Model Output Discussion 01/09/17

[MR EXTREMES]

57 minutes ago, knocker said:

Trending shockingly bad by day 10 with the Azores ridging north east.

2009 2010 believe it or not see Azores ridge through the UK the move up into Scandinavia although the real cold started with omega block in the Atlantic.

Until I see the Atlantic sweeping through the whole of the UK with blow torch SW flow then I'd be concerned.

But right now most of the activity is north so the Azores although pain in the butt can go from enemy to coldies friend.

Great seeing the Atlantic being held of further south.

[bluearmy]

Following on from the above post, the 18z op is not the first run of recent days to be very trough disruptive re the Atlantic. this is a broad theme which played out for the second half of spring and first half of summer. It would bring a coldish and potentially snowy winter to nw Europe.  

[JBMWeatherForever]

Like the increasingly southerly jet, with November continuing to look like a cold one on the whole. The Atlantic looks increasingly sluggish as well - An Easterly for late November perhaps?   

[knocker]

The high pressure currently situated to the south will slowly drift south east over the next couple of days.

Today, south of the Midlands and including Wales, will be dry, with little wind and quite a few sunny intervals so temps quite good. This will continue tomorrow albeit perhaps with a little more cloud. Further north and N. Ireland will be more cloudy with perhaps the odd patch of rain. But western Scotland will have a very wet day with some quite large rainfall amounts and some of this rain will spread south and east tomorrow. And it will be quite windy in Scotland as the large depression tracks east to be west of Norway by 12 Wednesday with Scotland in the south west quadrant and thus a north westerly.

By 12 Thursday the depression the slips south east into eastern Europe leaving an analysis with which we are all familiar. Troughs to the north west and the cut off low to the south west with high pressure ridging north east into the UK The strong thermal gradient running ENE just to the NW of Scotland.

Over the next 48 hours pressure from this area relegates the ridge ridge south west and allows a weak front to track south east across the country bring light rain to most.and generally introduce a tad cooler air.

From this point it gets a little more complicated. Under another bout of amplification the trough tracks east (not south east) and deconstructs creating another cut off low, and the Azores once again ridges north east but on this occasion all the way into Scandinavia leaving bonfire night dry with light winds  Thus by the beginning of next week we have the major trough in the Greenland/Iceland area with the associated troughs struggling to make progress south east across Scotland

This does eventually make it, facilitated in this endeavor I suspect, by the newly created trough to the south east. Over much of the UK during this period is influenced by relatively benign weather with temps varying around the average. The exception being western Scotland which could receive some quite significant rainfall totals.

Edited October 31, 2017 by knocker

[bluearmy]

4 hours ago, JBMWeatherForever said:

Like the increasingly southerly jet, with November continuing to look like a cold one on the whole. The Atlantic looks increasingly sluggish as well - An Easterly for late November perhaps?   

The updated ec46 is certainly not without interest - suspect the extended meto will give best guidance as to confidence in it. The predicted upper ridge in the Arctic n of the aleutians towards the end of the run indicates that current hemispheric patterns are not going to disappear as we head through December.

[knocker]

Although not surprisingly varying in detail the ecm is not a million miles from the gfs

 

[jvenge]

EPS weeklies is out. Quite a range of extremes on view from the control run, with some extreme cold and warm anomalies for Europe over the next month and not much time between them, either. At times considerably above average and at times considerably below. Not sure I buy into it, since it seems to move through the evolutions fairly quickly. 

It's worth mentioning that the mean of the 51 members is not so bullish and this suggests that although the control has some support, there are enough members not buying into the extreme options. Not able to see individual runs to see how they breakdown.

[memories of 63]

Purely going with my gut . I feel tht there's something different about this year.  HP seems to be further north in the Atlantic than normal and there are suggestions that  a ridge up to Greenlandor over to Scandi may beon the cards.

 

It may all be wishful thinking though

Edited October 31, 2017 by memories of 63

[blizzard81]

1 hour ago, bluearmy said:

The updated ec46 is certainly not without interest - suspect the extended meto will give best guidance as to confidence in it. The predicted upper ridge in the Arctic n of the aleutians towards the end of the run indicates that current hemispheric patterns are not going to disappear as we head through December.

Cheers BA. Any links to the pressure anomalies for each week?

[feb1991blizzard]

Genuine (snow potential) Northerly on the GFS 6z with disturbances, polar low alert even.

[bobbydog]

mostly dry, chilly, foggy, frosty for most of us for a while- 

 

with a very interesting finale-

 

 

and with still another 122 GFS runs until winter actually arrives, it could get even more interesting.... 

Edited October 31, 2017 by bobbydog

[bobbydog]

10 minutes ago, feb1991blizzard said:

Genuine (snow potential) Northerly on the GFS 6z with disturbances, polar low alert even.

not sure about a polar low, (you'll be quoted in the Express tomorrow!) but if charts like that keep coming, it'll put some smiles on the faces of us 'coldies'...

