Model Output Discussion 1200 hrs 30/09/14

[SMU]

Morning-

 

Finally the GFS arrives at the party- & for those who persist with the GFS anaomlies etc saying nothing is changing - that couldnt be further from the Truth-

 

So remember the comment last night regarding the GFS will correct West with the American Low-

 

Well this is the 06z 144

http://modeles.meteociel.fr/modeles/gfs/runs/2014102906/gfs-0-144.png?6

 

& heres yesterdays 12z for the same timeframe

http://modeles.meteociel.fr/modeles/gfs/archives/gfs-2014102812-0-162.png?12

 

Note the shift west- from the southern tip of greenland yesterday to NE canada today.

 

 

Also, no change????

 

Hers tomorrows Theta E 850 charts.-

http://modeles.meteociel.fr/modeles/gfs/runs/2014102906/gfs-6-24.png?6   note the plume of +40c over the UK

 

now for just 5-7 days away-

http://modeles.meteociel.fr/modeles/gfs/runs/2014102906/gfs-6-120.png?6 A reduction to +22c & then day 7

http://modeles.meteociel.fr/modeles/gfs/runs/2014102906/gfs-6-168.png?6 Getting down to 10c.

 

 

Autumn / Winter is on its way- make the most of the next couple of days if you see the warm sun...

 

S

[IDO]

^^^^ I don't believe anyone has said nothing is changing. There has been a clear signal for a return to more seasonal weather. Clearly October will be an unusually warm month, CET +1.4c at the moment. November will lose the repeating meridional flow in all likelihood, though the initial slack westerly flow will allow transient ridges and troughs; Nov 5th-6th an instance of this, where we get a colder upper flow. Where the jet settles is not certain yet, but signs are that it will return slightly  further north in FI allowing closer to average temps in the south:

 

D12 mean:  Though high uncertainty: 

 

D12 on the GFS Parallel:   D16: 

 

So we get a very November like cool spell mid next week before temps return to close to average. ECM D10 mean shows standard November weather:

 

 

 

Though after D10 the mean suggests a split in the ensembles ( same uncertainty that is showing in the GEFS): 

 

No consistency with regard to the PV movement or it becoming more organised in FI, apart that it is increasing in intensity rapidly from its current state to the end of FI:

 

Parallel Current:  Parallel D16:  old GFS: 

 

The AO index confirms early November as a period where the PV goes strongly positive, the afore mentioned pattern change, but hints that it may move downwards afterwards: 

 

Its a case of how this change develops and whether in the longer term it will benefit the UK for cold.

Edited October 29, 2014 by i'm dreaming of...

[knocker]

A good post ido. I agree nobody has said nothing was changing and I thought I was clear about that with my earlier post re. the ECM anomalies. Actually the GEFS ens temps are quite interesting.

Edited October 29, 2014 by knocker
To remove long quote.

[Polar Maritime]

I have just had to deleted a post, Can we please keep to topic. There is always the pm facility to ask personal questions.

Many Thanks, PM.

[No Balls Like Snow Balls]

Feeling very chilly at times throughout next week if the GFS comes off.

Some 4c below average in places.

Edited October 29, 2014 by No Balls Like Snow Balls

[nick sussex]

Still some uncertainties upstream with the ne USA low. The depth and track does have a downstream effect on any cold air heading into the UK. Thereafter the interest is whether we'll see pressure holding onto the ne to force this low to cut se'wards as it approaches the UK.

 

You'll see that last nights ECM wanted to do this, this mornings less so. It's best to not take the post day 7 output too seriously at the moment as we've seen from the last few days some changes and its evident that whilst the models remain reluctant to stick the PV over Greenland that other avenues to cold might emerge after this possible cold snap.

[Mucka]

Clearly November is going to start cool and unsettled with a fairly typical zonal pattern setting up, for the first half at least but there is also a strong hint that troughing will occur through northern central Europe on occasion, at least enough to cause the Azores high to ridge into Scandinavia at times. This ridging may become more pronounced as we head toward mid month and I can see some form of block occurring to our East should the jet relent at all. Whether that is strong enough to affect our weather is hard to say but it may be enough to at least bring more settled conditions later in the month as pressure also rises from the South of the UK as low pressure systems are forced further north.

 

So unsettled and typical November weather for a couple of weeks then the possibility of settling down somewhat - perhaps? 

Edited October 29, 2014 by Mucka

[phil nw.]

Midlands Ice age I have removed your post and will pm you.☺

[Barry12]

Just seen this on Meteociel, the GFS in 3d

 

http://www.meteociel.fr/modeles/gfse_3d.php?mode=1

 

Has anyone used it?

Edited October 29, 2014 by Barry95

[shaky]

Pretty big upgrade regarding the northerly on the gfs 12z!!!more potent and heights are stronger and across the atlantic into greenland!!!maybe ecm was onto something yesterday!!!

