right, but which one?... the one (or more) closest to what the Anomaly mean charts suggest will always be the most likely to verify.

Now im not saying that there wont be a scandinavian high developing, im saying that as things stand, there is no scandinavian high on these charts for this timeframe, so until there is, the current ops showing it will most likely be proven inaccurate.



 

[Methuselah]

Well, I can't see anything in the GEFS 06Z ensembles that gives any convincing signal for a dominant Scandi HP setting up. A fleeting affair, perhaps?