Model Output Discussions 12z 01/09/2016

[knocker]

The ecm is also developing the upper trough to the south west Note the classy Omega block

Edited October 1, 2016 by knocker

[daz_4]

I have to say it is very refreshing watching models now. There hasn't been a situation like this for a very, very long time and I'm just hoping this is a sign of thing to come and change of that frustrating pattern we've been stuck in for the last three years.

Anyway, this will be a first taste of winter with lot of rain and snow in the mountains. Highs next week will be around 5°C here which will be quite a shock since we hit 25°C today.

Well, I know this post is not UK related but I needed to share my excitement somewhere  

[Frosty.]

A very satisfactory Ecm 12z run with a large intensifying scandi high dominating the week ahead, especially across eastern and southern uk and then a uk based anticyclone building in making the first half of october generally pleasant across most of the uk and if the ecm is right, the whole of the uk settles down.

[legritter]

Evening all, great holiday touring cotswolds ,and some good weather and nice to see the possibility of a fair if not good start to October .

Nearly got stuck in floodwaters in Gloucester today ,looking at current charts it would be great to see high pressure bringing lots of dry settled weather which hopefully hangs around for a while and keeping that Atlantic at bay ,let's also hope that some of the charts can be repeated in a similar  vain this coming winter ,it was great reading g posts on net weather whilst on holiday but I could not reply ,some problem with bb wi fi ,great to have this forum around ,cheers all .

Edited October 1, 2016 by legritter
I said flood waters in Gloucester, it was fairly deep puddles but still fairly deep ,with so e hail in short bursts .

[phil nw.]

It still looking quite blocked across our side of the Atlantic with the Scandinavian high set to be a big factor for at least the next week or so.

Quite a wet day around these parts today but this could be the last appreciable rain for quite a while as pressure rebuilds across the country promising a return to quiet and dry weather for many of us.

The latest gefs 2m temps and rainfall graph for C.England

continue to show the generally dry and fine start to Autumn continuing through the first part of October.

 

 

 

Edited October 1, 2016 by phil nw.

[damianslaw]

Models continue to predict a very blocked pattern for the first part of October. Strong heights to the east and a very ineffectual jetstream. Longer term heights look like settling over the top of the country and to the north slightly - so eventually becoming near average, indeed perhaps slightly below.

[Frosty.]

There is no doubt what dominates the uk weather next week, a large powerful scandi high and the Ecm 12z ensemble mean shows that high extending its influence across the uk for the next week or so before it slowly weakens and drifts away e / ne and the question then is what happens next? The mean shows pressure slowly falling across the uk by early week 2  but the operational run shows a brand new high forming and building in over the uk which would extend the very benign pleasant spell for the BI as we continue to ease further into autumn...gently..

Edited October 1, 2016 by Frosty.

[knocker]

The anomalies are not in bad agreement tonight with the strong Scandinavian HP a not particularly anomalous trough and some ridging in the western Atlantic. And not forgetting the upper low to the SE! Thus the UK is in a col for a while until the trough to the west develops as we move forward into the ext. period and tracks SE with perhaps the main centre, and associated surface development a liitle to the south so perhaps some unsettled cooler weather for the south.

Edited October 2, 2016 by knocker

[knocker]

No significant change for the coming week from the GFS det. output this morning. The high pressure to the NE remains the influential factor bringing a dry, cool ESE flow, backing easterly as the high pressure drifts NE until the weekend when the scenario becomes more interesting.

By 00z Sunday we have the centre of the HP N. Scandinavia with a quite deep upper low to the SE and a developing trough mid Atlantic with the UK in a col. So the question is, how will this develop? Well according to the GFS we once again have some amplification with ridging over the UK and vitally intensification and development of the trough to the south west of the UK. This translates to quite intense surface low pressure tracking NE and bringing some wet and windy weather into the UK and heralds the introduction of low pressure dominating the Atlantic with the jet stream, not particularly powerful, running west-east into Biscay. Of course considering the time frame this remains a very speculative evolution.

EDIT

If this scenario had played out in the middle of winter we could have been looking at some significant snowfalls. Doesn't bear thinking about.

Edited October 2, 2016 by knocker

[knocker]

The METO is making a little more of the low to the south mid week

 

[knocker]

Not a complete surprise but the ecm is not going along with the GFS evolution at the end of the week. It starts to develop the trough but then reasserts the Azores HP It's all a bit messy so I feel a case of hanging fire.