[feb1991blizzard]

2 minutes ago, bobbydog said:

not sure about a polar low, (you'll be quoted in the Express tomorrow!) but if charts like that keep coming, it'll put some smiles on the faces of us 'coldies'...

Just looked at the wiki definition and it does say they can form long horizontal temp gradients as well and the -45c isotherm is definitely very near to it.

[bobbydog]

10 minutes ago, feb1991blizzard said:

Just looked at the wiki definition and it does say they can form long horizontal temp gradients as well and the -45c isotherm is definitely very near to it.

not saying it won't happen but either way, the 06z puts europe in the freezer at the end and that would be good news for our winter. 

[jvenge]

I don't see anything to suggest that Europe goes into the freezer at the end of the 06z, even after looking at the ensembles. I can't imagine how it makes an ounce of difference to the UKs weather prospects come winter time either, even if it did show that.

Not bad consistency from GEFS out to T174.

 

[bobbydog]

4 minutes ago, jvenge said:

I don't see anything to suggest that Europe goes into the freezer at the end of the 06z, even after looking at the ensembles. I can't imagine how it makes an ounce of difference to the UKs weather prospects come winter time either, even if it did show that.

Not bad consistency from GEFS out to T174.

 

eh? 

thats most of western europe looking pretty nippy there, and its well known that if the near continent is cold, then if we get winds from an easterly direction, we have something to feed on.

never heard of the frequently mentioned "cold pool"?

[feb1991blizzard]

10 minutes ago, jvenge said:

I don't see anything to suggest that Europe goes into the freezer at the end of the 06z, even after looking at the ensembles. I can't imagine how it makes an ounce of difference to the UKs weather prospects come winter time either, even if it did show that.

Not bad consistency from GEFS out to T174.

 

Really, not even this?

[jvenge]

40 minutes ago, bobbydog said:

eh? 

thats most of western europe looking pretty nippy there, and its well known that if the near continent is cold, then if we get winds from an easterly direction, we have something to feed on.

never heard of the frequently mentioned "cold pool"?

Okay, nippy is doable I guess, but hardly unusual for mid November. By that time it will be the middle of November. I live in Eastern Europe. Cold pools don't plonk themselves here just waiting to be tapped into and outside of a few GEFS members, which is consistent with every run the past week or so, there is nothing unusually cold showing for Eastern Europe, let alone Europe.

 

44 minutes ago, feb1991blizzard said:

Really, not even this?

The surface temperatures, outside of the furthest northern reaches of Scandinavia, would be best described as a fridge set too low, not a freezer. That 850 anomaly, although will feel "nippy" as someone above described, are not freezer conditions..

Perhaps to those who take everything written here as gospel. The GFS and GEFS are not showing anything remarkably cold for Europe and certainly nothing to be described as freezer conditions. Attached are GEFS anomalies for the next 16 days. My deep cold anomaly over my country today might just take me below freezing in the early hours of the morning.

 

[bobbydog]

6 minutes ago, jvenge said:

Okay, nippy is doable I guess, but hardly unusual for mid November. By that time it will be the middle of November. I live in Eastern Europe. Cold pools don't plonk themselves here just waiting to be tapped into and outside of a few GEFS members, which is consistent with every run the past week or so, there is nothing unusually cold showing for Eastern Europe, let alone Europe.

 

The surface temperatures, outside of the furthest northern reaches of Scandinavia, would be best described as a fridge set too low, not a freezer. That 850 anomaly, although will feel "nippy" as someone above described, are not freezer conditions..

Perhaps to those who take everything written here as gospel. The GFS and GEFS are not showing anything remarkably cold for Europe and certainly nothing to be described as freezer conditions. Attached are GEFS anomalies for the next 16 days. My deep cold anomaly over my country today might just take me below freezing in the early hours of the morning.

 

well we ARE actually talking about mid november, so i don't see what the issue is. we are also talking about the far end of the GFS, which as we know, is highly unlikely to look anything like that by the time we actually reach that date. right now, its just a bit of fun and speculation... chill....

[jvenge]

10 minutes ago, bobbydog said:

well we ARE actually talking about mid november, so i don't see what the issue is. we are also talking about the far end of the GFS, which as we know, is highly unlikely to look anything like that by the time we actually reach that date. right now, its just a bit of fun and speculation... chill....

Quite chilled, but not in the freezer :-)

Some members here have quicker access to models than me. When I see posts here saying into the freezer, I patiently wait for my sources to update and then imagine my surprise when there are no freezer conditions or anything even remotely close to it. Luckily, I have a good access to the models and I'm not half bad at reading them, but for other members, which this thread does attract at this time of year, into the freezer, to put it mildly, would be better left to the ramps thread, since it has no basis in what the models show, even with very liberal subjectivity.

