Model Output Discussion 1st Nov.2013

[garbagebags]

such terrible model runs lately. all they keep showing us is autumnal weather in the short to medium term. anyone would think it was autumn!

its so disappointing the way, at longer range, they consistently keep showing us high pressure blocking, in the form of a massive aleutian high and a mid atlantic ridge in the run up to winter, keeping the PV from gaining strength.

who would want that??

next thing you know, they will be showing us wintry weather..... in winter!!!...... unbelievable!!

 

if we dont get heavy snowfall in november (autumn...) then winter is over!

 

(unless of course, you are fully aware that winter starts in december and the charts (and all the other signs, like eurasian snow cover for example, are showing potential for a winter of epic proportions....)

so let me get this right. November is Autumn. We are in Autumn. Yeah. I think you made that quite clear...

[tight isobar]

There appears to be unfortunately, some postings, that are not topic neither/nor, but deliberated digs. I hope this resolves. Winter relate, please. Or refrain from personal gripes..(uncalled). There are other forums to my info for such unadulterated!!!!

[Barry12]

GFS t-168 is much better on the 18z compared to the 12z, the cold arrives quicker and covers much more of the UK.

 

Edited November 10, 2013 by Barry95

[Tamara]

I think the last couple of posts have summed things up well  We are looking to end the autumn period on quite an encouraging note I think if we take into account not the recent years with the colder high latitude blocked patterns that have surprised many of us (maybe? )and spoilt us in equal measure, but on the basis that at face value this late autumn and early winter season is not  encouraging at all with the background patterns and does not lend itself to such a favourable default scenario.

 

We have a strong organised and, by definition, cold vortex and whilst it is typical for the vortex to be strengthening at this time of the year, the jet stream trajectory shows all the hallmarks of the amplification that has been AWOL in many other of the pre 2008/09 years that have characterised a stable and early dominant vortex. There have been autumn seasons (f.e most recent 2006) that have shown the same, apparently, stable very flat vortex over the pole, and with polar maritime air in the wake of vigourous low pressure systems failing to push far enough south beyond the Scotish borders. However this year we are seeing already a different shape to the pattern to then, with the main centres of vortices shearing from west to east across the pole, courtesy of a hugely amplified pattern on the other side of the arctic which is unlikely to produce the classic blocking of 09/10 or early winter 10/11 and also the classic patterns of late winter and Spring this year - but they suggest an increasingly colder mobile pattern to follow what has been a warm autumn up to now, and in that sense we can think of other autumns with highly amplified patterns that have produced similar decent earlier cold snaps/spells, and led onto much better and longer lasting things later in the winter.

 

An atlantic ridge in the western/central atlantic, which is a consistent hallmark of much of the current modelling, is a good thing to see at this time of November on the basis of what the background factors suggest. Better that, than a flat Pacific/US/atlantic jet stream that has no 'boulder' as a dam in midstream to deflect and fracture the conveyor belt stram of low pressure.

 

Not much can be gleaned from the EPS ensembles which only go out to a week away, other than the fact that whilst the jet stream is strong, quite a few solutions suggests that the Azores High will draw west thereafter, and dig troughs southwards and eastwards - which is exactly what we want to see in an otherwise mobile westerly pattern.

 

Edited November 10, 2013 by Tamara תָּמָר

[radiohead]

Looking a bit flatter on the 18Z GFS out to 180 hours. We'll see what happens in FI, but nothing too inspiring up to this point.

 

[Barry12]

T192

 

[Gaz1985]

Strong pressure pushing down on us, and in the medium term not looking good for those wanting bitter cold and lowland snow 

 

Edited November 10, 2013 by chionomaniac
Removed irritating smiley.

[alexisj9]

Storm of the century in FI GFS, those isobars over Greenland have formed a solid white line

Well thank-goodness that is probably not going to verify.

[Purga]

GFS 18z reinforcing the mild theme and showing some very mild periods in FI this time.

 

 

Really looks like an uncertain picture to me with wintry stuff only for the mountains of Scotland at times.

[Panayiotis]

In the last 2 days, ive made my own 'archive' for the last 8 runs from the CFS between the 20th and the 25th. Astonishing results and the consistency in showing something colder is amazing, as Steve says this is the period which needs watching! 

 

I think something colder than average will arrive with us, but how cold and long is up for debate!

PS. Over the next few days I will add the CFS runs to see if the trend becomes clearer!

Edited November 10, 2013 by Panayiotis

[radiohead]

GFS 18z reinforcing the mild theme and showing some very mild periods in FI this time.

 

 

Really looks like an uncertain picture to me with wintry stuff only for the mountains of Scotland at times.

 

 

It's worth remembering, that back on this day in November 2010, this is what FI looked like on the GFS :

 

 

And this of course is what Nov 25th really looked like when it came around :

 

[StretfordEnd1996]

It's worth remembering, that back on this day in November 2010, this is what FI looked like on the GFS :

 

 

And this of course is what Nov 25th really looked like when it came around :

 

Good find! But really though in all seriousness, 2010 was a very very unusual event. In realistic terms, the model outlook isn't showing much in the way of widespread cold. 

