Model Output Discussion - 05/01/2016 18z onwards

[TEITS]

4 minutes ago, terrier said:

Don't know how u can say it's odds against when even the modes are flip flopping all over the place even this week. 

Lets be fair though the ECM/GFS/GEM in the medium range all show a horrific outlook and have done for several runs now. This is why we need to pray the UKMO is right.

[That ECM]

7 minutes ago, terrier said:

Don't know how u can say it's odds against when even the modes are flip flopping all over the place even this week. 

If you look at the 3 below and except that the gfs is slightly more progressive than the ECM which is slightly more progressive than the ukmo, are they really that different? It's difficult as Ukmo only goes to T144 but imo it would go a similar way to the other two. Time will tell but that is why I feel it's odds against. 

Please illustrate why you would feel differently. Not being funny, genuinely interested.

[JoeShmoe]

3 minutes ago, TEITS said:

Lets be fair though the ECM/GFS/GEM in the medium range all show a horrific outlook and have done for several runs now. This is why we need to pray the UKMO is right.

Correct, too many people take each set of runs in isolation instead of looking at series of runs and ensembles, most of which have been indicating the same overall trend for a period of time. The ukmo is out on a limb - I suspect personally as it may have a lower grid resolution in the Greenland area so be interesting to see if and when it backs down 

[Ali1977]

Please delete post above sorry, my error.

 

That ECM - the WAA is pretty similar on all 3 correct, the main difference which could lead to a prolonged cold spell is that the low to the South of Greenland isn't there on the UKMO, so the WAA/ Block wouldn't get bowled over as per ECM and GFS. In fact it could lead to the block growing on the UKMO.

[booferking]

12 minutes ago, TEITS said:

Lets be fair though the ECM/GFS/GEM in the medium range all show a horrific outlook and have done for several runs now. This is why we need to pray the UKMO is right.

 

8 minutes ago, That ECM said:

If you look at the 3 below and except that the gfs is slightly more progressive than the ECM which is slightly more progressive than the ukmo, are they really that different? It's difficult as Ukmo only goes to T144 but imo it would go a similar way to the other two. Time will tell but that is why I feel it's odds against. 

Please illustrate why you would feel differently. Not being funny, genuinely interested.

My eyes must be bad but downstream around USA eastern seaboard & Greenland tip there is  BIG DIFFERENCE in there lows.

Edited January 12, 2016 by booferking

[SMU]

^^^^^ 

its the  GFS falling towards the UKMO more amplified solution though not the other way round

look at the above charts then take the 00z 144 GFS from yesterday which is the same time as today's 120s above

you can see before the energy is progged over the block

now today it's going under

not mega swings in the height distribution but subtle swings in the shortwave pattern with big impacts on the UK

s

[That ECM]

52 minutes ago, Steve Murr said:

^^^^^ 

its the  GFS falling towards the UKMO more amplified solution though not the other way round

look at the above charts then take the 00z 144 GFS from yesterday which is the same time as today's 120s above

you can see before the energy is progged over the block

now today it's going under

not mega swings in the height distribution but subtle swings in the shortwave pattern with big impacts on the UK

s

Thanks for your explanation and trust me, I would like snow IMBY as high as small child but I was just giving my opinion. I watch with interest and hope you are right. It is through yours and others posts that I have learnt and feel I can give an opinion. 

Edited January 12, 2016 by Polar Maritime
To move discussion on..

[Kentish Snowman in Yorks]

Well already this morning we are seeing signs that the models (particularly the GFS) are disrupting the low pressure as it pushes in from the West to a much greater extent than was shown last night.

We are now reaching a tipping point regarding the pattern just beyond the weekend and having viewed the output from this morning, I am even more convinced the cold spell will be extended and may even intensify due to due to the energy heading SE into Europe and creating an Easterly with those frigid uppers in Europe being dragged in our direction.

This is all down to the models underestimating the strength of the block as mentioned yesterday.  I have a feeling we may see further cold upgrades on the 12z suite this afternoon...

[Severe Siberian icy blast]

44 minutes ago, That ECM said:

Thanks for your explanation and trust me, I would like snow IMBY as high as small child but I was just giving my opinion. I watch with interest and hope you are right.

its easy to see that all 3 of them have not just prolonged the cold but all 3 have a form of trough disruption . 

The gfs has been showing the Atlantic steaming in , only to backtrack , the ECM has been some what in the middle , but goes into ramp mode in fi . 

 

 

Edited January 12, 2016 by Polar Maritime
To move discussion on..

