Model Output Discussion - The final stretch to Christmas

[winterof79]

Frosty , I absolutely love your positivity and hope !

I'm just finding IT difficult to follow on here because for every 4 comment favouring the cold there is then 1 or 2 comments taking it away!

Appreciate that nobody knows and there is still a massive chunk of winter to come.

I think the problem is when posters assess mean/averages 9 plus days away.Not knocking that by the way,just saying it is the study of themes that do not necessesarily varify.There is plenty to look forward to upto and including the weekend.

http://www.meteociel.com/ukmo/fax/fax84s.gif?2  the dotted line is the 528 Dam line splitting the UK and can mean snow especially on hills.

Thereafter an easterly with some strong winds for a time.

http://www.meteociel.com/ukmo/fax/fax120s.gif?2  not the latest fax but you get the "drift".

The probable outcome is then settled weather and hopefully the MLB will move n/e to Scandanavia

http://modeles.meteociel.fr/modeles/gfsp/runs/2014122400/gfs-0-192.png?0

[Anti-Mild]

Morning all! I have been a member of this forum for a long time, and I cannot recall a more complex and unpredictable period of model watching! Once the LP on Fri/Sat is past it must surely get a bit more "steady", but in which direction will it head? The models seem interested in building heights over Scandinavia, but there is also an argument to be made for a flatter, more zonal pattern. FWIW i think we will end up with a HP centred over the Shetlands with a slack E'ly flow, bringing cold and dry conditons over the country - seasonal but not snowy.

[Frosty.]

Frosty , I absolutely love your positivity and hope !

I'm just finding IT difficult to follow on here because for every 4 comment favouring the cold there is then 1 or 2 comments taking it away!

Appreciate that nobody knows and there is still a massive chunk of winter to come.

I go with the flow..and a cold flow is coming:-)

[nick sussex]

Morning all

 

Not much change in the overall outputs so no major dramas although the UKMO looks the least likely to develop a deeper cold easterly.

 

Its high orientation and low heights much further east in the Med, you really need low pressure over northern Italy to underpin the block and help to pull the deeper cold further west.

 

Apart from the UKMO the models all show varying degrees of easterly influence, the difficulty for the UK is often getting the block sufficiently north and orientated in such a manner that it can tap into the coldest air otherwise this heads sw into mainland Europe.

 

So at the moment this is the main uncertainty, deep cold or surface cold type inversion scenario?

 

In terms of the upstream pattern that is expected to remain reasonably amplified in response to the ridge into Alaska, this generally means that the lowest heights will remain further north, shortwave interaction with the PV will tend to shear some of this nw, it could help develop the easterly as this might help carve more dig of the jet to the west of the UK.

 

Overall a seasonal spell of weather coming up but the million dollar question, snow and deep cold still to be resolved.

 

My post might seem rather less than excited but easterlies and what they bring can vary, often the mere mention of an easterly in here draws up visions of Lake Effect Snow off the North Sea, I know people have been patient and put up with a long drawn out affair so far but I think we're just going to have to see how this develops.

 

So yet more patience needed! that's been the mantra for the last week!

Edited December 24, 2014 by nick sussex

[Lord Baltimore]

Morning everyone. Quite possibly the start of something special. My brother who works at the Met office has just rang me to wish me a Merry Xmas and said that the Easterly flow will strengthen during January with very low temperatures expected. He also said not much snow unless low pressure bumps into its Southern edge.

[karlos1983]

Thought I would have a look out of interest at the ECM Mean for the last 4 00z out puts for the 31st. If you take a look, what is clear in terms of "trend", is that where heights were shown as being to our south on the run from the 21st for the 31st December, with each run that has passed, the heights have transferred to the NE. Let's hope this trend continues.

 

Sorry if it seems an odd thing to do, but I thought it would highlight the current situation and where we may go more importantly, especially with what the GFS has been chucking out on it's venture to the pub last night!

21st D10

22nd D9

23rd D8

24th D7

[Chris K]

Morning everyone. Quite possibly the start of something special. My brother who works at the Met office has just rang me to wish me a Merry Xmas and said that the Easterly flow will strengthen during January with very low temperatures expected. He also said not much snow unless low pressure bumps into its Southern edge.

Bit sceptical of this. Its like these "my friend in the council told me gritters are on code red for snowmageddon" type posts.

I don't think any professional forecaster would say something will happen that far ahead.

Edited December 24, 2014 by Chris K

[John Snow]

Bit sceptical of this. Its like these "my friend in the council told me gritters are on code red for snowmageddon" type posts.

I don't think any professional forecaster would say something will happen that far ahead.

