Model output discussion - 1st December onwards

[booferking]

3 minutes ago, feb1991blizzard said:

ECM PPN charts here booferking.

 

http://en.vedur.is/weather/forecasts/atlantic/

Thanks for that..

Edited December 27, 2015 by booferking

[damianslaw]

Didn't Glacier Point say 27th Dec would be the day for change - could he be spot on...

UKMO normally the most reserved model is showing trough disruption as early as 96 hours - we are not talking 10 days plus... ECM takes longer but eventually gets there, though just outside the reliable timeframe, we are not talking fantasy land. GFS powers up the atlantic, but the eventful evolution would be for low pressure to come unstuck over the country stall and energy dissipate SE allowing heights to build out of NW Russia towards Norway.

Its been the most promising day for cold snow lovers of the winter so far (not saying much). I would be surprised now if the models backtrack too much from the evolution to colder conditions - a pincher movement from the east and west - we have cold uppers attacking us from both sides, the jet heading southwards.

We don't need significantly cold uppers either to achieve low level snow, slider lows stalling and a slight continental flow ahead can cool the air markedly, producing favourable dewpoints and where precipitation is heavy evaporative cooling can take hold.

The 12th produced snow here, despite uppers around 0 degree mark!

I wonder if the countryfile forecast might hint at a colder start to New Year at least - the BBC yesterday were saying some models are suggesting a colder start to the new year, but they firmly went with mild for the foreseeable- mmm I wonder if they will be eating their words- given what the UKMO is showing tonight it would be very strange if the long range forecast doesn't at least talk about colder weather to start the new year - at least relative to now.

[nick sussex]

Just now, Froze were the Days said:

100% agree Nick - I personally feel there will be too much energy from that scenario and not the stall of the LP that this run shows.

If I'm being honest the ECM flirts with disaster too many times this evening, its like the James Bond of outputs this evening where by it dodges several bullets which miraculously don't hit and then runs off into the sunset with the stunning brunette!

My first rule of cold synoptics, what can go wrong and how much margin for error. The ECM has a lot that can go wrong and low margin for error.

Of course in the UK cold synoptics are often finely balanced but I don't like this crossing Niagara on a trip wire that the ECM has delivered. I've now amended my score which has dropped to 6/10 which factors in likely stress to coldies!

[Mucka]

Not certain if it hasn't been posted already but the GFS parallel 06z was interesting with decent undercut of the first and second of our potential trigger lows.

 

 

Giving us this day 10 chart

And then this channel low.

 

So cold and snow are certainly still a good possibility according to the model output we see,

Edited December 27, 2015 by Mucka

[SMU]

Damienslaw - GP kept reffering to a persistent northwesterly flow - nothing about a continental flow ....

Anyway my comments on tonight -

overall things remain very positive - the 3 steps to cold from the east in the UK are 

* eastern europe 

* Central europe

* Western europe ( obviously lol ) with step 3 the hardest to forecast & the most volatile

I would score the ECM 8/10 tonight -

why?

well its not the classic big draw Easterly we hoped for - a la 91 however all that means is the convective snow threat may be off the menu -

However , to get widespread snow in the UK it requires an element of the atlantic being present with the polar front straddling the UK

The most important element today was for the models NOT to shunt the upper air cold pool NW out of europe into scandi as once its up there its hard to recover any cold -

What the ECM has done is build the ridge over the top towards iceland holding that deep cold over central / western europe- its then on tap to filter into slider systems that are alligned NW SE across the UK

The ECM 192/216/240 has very high snow potential for the UK from frontal snow events & crucially at 240 its looking like theres plenty of sustainability post that timeframe

so often do we see cold hitting the UK at 168 only to already be seeing the end at 240

very exciting charts at the moment however FI still at 120-144 leaves stage 3 open to a lot of volatilty

we could still hit the jackpot chart at 192 but also still miss the deep cold altogether....

exciting times in a period of blocking not forecast by anyone as theblock has developed well before NYD....

S

[bradymk]

7 minutes ago, nick sussex said:

If I'm being honest the ECM flirts with disaster too many times this evening, its like the James Bond of outputs this evening where by it dodges several bullets which miraculously don't hit and then runs off into the sunset with the stunning brunette!

My first rule of cold synoptics, what can go wrong and how much margin for error. The ECM has a lot that can go wrong and low margin for error.

Of course in the UK cold synoptics are often finely balanced but I don't like this crossing Niagara on a trip wire that the ECM has delivered. I've now amended my score which has dropped to 6/10 which factors in likely stress to coldies!

Haha. Very true. It may certainly be a stressful upcoming week for us coldies but even though the ECM is not perfect, I am very happy considering only 3 days ago we were seeing this output for next Sunday.

