Model Output Discussion - Colder spell ending, what's to follow?

[Mucka]

ECM 240

Unusual NH profile, still some promise and tease in that chart though plenty of wet and windy weather to get through first - don't mention the Z word, I did once but I think I got away with it.

Edited December 10, 2020 by Mucka

[KTtom]

Not a good set of runs this morning! Yes we still have an Arctic high on ECM but for the use it is to the UK it may as well be an Antarctic high!

Low after low in the run up to xmas, at least there are short periods of dryer weather in between as opposed to the constant rain we often get this time of year...ECM day 9...looks like a teenagers face on a very cold day!

 

Edited December 10, 2020 by KTtom

[Chesil View]

12 minutes ago, Dancerwithwings said:

Pert 5 would be bring us all a Very Merry Wintry Christmas  

 

It certainly would. 

[Dimie10]

I am what you would call an avid lurker on this site. I have been interested in weather (especially cold) all my life. I used to be on the old BBC weather site like a few of you on here i presume.

I just wondered why so many of you say not to trust forecasts past 5 days, yet talk about runs so far ahead that rarely come to fruition. What do you genuinely believe? will we have any cold weather in the next 10 days or should just keep away until after then to see if our chances improve?!!

[swfc]

26 minutes ago, Mucka said:

ECM 144 is more GFS than UKMO but with some differences.

 

All this talk of zonal is jinxing things 

ECM 192, Arctic high having little influence and Scandi ridge much weaker, heights over Greenland lower. Just the hint of a ridge in the Atlantic

 

The changes across the output seems to be pointing to a change of direction which may not be all bad.

Yes mucka the 10 day ec isn't has bad as it appears. Very little PV to the nw and good Heighths coming of the esb USA. All in Larry grayson land but looks none to bad and not throwing out outlandish out put 

[DavidS]

So what is the ECM serving us up this morning. Well for the next 5 days we’ll have some milder weather with rain, followed by a cooler 5 day period with you’ve guessed it folks, rain.

[swfc]

Just now, DavidS said:

So what is the ECM serving us up this morning. Well for the next 5 days we’ll have some milder weather with rain, followed by a cooler 5 day period with you’ve guessed it folks, rain.

What we're you expecting David? There's nothing in the current output to show anything else tbh

[swfc]

11 minutes ago, Dimie10 said:

I am what you would call an avid lurker on this site. I have been interested in weather (especially cold) all my life. I used to be on the old BBC weather site like a few of you on here i presume.

I just wondered why so many of you say not to trust forecasts past 5 days, yet talk about runs so far ahead that rarely come to fruition. What do you genuinely believe? will we have any cold weather in the next 10 days or should just keep away until after then to see if our chances improve?!!

Morning mate. Tbh make your own conclusions but if I was you stick to the ukmo for the semi reliable. If you want to look for so called trends then just look at the runs in general. Also nothing on the cards for cold in the next 10 days

Edited December 10, 2020 by swfc

[terrier]

Well I see the gfs & ecm bring everyone back down to earth this morning. The ukmo looks to be the best of the bunch but on it own. I’ve said it before and I will say it agin the ecm & gfs are looking very much like what the ec46 dayer is predicting which is lows off the  Atlantic and heavy rain. With milder air over the Xmas period. Let’s see what the update is today from the ec46 dayer. But I think they is a lot of hope casting for Xmas at the moment. It’s very much looking wet rather then white at the moment. And before anyone says the ec46 dayer is garbage it did call last winter spot on it was never interested in any cold last winter in its updates and turned out to be bang on the money. So I think I will go with milder air and rain for Xmas which is always a good bet for our little island and is our default weather. As we all know easterlys are as rare as hens teeth. 

[TSNWK]

18 minutes ago, Mucka said:

ECM 240

Unusual NH profile, still some promise and tease in that chart though plenty of wet and windy weather to get through first - don't mention the Z word, I did once but I think I got away with it.

So many pieces need to land for us.. I was bleating previously about lower heights in  Europe and that upstream was ok in general.. today I'm seeing on the above that we are getting the lower heights in Europe but upstream it's gone all flabby...

 

[dragan]

19 minutes ago, Dimie10 said:

I am what you would call an avid lurker on this site. I have been interested in weather (especially cold) all my life. I used to be on the old BBC weather site like a few of you on here i presume.

I just wondered why so many of you say not to trust forecasts past 5 days, yet talk about runs so far ahead that rarely come to fruition. What do you genuinely believe? will we have any cold weather in the next 10 days or should just keep away until after then to see if our chances improve?!!

there is almost zero chance of cold weather in the next 10 days, temps especially at night will be a bit above average. I say almost zero chance, unless every forecaster and model are wrong, then really there is no chance 

[Mr.B]

2 minutes ago, dragan said:

there is almost zero chance of cold weather in the next 10 days, temps especially at night will be a bit above average. I say almost zero chance, unless every forecaster and model are wrong, then really there is no chance 

Can you start backing up these assumptions with charts! #justsaying

[DavidS]

21 minutes ago, swfc said:

What we're you expecting David? There's nothing in the current output to show anything else tbh

All hope, no expectation

[SLEETY]

Nice ecm at the end, not much adjustment needed to put the whole of Europe in the Freezer

[Eagle Eye]

Arctic high is doing it's job, slowly it's a bit like my bus 1 hour to get from Woodchurch To Ashford Honestly. 