 

In my opinion, nothing like widespread cold on the horizon with these runs, but then again I can't understand why some folk would say these charts are very mild looking. 

 

Things can change, but at the moment, it's just looking seasonal 

[radiohead]

Good find! But really though in all seriousness, 2010 was a very very unusual event. In realistic terms, the model outlook isn't showing much in the way of widespread cold. 

 

In my opinion, nothing like widespread cold on the horizon with these runs, but then again I can't understand why some folk would say these charts are very mild looking. 

 

Things can change, but at the moment, it's just looking seasonal 

 

I'm in no way comparing this year to 2010 of course, just pointing out that by looking at FI on the GFS back then there was no indication of the type of severe cold and snowy weather that was in store. Sometimes when looking at FI on these models it helps to remember how the output is often way off the mark.

Edited November 11, 2013 by radiohead

[Purga]

I'm in no way comparing this year to 2010 of course, just pointing out that by looking at FI on the GFS back then there was no indication of the type of severe cold and snowy weather that was in store. Sometimes when looking at FI on these models it helps to remember how the output is often way off the mark.

Absolutely and that's why I said in my post that it "really looks like an uncertain picture to me"

 

I would dearly like to see a severely cold pattern develop but I don't think it looks likely right now.

 

 

 

[swfc]

Better run on the oz with regards to the position and movement of the high pressure all be it sits in situ over the uk in fi.Jet seems to have gone on one lol but still interesting signs looking at the nh charts ete.Big swings in the mo atm which could by the look of it finish anywhere!!!Also eastern europe looks good for cold and an increase in snow cover.Mr murrs call for a cold outbreak "be it brief"on the 21st may not be far off the mark atm???

Edited November 11, 2013 by swfc

[shaky]

Much better charts this morning totally agree swfc!!!compared to the 18z last night and ecm 12z!!now we just need the ecm to get back on board and we shall have a full house again.

[snowangel32]

Hi could someone plz explain to me why the morning charts look better i am still learning but to me high pressure is slap bang over the uk for almost all the run apart from the 20th. Is it the position of the high wich is better.

[swfc]

Hi could someone plz explain to me why the morning charts look better i am still learning but to me high pressure is slap bang over the uk for almost all the run apart from the 20th. Is it the position of the high wich is betteR

Hi.The position and strength of the high is better orientated yes.Ideally we want the high further north towards greenland or north east into scandinavia.Its trending in the rite direction and if your following the mo try and use the northern hemisphere charts for a clearer look.If you go on the archive charts and look on november-december 2010 you will see some good examples of blocking ete and how the movement of the high pressure changed the weather type during that weather event.

Edited November 11, 2013 by swfc

[snowangel32]

Ok thx for the help. One thing that even i can notice is a change is coming, exciting times ahead.

[shaky]

Ok thx for the help. One thing that even i can notice is a change is coming, exciting times ahead.

its amazing how just a few days ago people on this thread were saying there is no sign of cold weather on the way and novemeber is going to end up being very mild.well within the last couple of days the models have done a nice flip out of nowhere and now we are staring at a potential cold and hopefully snowy snap within the next two weeks. Just hope the ecm does a turnaround this morning.

[swfc]

Much better ecm at 192 hrs altho the high could topple or slip south .eitherway an improvement already today on both runs!

Edited November 11, 2013 by swfc

[Mark Neal.]

An improvement on the ECM 00Z, high better orientated. Will the high slip NW towards Greenland, or eventually topper over UK?

 

168hrs.

 

192hrs.

 

216hrs.

 

Uppers do gradually get colder through the run, with last few frames showing, -4c across northern england and colder uppers into scotland.

Edited November 11, 2013 by Mark N

[Ian Brown]

I think on the face of it at the moment there is the possibility of parts of the UK being on the cold side of the PFJ for a time, but there isn't anything to suggest High Latitude blocking, with general factors seemingly against this happening. The negative anomaly does seem to persist over Europe though hence the GFS is settled in FI.

[swfc]

Good start to the day and ecm is a big improvement on last night.Great output atm and all to play for imo.The jet is heading south and the nh charts still loaded with potential!!

[swfc]

I think on the face of it at the moment there is the possibility of parts of the UK being on the cold side of the PFJ for a time, but there isn't anything to suggest High Latitude blocking, with general factors seemingly against this happening. The negative anomaly does seem to persist over Europe though hence the GFS is settled in FI.

Morning Ian.Yes on the current output be it fi you are probably correct ie gfs and the high being in situ over the uk giving a settled outlook.The interest i think is in the subtle changes in the mo over the last few days ete and where it may head in the next few weeks.Im certain no one is expecting anything exceptional but something of a down turn in temps ete.