[Day 10]

My order of preference this morning would be UKMO, ECM, GFS. Let's hope the UKMO is right here, it seems to have been the most consistent recently with it wanting the high further north prolonging the cold. As Mucka stated earlier it's normally the UKMO is the usual party pooper when we want colder weather so let's hope this time around it's correct. The GFS keeps backtracking and moving toward the UKMO slowly each day as timescales move ever closer, and the ECM keeps being somewhere in between. Plenty of positives this morning.

Edited January 12, 2016 by Minus 10

[Dreamnine]

The week doesn't look particularly cold or snowy, (except on Northern hills) a few cool days then a swift return to South Westerlies.

[markwells]

looking through the gfs 00 ensemble members... apart from noting some massive variation..perturbations 6,11,12 and 18 catch my eye at t162 as showing various degrees of trough disruption. I wonder if that signal will be stronger on the 06? 

Edited January 12, 2016 by markwells
poor image

[syrinx]

28 minutes ago, Dreamnine said:

The week doesn't look particularly cold or snowy, (except on Northern hills) a few cool days then a swift return to South Westerlies.

I would tend to agree with this statement, unfortunately it looks like the frost or snow will be confined to 500m + - mainly the Peaks and other high areas.

You can see the Azores high pushing in here, and we all know they are super hard to remove once firmly in place.

I don't see any easy route to cold from here, it's looking really poor the more you go through the ensembles. Is the GFS wrong? Only time will tell, but it looks like a short lived little snap before a return of the Azores.

Edited January 12, 2016 by syrinx
no

[SMU]

So here it is  - shock proof the UKMO can pawn all the models at the most critical of times - & importantly when we needed it the most

An UKMO 144 chart that varifies very close & the GFS / ECM are miles away- 

note the scenario - Blocking to the NE & undercutting energy.

These are the 2 actual verification charts for 19th & 21st jan 2013 - it demonstrates the EXACT position we are in today- with the models at day 6

UKMO spot on at day 6, GFS miles away & ECM thinking of a different scenario -

Then continue to day 8 ( GFS & ECM ) to show how wrong they were

so - verified charts

sat 19 & mon 21st 13

2 classic undercutting charts - with sub zero maxima across england & a band of snow moving ESE - a great day that one.

So rewind to the 12z 's of the 13th 6 days before - at just T144 you would expext the models to be indicating this undercut & possible snow event - 

UKMO DAY 6 12z

as you can see thats a fair crack of the whip - all the energy going in the the right direction (SE) & snow on its way

now take the ECM 144 & 192

as you can see a little energy going under but at day 6 nothing - but it does get there at day 8 - with a more pronounced under cut-

Now onto out favourite rollercoaster model the GFS

Day 6 sees all but a tiny bit of energy moving SE at day 6 with no easterly - which then translates to a mild SW flow developing at day 8 ....

So going on from what ive said since 1st Jan is that once a blocking high to the North or NE is in place the UKMO seems to deliver better resolution to the locale of the high & subsequent jet disruption - even the ECM looks weak in its modelling-

This was backed up by Ian F yesterday in shorter fashion by saying the same thing.

 

so while we cant 'expect' it - at least we can safely say the UKMO could be the lead here not the GFS....

S

thanks Pm

Edited January 12, 2016 by Steve Murr
To move discussion on..

[Catacol]

4 minutes ago, Steve Murr said:

 

So going on from what ive said since 1st Jan is that once a blocking high to the North or NE is in place the UKMO seems to deliver better resolution to the locale of the high & subsequent jet disruption - even the ECM looks weak in its modelling-

Would agree with this. Over the years while ECM has the better global verification stats I have seen UKMO more often lead the way in the 3 - 5 day period for weather in our locale. Often this has been a frustration as it has diluted a potentially exciting spell... perhaps this time around it can be our friend. 2013 an excellent example Steve.

[BLAST FROM THE PAST]

9 hours ago, TEITS said:

I will finally give some advice to newer members on here.

You will at times read some very technical posts on here referring to various teleconnections and how these may dictate the weather patterns in the medium/long range. However it does not matter how promising these signals are as they mean nothing if this does not show up on the actual model output at a sensible timeframe. I mention this because if I had a pound for every post I have read promising one thing only for the model output to show the opposite I would be a very rich man.

I will add if I had a pound for every E,ly I have predicted I would be a millionaire.

In relation to our locality Dave I agree.  I think we have to see how the rest of Jan pans out as post 7 days isn't decided yet imo and it is not unknown that models haven't picked up on a signal as yet.  I do find it surprising though that if human assessment looking at the aam, glaam, naam [sorry that's a 1960s war], gwo etc etc suggests favourable poleward ridging/blocking why the models don't.   It still is only the 12th though, and if in ten days time we look like what the ECM looks like, then the game is done.  