To this for next Sunday from tonight's run.

Momentum has possibly swung in our favour and is building...

[Frosty.]

There could be a lot of edge of the seat or behind the sofa model watching during the week ahead, the Ecm 12z this evening shows tons of wintry potential later in the run which would increase much more beyond T+240 hours...this today is by far the most exciting model watching so far this season and hopefully winter will get the massive kick start it desperately needs through the first half of January...

[SLEETY]

22 minutes ago, Mucka said:

Ye wuths it is, great to see some cold options open up and developed in operational output though.

It is going to be fascinating to see what eventually develops and as others have said, at the very least it looks likely the PV will come under increasing pressure with opportunity for improved amplification prospects through January.

Now when will the MetO get on board.

 

If ,when it cimes In to The reliable time-frame whIuch With an easterly can be as little as 72 hours away

[MR EXTREMES]

I have seen this go wrong so many times over the years but I think El Niño weakened  might be working in our favour.

solar activity has fallen to the jet going south is a good sign if cold is what you want

Edited December 27, 2015 by emotional rollercoaster

[SLEETY]

It can take several attempts with an easterly before it hits these shores,so still all to play,for

[The Enforcer]

21 minutes ago, bradythemole said:

Haha. Very true. It may certainly be a stressful upcoming week for us coldies but even though the ECM is not perfect, I am very happy considering only 3 days ago we were seeing this output for next Sunday.

To this for next Sunday from tonight's run.

Momentum has possibly swung in our favour and is building...

What might the current ECM T+240 look like by the time it reaches T+168?

Edited December 27, 2015 by The Enforcer

[Skullzrulerz]

I think i be staying on the fence for a while until it's near upon us..Even then it can all go wrong and why becuase we seen all go wrong even 48 and even 24 hours..

However it does how good/great support for a return to normal/colder weather in early January however i would be careful because it seems complex and it could go wrong at any time it could also strike gold too..

All to play for by the looks of it.  i seems the xmas has changed things for the cold fans so i just needs to stay on track..

[Country Boy]

  HAPPY NEW YEAR ALL.

Looks like  Net Weather winter forecast is going to be spot on...it does say middle two weeks of January  will be wintery.

[Costa Del Fal]

I don't mean to be off topic here but rather make a brief albeit important point.

Whilst the start of January is subject to much more change, not long ago it was said the models are so predictable now and that much fun has been taken out of model watching compared to a few years ago.

Well just a few days ago who would have thought we would be looking at a shot of cold weather (not saying guranteed at all) and snow? To some, the whole long wave pattern was secured until mid Jan it seemed. How quick things can change and a vital point to always remember. Anything is always possible pretty much. It's always important to make an holistic assessment of the situation and forecast, by which I mean always take consideration of both the tropospheric and stratospheric forecasts, in particular good to see and remember how the stratosphere is playing out longer term. I certainly recommend all members take a chance to learn about the stratosphere of they can.

In summary, it seems like we have found the fun (and stress!!!) in model watching again!

Edited December 27, 2015 by Costa Del Fal

[cyclonic happiness]

11 minutes ago, Costa Del Fal said:

I don't mean to be off topic here but rather make a brief albeit important point.

Whilst the start of January is subject to much more change, not long ago it was said the models are so predictable now and that much fun has been taken out of model watching compared to a few years ago.

Well just a few days ago who would have thought we would be looking at a shot of cold weather (not saying guranteed at all) and snow? To some, the whole long wave pattern was secured until mid Jan it seemed. How quick things can change and a vital point to always remember. Anything is always possible pretty much. It's always important to make an holistic assessment of the situation and forecast, by which I mean always take consideration of both the tropospheric and stratospheric forecasts, in particular good to see and remember how the stratosphere is playing out longer term. I certainly recommend all members take a chance to learn about the stratosphere of they can.

In summary, it seems like we have found the fun (and stress!!!) in model watching again!

Oh yeah, that was me. I was upset because nothing was even showing that was remotely  interesting in FI or anywhere.   Well....................... now I have my interest back :-D

[Cheshire Freeze]

8 minutes ago, Costa Del Fal said:

I don't mean to be off topic here but rather make a brief albeit important point.

Whilst the start of January is subject to much more change, not long ago it was said the models are so predictable now and that much fun has been taken out of model watching compared to a few years ago.

Well just a few days ago who would have thought we would be looking at a shot of cold weather (not saying guranteed at all) and snow? To some, the whole long wave pattern was secured until mid Jan it seemed. How quick things can change and a vital point to always remember. Anything is always possible pretty much. It's always important to make an holistic assessment of the situation and forecast, by which I mean always take consideration of both the tropospheric and stratospheric forecasts, in particular good to see and remember how the stratosphere is playing out longer term. I certainly recommend all members take a chance to learn about the stratosphere of they can.

