Model Output Discussion 1st Nov.2013

[Summer Sun]

Extended CFS shows some cold uppers starting to filter down into eastern Europe the UK stays settled and relatively mild for a time

 

 

The final week of Autumn sees slow changes to something cooler but remaining settled

 

 

One thing I have noticed since that bitter March is the lack of blocking for a lengthy period over Greenland even into December pressure remains quite low up there

 

[Purga]

Dreadful GFS 06z in the realistic term but at least FI still holds out some vague hope with pressure dropping over Europe

 

The AH could do with Foxtrot Oscaring back SE though.

[shedhead]

But look at the Atlantic, its in a blocked state in that chart. What could happen is that high could move in to bring a milder spell of weather or we get some kind of change from mainland Europe....

Or any other number or potential possibilities, therefore there really is no point in speculating over one individual chart 16 days hence, which is almost guaranteed to change again 6 hours from now... at that range it can only be about the bigger picture.

Edited November 7, 2013 by shedhead

[nick sussex]

For several days now the ECM has shown a little interest at days 9 and 10 in terms of a better NH profile for those looking for something colder however this hasn't moved any closer and I'd be very dubious until this changes. The GFS looks pretty horrid upto 240hrs with the PV Greenland love-in showing no signs of imminent divorce.

Looking at the ECM ensemble mean there is at least some support for a westwards displacement of the limpet high, but there remains the problem of energy spilling over the top so you might still get this displacement but end up with a more modified nw flow around the high.

Any wintry weather still looks a long way away, but its only November so not really worth getting too worried over if you're a fan of the cold and snow.

[shedhead]

For several days now the ECM has shown a little interest at days 9 and 10 in terms of a better NH profile for those looking for something colder however this hasn't moved any closer and I'd be very dubious until this changes. The GFS looks pretty horrid upto 240hrs with the PV Greenland love-in showing no signs of imminent divorce.Looking at the ECM ensemble mean there is at least some support for a westwards displacement of the limpet high, but there remains the problem of energy spilling over the top so you might still get this displacement but end up with a more modified nw flow around the high.Any wintry weather still looks a long way away, but its only November so not really worth getting too worried over if you're a fan of the cold and snow.

Precisely Nick, get disappointed about no wintry weather come the end of winter by all means, but not 3 weeks before it even starts! 

Edited November 7, 2013 by shedhead

[nick sussex]

Precisely Nick, get disappointed about no wintry weather come the end of winter by all means, but not 3 weeks before it even starts!

Yes to be honest I'm quite enjoying these pleasant conditions down here and it's better to get these charts now than in December. At the moment I just don't see a clear path to anything wintry, hopefully this changes past mid month but for the timebeing we're going to have to be a bit patient.

[bluearmy]

ECM london ens most definitely clustering chilly/cold around the 20th nov.

[shedhead]

Yes to be honest I'm quite enjoying these pleasant conditions down here and it's better to get these charts now than in December. At the moment I just don't see a clear path to anything wintry, hopefully this changes past mid month but for the timebeing we're going to have to be a bit patient.

Agree, it's been so mild recently the path is completely overgrown at the moment, but as I said several weeks ago I'd much prefer charts like this in Oct/Nov than Jan/Feb. The colder clusters for later in the month are encouraging, but nothing more than that at this juncture, in fact from a personal viewpoint I don't expect any decent cold weather until the 2nd half of winter.....as ever tho, time will tell.

Edited November 7, 2013 by shedhead

[Frosty.]

I think this is one of the biggest hints yet that we could be in for an Arctic Blast just after mid month, it could be short and sharp or more substantial but right now i'm pleased to see the Ecm 00z ensemble mean trending this way towards T+240 hours.

[Troubleatmill]

People in the south east will be praying this one comes off for a white xmas 

Edited November 7, 2013 by tempestas

[ronan]

This all seems very familiar to November 2010. Tentative signs of something colder on the way then come the 27th of the month we had our first snow which then lasted over a month! 

[Gaz1985]

This all seems very familiar to November 2010. Tentative signs of something colder on the way then come the 27th of the month we had our first snow which then lasted over a month! 

 

You sure? wasn't end of November 2010 a one in 50 year event? can't see anything "familiar" in the build up this November.

[Captain Shortwave]

People in the south east will be praying this one comes off for a white xmas 

Wish I was using the 00z CFS output for my slow building Christmas thoughts 

GFS offering nothing, at this point I feel there's no need to be thinking sledges or macs towards the end of the month, still too far away to really start believing. I hope for another promising ECM later.