I must admit I think I'm reading the script wrong unless things change post 7 days too

 

BFTP

Edited January 12, 2016 by BLAST FROM THE PAST

[northwestsnow]

UKMO continues to carry the torch for coldies this morning- 

GFS/ECM both go they way of the pear with some hideous outputs after the weekend.

I wont launch the towel until ukmo backs down.

[Hocus Pocus]

^^^^^^ Great post by SM explaining the strength and weaknesses of each individual model and what a great learning curve for many of us watching this week and next unfold.

Edited January 12, 2016 by Hocus Pocus

[johnholmes]

The post from Steve above illustrates, largely, what the anomaly charts suggested recently. That is the cold remaining out to about 19-21 January. Prior to that and unlike the synoptic models at times they showed the cold starting  around 11-12 for England (already there for  Scotland) and possibly lasting out to about 16th.

Beyond the 21st and I am afraid that both the ECMWF and GFS anomaly outputs show the block giving way with the cold weather being replaced by more Atlantic type weather. Currently, see below, NOAA at 6-10 shows nothing of this and even at 8-14 is not keen. If they both start to show a decrease in +ve heights and ridging which they have at the moment then we could be looking at the Atlantic returning. How long this might occur is impossible to say using the anomaly charts.

links

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

http://www.cpc.noaa.gov/products/predictions/814day/500mb.php

[irish1]

Well the ECM overnight has the Irish Met Office calling it for here anyway with the Atlantic bursting through beyond Sunday.

[SMU]

Cheers HP

infact looking at my post without opening any image & just looking down on the actual 19th V the UKMO chart in terms of the global anomalies both high & low heights - the UKMO was spectacularly good - I would go as far as to say thats one of the best modelled V verified charts ive ever seen -

If ian reads this its certainly a thumbs up for the UKMET model....

S

[northwestsnow]

1 minute ago, Steve Murr said:

Cheers HP

infact looking at my post without opening any image & just looking down on the actual 19th V the UKMO chart in terms of the global anomalies both high & low heights - the UKMO was spectacularly good - I would go as far as to say thats one of the best modelled V verified charts ive ever seen -

If ian reads this its certainly a thumbs up for the UKMET model....

S

Looking across the board its UKMO keeping the dream alive steve

I agree that gfs has moved in the right direction this morning but we really are reaching the tipping point now.

Oftern in the past UKMO has been isolated,esp when the others were showing massive cold - its broke my heart quite a few times.

FAX charts will be the key now as we are in the range, fingers crossed.

[JOPRO]

00hrs run seems to be a bit of an outlier from around the 19th, so lots of water to pass under the bridge as to where we are heading from next Monday/Tuesday, I really wouldn't be worrying about charts past 120/144Hrs. If we learn one thing from this episode it is that despite all the resent upgrades to the models they still struggle when we have cold synopsis for the UK, there just must be to many variables  with us being right next door to the Atlantic to factor in. This mornings trend is for the cold spell to me extended by a couple of days, lets see if that continues.

[TSNWK]

Morning Steve.

Is the event you described the one whereby we in North-west kent enjoyed a lovely Friday of Snow in sub-zero temputures - I think the temp' actually dropped from overnight values during the morning as a South-eastery was drawn over from a cold contienent, as the low pressure system advanced (showing clearly what a disrupting flow can do)

This was followed by a cracking Sunday Snowfall

Are you seeing something similar ?

Edited January 12, 2016 by TSNWK

[SMU]

15 minutes ago, TSNWK said:

Morning Steve.

Is the event you described the one whereby we in North-west kent enjoyed a lovely Friday of Snow in sub-zero temputures - I think the temp' actually dropped from overnight values during the morning as a South-eastery was drawn over from a cold contienent, as the low pressure system advanced (showing clearly what a disrupting flow can do)

This was followed by a cracking Sunday Snowfall

Are you seeing something similar ?

 

Yes mate it snowed all day sat although bexleyheath ( IMBY) the front fizzled a bit - where as to the SW on the downs they got 3-4 inches ( nearer 1.5/2 here )

This is a similar scenario here although perhaps not as condusive to snow - more prolonging the deep cold as its difficult to really see where the UKMO goes past 144 -

the atlantic shortwave is to accute to get into the UK but does stop the sinker - the high could respread Nw & NE so 168 is deffo still very cold but thereafter - unsure.... As no visibilty of shortwave pattern....

S