.....(edited)

Edited December 24, 2014 by John Snow

[cyclonic happiness]

Anyway....can we go towards the models and away from character assassination please?? It's Christmas after all :-) 

[Gibby]

Due to Christmas, venue and family commitments my report wil only be available via my website until after the New Year but it will be updated there at the regular times through the period. If I'm able I'll post a link here after issue but cannot guarantee that. However, may I take this opportunity to wish everyone on here a very Happy Christmas and New Year and thanks for your support through the year.

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm

[nick sussex]

Thought I would have a look out of interest at the ECM Mean for the last 4 00z out puts for the 31st. If you take a look, what is clear in terms of "trend", is that where heights were shown as being to our south on the run from the 21st for the 31st December, with each run that has passed, the heights have transferred to the NE. Let's hope this trend continues.

 

Sorry if it seems an odd thing to do, but I thought it would highlight the current situation and where we may go more importantly, especially with what the GFS has been chucking out on it's venture to the pub last night!

21st D10

22nd D9

23rd D8

24th D7

Thanks Karlos that's a great way of seeing how the ECM ensembles have developed that ridge into Alaska and sharpened up the troughing to the west of the UK, each step has developed that dig of cold air further south into the USA as the amplitude increased.

[John Snow]

Off topic but will the met office be working on Xmas day? or do no models and forecasts and warnings come out?

[Banbury]

Off topic but will the met office be working on Xmas day? or do no models and forecasts and warnings come out?

Skeleton staff I believe

[cheshire snow]

Hmmmmmmm really ?

 

1. Wouldn't he ring you tomorrow??

 

2. What is his job there?

could be fergie lol

C.S

[fergieweather]

Off topic but will the met office be working on Xmas day? or do no models and forecasts and warnings come out?

Every hour of every day.

[John Snow]

Thanks, will be worth logging in between drinks and food to check the models then

[fergieweather]

could be fergie lol

C.S

Er, no.

[inghams85]

Thanks for the kind words guys. I've been lurking for 15 years but im no expert, im certainly no meteorologist. What I have learnt is how the models work, there nuances, bias settings etc and have picked a good instinct up from being able to decipher a pattern going forward (maybe similar to TEITS, Steve Murr etc) Things still look on from this morning. What I will say is don't get too high or low from every model run from this point onwards because what will happen is the output will change the positioning of the scandinavian high and associated western european cold pool but what you would excpect to happen closer to time is for the scandinavian high to ridge further and further north and west which will only upgrade the easterlies going forward. The Stratospheric warming going forward could turn this from being a great cold spell to a VERY good cold spell with a bit of luck

[cheshire snow]

Er, no.

Only joking Ian, all the best to you, and thanks for everything

you contribute to the forum

C.S

[blizzard81]

Second ECM control run on the trot to show a very cold, fairly snowy easterly for debilt. Think this forum would have gone in to meltdown if the op had shown this scenario.

[Lord Baltimore]

In response to his job in Exeter, he is not a forecaster, but an analyst. Expect the medium range forecasts to change today.

[snowking]

Due to Christmas, venue and family commitments my report wil only be available via my website until after the New Year but it will be updated there at the regular times through the period. If I'm able I'll post a link here after issue but cannot guarantee that. However, may I take this opportunity to wish everyone on here a very Happy Christmas and New Year and thanks for your support through the year.

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm

 

I don't think I get enough opportunity to complement your continuously fair, unbiased and easy to understand overview of the models, and the time and effort you take every day to produce this is nothing short of phenomenal. A very merry christmas to you too and I am sure everyone is looking forward to your return in 2015.

 

Before we even consider potential Greenland warmings, instant trop responses etc. we perhaps needs to keep a closer eye on this weekend too. For the cold-hearted among you, here is the GEFS ensemble mean snowfall projection:

 

 

I suspect the GEFS is still a little too quick with this evolution vs the european suites, the ECMWF det certainly a little less bullish with totals when compared to what is shown above, but for anyone with travelling plans the combination of heavy rain, strong winds and potential for snow in places is really worth keeping a close eye on.

 

SK

[Banbury]

In response to his job in Exeter, he is not a forecaster, but an analyst. Expect the medium range forecasts to change today.

Ok, thanks for that

[bluearmy]

Seems to me that the trop/strat coupling over the next few days is quite sensitive and varying feed backs could lead to some weird and wonderful fi solutions. The old chestnut 'don't trust the models at Xmas' will be wheeled out with no strong evidence to support such a view. However, we will be missing some flight data tomorrow and there are areas upstream and to our nw which are important (eg the depression that sinks across us at the weekend is forming in a region with sparse recordings and maybe flight data could be significant) and may lead to some runs which are questionable (Xmas day 12z and Boxing Day 00z perhaps?).

[Troubleatmill]

Bit sceptical of this. Its like these "my friend in the council told me gritters are on code red for snowmageddon" type posts.

I don't think any professional forecaster would say something will happen that far ahead.

 

I work for the council lol, to be honest we only go off what met office says and what we can all see on the website with regard to warnings ect, they don't hide anything, its a public service