[nick sussex]

Interesting GFS 12hrs run so far, the ne USA low is tracking further inland and better heights over Greenland.

[Cheshire Freeze]

Pretty big upgrade regarding the northerly on the gfs 12z!!!more potent and heights are stronger and across the atlantic into greenland!!!maybe ecm was onto something yesterday!!!

 

[nick sussex]

Both the GFS and GFS P go for a cold snap, the GFS looks better though in terms of the medium term as we might get troughing to set up to the west with pressure holding on to the ne.

[radiohead]

It's probably best to focus on the GFS parallel now, since it's running at significantly higher resolution and with a host of improvements over the older version. It will be replacing the old GFS on Dec 9th anyway. Older version is still useful as a type of "control" run too though.   

[Mucka]

First modelled lowland snow of the season for England - treat with a lorry load of salt.

 

 

UKMO also looks chilly though

 

 

Wrap up for bonfire night.

 

Edited October 29, 2014 by Mucka

[nick sussex]

It's probably best to focus on the GFS parallel now, since it's running at significantly higher resolution and with a host of improvements over the older version. It will be replacing the old GFS on Dec 9th anyway. Older version is still useful as a type of "control" run too though. 

That might be the case but the GFS P was very slow to develop the ne USA low which is crucial for events in Europe, indeed only yesterday it was on another planet compared to the rest.

 

Unless the ECM does something strange this evening then its wiped the board with all the other models, this gives further support to its better handling of these types of ne USA lows.

 

The UKMO looks a bit disappointing compared to the GFS, its more progressive and doesn't develop that low as much, we really want to see that develop as much as possible as that means a more ne track and a stronger ridge to its east.

Edited October 29, 2014 by nick sussex

[Cheshire Freeze]

First modelled lowland snow of the season for England - treat with a lorry load of salt.

 

 

UKMO also looks chilly though

 

 

Wrap up for bonfire night.

 

 

Aye looks like a disturbance running S across western areas on GFS and UKMO. Will keep my beady eyes on that one as you never know, the lamp post may be needed at some point :O

[SMU]

http://modeles.meteociel.fr/modeles/gfs/runs/2014102912/gfs-0-138.png?12

 

At last.....

 

Snow for the North & Possibly Ireland ( N)

[snowy weather]

http://modeles.meteociel.fr/modeles/gfs/runs/2014102912/gfs-0-138.png?12

 

At last.....

 

Snow for the North & Possibly Ireland ( N)

out of interest how can you tell from that where the snow is? (I am a novice) 

[No Balls Like Snow Balls]

Crikey the GFS has temps struggling to get above freezing in some places on Tuesday.

I will believe that when I see it though.

[Mark Bayley]

out of interest how can you tell from that where the snow is? (I am a novice) 

Snow would be restricted to Northern Scotland on that chart, although possibly high ground further south and in Northern Ireland (higher due points here). Colder air quickly filters south however, and dew points lower. A band of precipitation pushes south during the Tuesday, most likely giving snow to higher ground, possibly lower levels. All speculation though, and it will change

Edited October 29, 2014 by Mark Bayley

[snowy weather]

Snow would be restricted to Northern Scotland on that chart, although possibly high ground further south and in Northern Ireland (higher due points here). Colder air quickly filters south however, and dew points lower. A band of precipitation pushes south during the Tuesday, most likely giving snow to higher ground, possibly lower levels. All speculation though, and it will change

Tuesday.pngDewpoints.png

Thanks.  

[Barry12]

This is why you don't follow the ensembles, just yesterday some people were saying little change and November was going to be zonal and have above average temperatures. Looking at the models run now they are painting November to be average to below average temperature wise. There are zero signs aswell of the polar vortex getting strong, especially looking at tonights GFS run.

 

Day 10:

 

 

Polar vortex is weak and all over the place.

 

Day 16:

 

 

Polar vortex is still weak and all over the place.

 

 

 

Looks cold right throughout the run

 

 

 

All in all very good signs for November.

[IDO]

I would not get carried away with one GFS run bearing in mind their current below average performance. Lots of uncertainty at the moment and if you look at the GEM, that this morning had a Northerly, now is flatter and has average temps and rain:

 

D6:  And further on: 

Edited October 29, 2014 by i'm dreaming of...

[Barry12]

I would not get carried away with one GFS run bearing in mind their current below average performance. Lots of uncertainty at the moment and if you look at the GEM, that this morning had a Northerly, now is flatter and has average temps and rain:

 

D6: gem-0-156.png  And further on: gem-0-210.png

 

The ECM and UKMO are also showing a Northerly developing at day 6, the ECM 00z had average to below average temperatures throughout the run. I'm sure the GFS has been performing better than the GEM.