Anyway, I don't want to argue. The EPS weekly control shows something more interesting the second half of November for those looking for potential freezer temperatures :-)

[bobbydog]

4 minutes ago, jvenge said:

Quite chilled, but not in the freezer :-)

Some members here have quicker access to models than me. When I see posts here saying into the freezer, I patiently wait for my sources to update and then imagine my surprise when there are no freezer conditions or anything even remotely close to it. Luckily, I have a good access to the models and I'm not half bad at reading them, but for other members, which this thread does attract at this time of year, into the freezer, to put it mildly, would be better left to the ramps thread, since it has no basis in what the models show, even with very liberal subjectivity.

Anyway, I don't want to argue. The EPS weekly control shows something more interesting the second half of November for those looking for potential freezer temperatures :-)

i dont want to argue either but i should point out that my "freezer" post was regarding the very end of the GFS - just before the second half of november, in which you yourself mention "freezer temperatures"...

[weirpig]

Ensembles below  show qute a cool outlook as we head into November.  The OP keeps it cool then cold as the period ends. The Control on the other hand  ends up the same way however goes a completely different route to get there.   As it stands at the moments  typical November weather  cool and quite dry  Not to bad.

[bryan629]

Just to illustrate a trend that the models appear to be advertising,

Heres the ECM ang GFS at 192 as it looks like the trop vortex is setting up shop in its usual location west of Greenland and no doubt ready to fire up the jet stream. 

However, By 240 ECM and a little later with the GFS , this process is quickly halted as it is very evident below that (a) the trop vortex is been shunted across the pole to the Siberian side or (b ) it just gets ripped apart anyway

Either way it makes ridging into the vacant space a lot more likely and perhaps give our neck of the woods a good shot of an early bite of the cherry. We shall see !!

Its good to know something may be lurking in the woodshed so early in the season.. . 

[Cheshire Freeze]

1 hour ago, bryan629 said:

Just to illustrate a trend that the models appear to be advertising,

Heres the ECM ang GFS at 192 as it looks like the trop vortex is setting up shop in its usual location west of Greenland and no doubt ready to fire up the jet stream. 

However, By 240 ECM and a little later with the GFS , this process is quickly halted as it is very evident below that (a) the trop vortex is been shunted across the pole to the Siberian side or (b ) it just gets ripped apart anyway

Either way it makes ridging into the vacant space a lot more likely and perhaps give our neck of the woods a good shot of an early bite of the cherry. We shall see !!

Its good to know something may be lurking in the woodshed so early in the season.. . 

Important to stress we've been here many many times before with charts of promise 10+ days away. 

That being said it's something to keep an eye on as we progress into November. Personally I prefer early cold ala 2010 as Feb and March cold doesn't interest me. 

[ACCOUNT DELETED]

10 hours ago, knocker said:

The high pressure currently situated to the south will slowly drift south east over the next couple of days.

Today, south of the Midlands and including Wales, will be dry, with little wind and quite a few sunny intervals so temps quite good. This will continue tomorrow albeit perhaps with a little more cloud. Further north and N. Ireland will be more cloudy with perhaps the odd patch of rain. But western Scotland will have a very wet day with some quite large rainfall amounts and some of this rain will spread south and east tomorrow. And it will be quite windy in Scotland as the large depression tracks east to be west of Norway by 12 Wednesday with Scotland in the south west quadrant and thus a north westerly.

By 12 Thursday the depression the slips south east into eastern Europe leaving an analysis with which we are all familiar. Troughs to the north west and the cut off low to the south west with high pressure ridging north east into the UK The strong thermal gradient running ENE just to the NW of Scotland.

Over the next 48 hours pressure from this area relegates the ridge ridge south west and allows a weak front to track south east across the country bring light rain to most.and generally introduce a tad cooler air.

From this point it gets a little more complicated. Under another bout of amplification the trough tracks east (not south east) and deconstructs creating another cut off low, and the Azores once again ridges north east but on this occasion all the way into Scandinavia leaving bonfire night dry with light winds  Thus by the beginning of next week we have the major trough in the Greenland/Iceland area with the associated troughs struggling to make progress south east across Scotland

This does eventually make it, facilitated in this endeavor I suspect, by the newly created trough to the south east. Over much of the UK during this period is influenced by relatively benign weather with temps varying around the average. The exception being western Scotland which could receive some quite significant rainfall totals.

That rainfall accumulation chart above clearly shows the mild, moist SW'ly winds will be soon returning, so Western Scotland in the firing line but also very wet across SW Ireland and to a lesser extent West Wales (that'll probably come from persistent steady rain which could get stuck for days like we had last week here in South Wales). 

Edited October 31, 2017 by DJ RY