[Gaz1985]

Finally signs of high pressure building less than a week, about time   

 

[Summer Sun]

Nothing much on offer for coldies this afternoon from GFS, any colder air only lasts a few days before getting replaced by milder Atlantic air

 

 

Low pressure continues to dominate over Greenland allowing high pressure to build over the UK

Edited November 7, 2013 by Summer Sun

[bluearmy]

I know the gefs are oft derided for their lack of ability to spot a pattern change but there really are very few members with a p/v worth its name by the 23 rd

[Cheshire Freeze]

I know the gefs are oft derided for their lack of ability to spot a pattern change but there really are very few members with a p/v worth its name by the 23 rd

 

Was just about to say exactly the same thing. Very strong signal for a -AO out in FI.

[bluearmy]

Was just about to say exactly the same thing. Very strong signal for a -AO out in FI.

 

i guess thats the easy part crewe - then we have to get the cold here !

[Cheshire Freeze]

i guess thats the easy part crewe - then we have to get the cold here !

 

Indeed. I have been thinking for a while that it would be a -AO winter but have stressed in the winter thread that getting the NAO negative isn't a sure thing, even with a -AO. Even so, I think we'll see the NAO go negative sooner rather than later....

[ITSY]

GEFS progressing colder, with the average upper temps dropping down to -2.5C for N England out in FI, with the operational a distinct outlier. More members below -5, almost all below 0 and those tentative snow signals popping up and about. Nothing major at this stage but the start of a pattern change (to colder/winter weather) could be emerging for late November. 

 

http://modeles.meteociel.fr/modeles/gens/graphe_ens3.php?x=266&ext=1&y=4&run=12&runpara=0

Edited November 7, 2013 by ITSY

[Captain Shortwave]

I know the gefs are oft derided for their lack of ability to spot a pattern change but there really are very few members with a p/v worth its name by the 23 rd

Well the models can pick up something that far away and carry it to verification in some form or another. I guess we will have to wait and see, but the GFS did do very well at picking out the warmer and more anticyclonic spells during the summer from beyond 10 days out.

Edited November 7, 2013 by Captain shortwave

[Cheshire Freeze]

Well the models can pick up something that far away and carrying to verification in some form or another. I guess we will have to wait and see, but the GFS did do very well at picking out the warmer and more anticyclonic spells during the summer from beyond 10 days out.

 

I tend to sit up and take more notice when the GFS/GEFS pick up on a more blocked pattern in FI because usually the GFS is very progressive with the Atlantic and has issues with sending too much energy too far N. I've seen quite a few instances over the last few years where the model has brought blocked solutions from far out in FI towards the reliable in a steady fashion.

 

Of course that may not be the case here but it sure has injected some interest.

[Barry12]

Not strictly on topic but the Met Office also see temperatures trending below average from Wednesday onwards:

 

UK Outlook for Tuesday 12 Nov 2013 to Thursday 21 Nov 2013:

Rain across southeastern England will clear on Tuesday morning with sunny spells and scattered showers following elsewhere, showers locally heavy and thundery across the north and west. It will be breezy with local gales across the north. By Wednesday, there should be more sunshine and fewer showers across the country with lighter winds. Temperatures will be near normal at first but it will turn colder by Wednesday. From Thursday to Saturday, southern areas should enjoy drier and brighter weather with lighter winds although with a fog and frost risk, whilst northern parts will be more unsettled with rain and stronger winds. By the end of the period, these unsettled conditions look set to return to the whole of the UK with the heaviest rain across the north and west.

Updated: 1138 on Thu 7 Nov 2013

 

 

They also remain on the fence for the end of November:

 

UK Outlook for Thursday 21 Nov 2013 to Thursday 5 Dec 2013:

The rather unsettled conditions will probably continue into the start of this period, but with the potential for the rain to alternate with longer drier periods, which could well include overnight frosts and fog patches. However, by the end of November confidence significantly decreases regarding which weather type is most likely to dominate. There are currently no strong signals indicating significantly above or below average temperatures or rainfall.

 

Hopefully this is reflected in the models and we trend below average during mid-month. It's certainly all still to play for!

Edited November 7, 2013 by Barry95

[TootyFruity]

Sorry but what would influence would an -AO have on our winter in the UK ... What is a -AO ?

[Skullzrulerz]

Sorry but what would influence would an -AO have on our winter in the UK ... What is a -AO ?

Less low's coming from the west i think