Low pressures being pushed down faster on Models like the Ecmwf

Personally something in between fast and slow is Called just right. 

This seems to think a 5oc Winter would be something to hope for with this model. 

[Eagle Eye]

13 minutes ago, SLEETY said:

Nice ecm at the end, not much adjustment needed to put the whole of Europe in the Freezer

Certainly looking good, the Ecm is moving us from the fridge to the freezer, we can be kept cold for longer once we enter the freezer. 

[Day 10]

1 hour ago, Dancerwithwings said:

Pert 5 would be bring us all a Very Merry Wintry Christmas  

 

Too dry for my locale!

[Bradowl]

50 minutes ago, Dimie10 said:

I am what you would call an avid lurker on this site. I have been interested in weather (especially cold) all my life. I used to be on the old BBC weather site like a few of you on here i presume.

I just wondered why so many of you say not to trust forecasts past 5 days, yet talk about runs so far ahead that rarely come to fruition. What do you genuinely believe? will we have any cold weather in the next 10 days or should just keep away until after then to see if our chances improve?!!

I'm same, hardly ever post on here, just regional section. 

A lot more knowledgeable posters on here than the BBC one of a few years ago. 

More than 5 days ahead can't be trusted that much but If models are showing same consistently run after run chances are good but they tend to show something different most of time, even inside 24 hours of runs. 

There's always great interest in if we're going to get a white Christmas, being a fortnight away it's still difficult to tell, we'll no more this time next week I should think. 

[Duane S.]

Arctic highs are strange beasts. So difficult to model in the first place and thus downstream forecasts often chop and change (even) more erratically than normal. They appear to meander, almost as if looking for a mid latitude link up.

They are an essential ingredient to that jackpot scenario but alas, more often than not, just tease before filling in later on like it was never there in the first place.

Will this time be any different? I fancy with the current atmospheric set up and background signals in general,  we have a greater than normal chance of it producing later down the line for us.  

Whatever happens though, intriguing watching how it all progresses.

[Eagle Eye]

1 hour ago, Dimie10 said:

I am what you would call an avid lurker on this site. I have been interested in weather (especially cold) all my life. I used to be on the old BBC weather site like a few of you on here i presume.

I just wondered why so many of you say not to trust forecasts past 5 days, yet talk about runs so far ahead that rarely come to fruition. What do you genuinely believe? will we have any cold weather in the next 10 days or should just keep away until after then to see if our chances improve?!!

Because the next 5 days have 50oc runs in Winter and - 10oc runs in Summer. 

[Eagle Eye]

7 hours ago, MATT said:

Excellent stuff guys and thanks for waking me up from my slumber GFS.. Absolute crackers on these ens tonight, and I feel they are growing in numbers. I think this place is missing a Boom... Its been ages since we had one.. Certain charts deserve it, and some of these ensembles most definitely do...

Well that's my Summer sorted out. 

[LRD]

GFS Ensemble spaghetti:

Less cold runs than previously I'm afraid. But the cold runs that are there are becoming colder

There's an awful lot of runs with average or slightly above average 850s though (reflecting the Met Office outlook I guess). The dip in the average 850s line has also been pushed back. Not great signs

The spaghetti is messy though and it might take some time to tidy up

Edited December 10, 2020 by LRD

[IDO]

The main models, not counting the ever-promising d6 UKMO that never gets anywhere, had been killing the Atlantic nascent ridging, and there was plenty of evidence that this would mean an incoming flatter pattern as the Arctic high drives the dynamics. Zero signs of the promised land of a Pacific ridge and the usual caveat with MJO signals, sometimes they are trumped by another variable (eg last year).

No comment on the d10 ecm chart for obvious reasons and the overall consensus from the gfs op backed up by the mean is the recurring pattern:

d8-16 gfs mean>> 

> A wedge near Greenland from failed Atlantic ridging, a meandering Arctic high not drawn anywhere due to the slack flow of the NH profile, and remaining the *potential* for cold to lower latitudes if and when we see more amplification in the system. A front-loaded winter they promised and for all intent and purpose the ingredients are there apart from the main one, and it will be a wasted December if we are stuck in this Groundhog day!

 

[Day 10]

UKMO the pick of the 3 again, the Arctic High having the greater influence forcing the pattern further south and the two lows in the Atlantic being kept apart.

As many have already said the Arctic High is very difficult to model so is obviously causing even more headaches for these super computers!

Feet on the ground but enjoy the ride, extremely interesting model viewing at present.

Will Santa deliver a bucket of snow or a bucket of water??

[jules216]

Northern blocking slowly vanishing on the EPS extended clusters replaced by a version of Sceuro High pressure. It looks like it might get cooler in the south western Euro Asia to the east of Europe for a change