In summary, it seems like we have found the fun (and stress!!!) in model watching again!

It was obvious the NH pattern was changing into the new year well before Christmas (even if it wasn't to impact the uk directly)... I said as much MANY times. Though we had the usual drama queens proclaiming January would be just as mild/+AO as December.

[nick sussex]

22 minutes ago, Costa Del Fal said:

I don't mean to be off topic here but rather make a brief albeit important point.

Whilst the start of January is subject to much more change, not long ago it was said the models are so predictable now and that much fun has been taken out of model watching compared to a few years ago.

Well just a few days ago who would have thought we would be looking at a shot of cold weather (not saying guranteed at all) and snow? To some, the whole long wave pattern was secured until mid Jan it seemed. How quick things can change and a vital point to always remember. Anything is always possible pretty much. It's always important to make an holistic assessment of the situation and forecast, by which I mean always take consideration of both the tropospheric and stratospheric forecasts, in particular good to see and remember how the stratosphere is playing out longer term. I certainly recommend all members take a chance to learn about the stratosphere of they can.

I think the issue is that there might be too much emphasis on the strat playing ball to deliver wintry weather to the UK.  So that this becomes the centre of attention and other variables like the MJO take second place. I'm not diminishing the role the strat plays as it is a big player however you only had to look at some of the twitter comments from certain forecasters to realize that this has become like Moses parting the Red Seas, no Moses no cold! I'm not saying that cold is definitely on the way but talk of a Russian block last week would have been met with derision in some quarters, so although an angry looking PV does make things more difficult its not impossible, it can be angry but  if it moves and orientates more favourably this can deliver a window of opportunity.

Edited December 27, 2015 by nick sussex

[summerplume18]

When do the ECM ensembles come out?

[Costa Del Fal]

5 minutes ago, nick sussex said:

I think the issue is that there might be too much emphasis on the strat playing ball to deliver wintry weather to the UK.  So that this becomes the centre of attention and other variables like the MJO take second place. I'm not diminishing the role the strat plays as it is a big player however you only had to look at some of the twitter comments from certain forecasters to realize that this has become like Moses parting the Red Seas, no Moses no cold! I'm not saying that cold is definitely on the way but talk of a Russian block last week would have been met with derision in some quarters, so although an angry looking PV does make things more difficult its not impossible, it can be angry but  if it moves and orientates more favourably this can deliver a window of opportunity.

Absolutely Nick. I certainly don't want to proclaim the strat as our God either. However it cannot be denied its increasing importance. Always good to know about it to apply judgement when assessing the troposphere too.

[SnappyClap]

http://www.bbc.co.uk/weather/features/35186788

Just looked at the end of the bbc forecast , they still want to stick with the mild theme for january but they said it probably could be mild !!!!. however they said 1 or 2 of there models are indicating colder weather !!

[bluearmy]

10 minutes ago, summerplume18 said:

When do the ECM ensembles come out?

Slow on meteociel but seen them on weatherbell

the control is quite similar to the op but post day 10, the Atlantic swings through (which is mirrored in the ens mean/anomolys).  the trough then sinks se through the UK to become a euro trough and the deep cold uppers remain to our ne ready to be brought across the North Sea. On the means, (referring back to Steve's post earlier) , the deepest cold is moved nw into Scandi Pre day 10. 

the spreads are going to be important for me this evening and no doubt Ian will avail us with any relevant info on the clusters. 

Edited December 27, 2015 by bluearmy

[swilliam]

4 minutes ago, summerplume18 said:

When do the ECM ensembles come out?

Short ensembles out - not much support for the OP again

[nick sussex]

Just now, Costa Del Fal said:

Absolutely Nick. I certainly don't want to proclaim the strat as our God either. However it cannot be denied its increasing importance. Always good to know about it to apply judgement when assessing the troposphere too.

Yes of course. If the strat was more favourable a colder easterly would have likely been a slam dunk as it is its still a long haul . I think however at this time its going to be a more frontal snow scenario if things fall into place and I still have issues with the ECM's rocky path in trying to deliver that.

[Grimsby Snow Lover]

1 minute ago, swilliam said:

Short ensembles out - not much support for the OP again

 There is some support though which is a relief, at least these balmy temperatures should disappear soon. 

[bradymk]

ENS not quite backing the op yet but the control does go cold also. Still a large cluster of milder members but of course it doesn't mean these are right either. Support grows but the jury is still out.