[mb018538]

yes it looks a bit messy knocker, with no concrete sign of the later evolution. All in al looking very quiet and dry for the next week though.

[johnholmes]

Looking at the 3 anomaly charts I use and unclear is the main message! All 3 have altered emphasis more than once over the past 4-6 days so I sit on the fence for the time being. Perhaps slight indication of upper air ridging being the main influence but it is not clear just where that may come from. Also the position of the upper trough is not clear either.

 

[Captain Shortwave]

Well this week looks pretty dry and fine for most, though by the end of the week we will start to lose the anticyclonic influence somewhat.

The first element is the risk of cloud, drizzle or showers pushing in from the north sea was heights fall a little and we see cooler air moving in.

   

The next steps looks likely that we will see the cut off low to our south east will interact with the Atlantic trough which will be steadily moving east during the next weekend though there is uncertainty regarding this.

The ECM take

      

So looking fairly good for this week and turning quite warm for a time around midweek, then cooling off again with the risk of rain increasing from Friday onwards.

Into the middle of October I actually think this set up could very well repeat with heights amplifying to our west with the trough moving into central Europe so another easterly spell is very possible and the next time there could very well be a definite chill in the air (Not wintry yet though).

 

[knocker]

Looking a little closer at the EPS output this morning it does generate the upper trough to the south west and a general area of low pressure linking east across France and Germany to the other trough area at the beginning of next week. This could portend surface low pressure to the south for a short while.

Edited October 2, 2016 by knocker

[Daniel*]

A definite inclination to blocking. Intresting times. 

[Kieran]

Some chilly seasonal weather ahead of us according to the 12z GFS...

 

[blizzard81]

4 hours ago, Changing Skies. said:

A definite inclination to blocking. Intresting times. 

I remember that it was said that a strong positive nao in october would lead to a much higher chance of a negative nao during the following winter and vice versa. As a result, not sure I like that news.

[Frosty.]

Good news for those of us hoping for a largely fine and pleasant week ahead from the GEFS 12z mean which shows the strong scandi high still in charge by next weekend and only slowly weakening thereafter with a slack pressure pattern which still has a blocked look about it by week 2..there is no signal from the mean that the atlantic will fire up at all.

[SMU]

So the ECM has continues to develop the Easterly flow over the last 48 hours to be homing in on this set up at day 4

Now we have hit October the perfect winter synoptics will certainly deliver cool / colder upper air - 

The seasonal mean for England is about +6/7c & the ensembles point to a 'cool' pool at 0c / -1c 

so the upper air is around 7/8c below the normal - thats rare these days as October in more recent years has seen warm air in the UK

Nice !

 

 

[knocker]

I have to say the GEFS has been pretty consistent with regard to the upper pattern in this time frame. Would portend developing surface LP to the south producing some unsettled weather.

[Frosty.]

2 minutes ago, Steve Murr said:

So the ECM has continues to develop the Easterly flow over the last 48 hours to be homing in on this set up at day 4

Now we have hit October the perfect winter synoptics will certainly deliver cool / colder upper air - 

The seasonal mean for England is about +6/7c & the ensembles point to a 'cool' pool at 0c / -1c 

so the upper air is around 7/8c below the normal - thats rare these days as October in more recent years has seen warm air in the UK

Nice !

 

 

I can't get excited about dream wintry synoptics in October which would deliver diddly squat! 

November and especially Dec / Jan is a different story however!

[SMU]

Exciting 'NO'

interesting 'YES'

at day 6 Minus 6's over central / eastern europe

[Frosty.]

5 minutes ago, Steve Murr said:

Exciting 'NO'

interesting 'YES'

at day 6 Minus 6's over central / eastern europe

I agree, it's interesting but will have no bearing on the upcoming winter..and despite the dream wintry synoptics there is no hint from the met office of any unseasonably cool weather this month in their extended outlook, they indicate temps will be a little above average.

[summer blizzard]

Chart of the evening easily goes to the GEM which a month down the line may be making some pretty excited..

GFS and Euro have a similar outlook to day 10 (pressure a little weaker on the Euro) with a cool, anticyclonic flow from Friday so the west can probably look forward to a good durinal range.