Model Output Discussion 01/09/17

[northwestsnow]

3 minutes ago, CreweCold said:

I'm very doubtful-

All very familiar to me, it has been the same way for the past few years. We see Euro heights repeat ad nauseam. The ECM has often over amplified things and I suspect we'll see a backtrack from it on the 0z run. 

Dont the stats state completely the opposite tho?

PS im not saying im not doubtful, 18z is dreadful compared the EC 12z, i would have felt much better if it had moved, infact, its worse than the gfs12 run before it.

Edited November 19, 2017 by northwestsnow

[Cheshire Freeze]

Just now, northwestsnow said:

Dont the stats state completely the opposite tho?

You have to understand that over the Hemisphere as a whole then it is on average the best model. However when it comes to modelling scenarios such as this, for our neck of the woods it is often a smidgen too amplified. Means very little in the grand scheme of things but to our 'on the ground' weather it has massive ramifications. We have seen it time and again.

[Allseasons-Si]

8 minutes ago, CreweCold said:

I'm very doubtful-

All very familiar to me, it has been the same way for the past few years. We see Euro heights repeat ad nauseam. The ECM has often over amplified things and I suspect we'll see a backtrack from it on the 0z run. 

Quiet rightly so,there is sooooo much model divergence in the short term,options are on a very big table with a large dumping of salt on it

we keep on saying this but...,we await the tomorrows runs

....and tomorrow is always day 10

Edited November 19, 2017 by Allseasons-si

[northwestsnow]

1 minute ago, CreweCold said:

You have to understand that over the Hemisphere as a whole then it is on average the best model. However when it comes to modelling scenarios such as this, for our neck of the woods it is often a smidgen too amplified. Means very little in the grand scheme of things but to our 'on the ground' weather it has massive ramifications. We have seen it time and again.

Not disagreeing with any of that Crewe- i was really hoping 18z would be better.

00z runs will determine whose right, the divergence really is at 96.:)

[Cheshire Freeze]

1 minute ago, northwestsnow said:

Not disagreeing with any of that Crewe- i was really hoping 18z would be better.

00z runs will determine whose right, the divergence really is at 96.:)

I'm not placing any stock in it but the latest CFS run features possibly the 'worst' temperature anomaly I've ever seen on that model for a winter month

Going forward I genuinely believe the writing is on the wall for December.

This doesn't exactly bode well either

[Ice Day]

Pretty awful 18z if cold is your thing, however given the differences between it and the 12z I think it's fair to say that the GFS has not got a handle on this at all. I've always wanted to say this....'more runs needed'!

[nick sussex]

For the GFS to be right both the ECM and UKMO have to be wrong at T96 hrs. The GFS deals with low pressure over the UK differently and doesn’t split the energy near the Azores till much later. 

This together with its flatter upstream pattern and it’s too quick to push the Quebec troughing east later. NOAA expect that to stall  into at least into Monday week.

 

 

Edited November 19, 2017 by nick sussex

[booferking]

Could well be halfway house ukmo

1 minute ago, CreweCold said:

I'm not placing any stock in it but the latest CFS run features possibly the 'worst' temperature anomaly I've ever seen on that model for a winter month

Going forward I genuinely believe the writing is on the wall for December.

This doesn't exactly bode well either

Is that a pause then a little uptake at the end i see on 30hpa

[bluearmy]

Eps clusters indicate aroufd 50% support for the northerly similar to the op - thereafter only 20% for euro low height anomoly with ridge across the top. On the plus side that's up from this morning! 

Chin up Crewe!

[Allseasons-Si]

Just to add,while the main chunk of pv is to be forecasted to move to the Siberian side then what is there to be worried about,better than it sit over the Greenland locale

just a thought.

[northwestsnow]

5 minutes ago, nick sussex said:

For the GFS to be right both the ECM and UKMO have to be wrong at T96 hrs. The GFS deals with low pressure over the UK differently and doesn’t split the energy near the Azores till much later. 

This together with its flatter upstream pattern and it’s too quick to push the Quebec troughing east later. NOAA expect that to stall at least into at least into Monday week.

 

 

yes i think crunch time will be the 0z runs - i take crewes point about EC over amplifying - we have indeed been here many times before.Maybe its me but it does seem the worse case scenario when it comes to UK cold always seems to be the blinkin right one.

GFS 18z and the Atlantic says no at pretty much every attempt at Retrogression - too much energy at every juncture!

Edited November 19, 2017 by northwestsnow

[bluearmy]

Worth making a note of the TD showing up in the west Pacific week 2 - that's the second run I've seen that feature and if it were to be able to be picked up into the general flow arcing out into the n Pacific then that really could be game on for December from a hemispheric perspective as we already see a propensity for amplification on the Pacific side in any case. 

[Derecho]

The big problem with the 18z is that pressure is stubbornly high over Italy (>1025mb) and that is the worst possible place for it. Contrast this with the ECM which has SLP in this region much lower and therefore the colder air can dig further south and east over the UK.

That is the problem, high pressure over this region means we really will struggle to get winter cold so I am really hoping the ECM is right. Given SLP has often been low over Italy this November and that is also backed to a considerable extent by the UKMO there is some hope.

Though high pressure over Europe has been dominant over the last 4 winters, think I've mentioned in previous years that it's partially due to the SST pattern over the North Atlantic and this November it has some similarities to the past 4. We will see what transpires but I'm very cautious.

Edited November 19, 2017 by Quicksilver1989

[coldwinter]

4 minutes ago, bluearmy said:

Worth making a note of the TD showing up in the west Pacific week 2 - that's the second run I've seen that feature and if it were to be able to be picked up into the general flow arcing out into the n Pacific then that really could be game on for December from a hemispheric perspective as we already see a propensity for amplification on the Pacific side in any case. 

But I thought winter was over as the incredible CFS is showing mild? 

[Allseasons-Si]

The 18z shows a warming in eastern Asia,wasn't there on the 12z,i know it's in la! la! land but good at predicting these trends out in FL  ,will keep an eye on this in future runs

night guys,will resume tomorrow.

Edited November 19, 2017 by Allseasons-si

[Cheshire Freeze]

Just now, coldwinter said:

But I thought winter was over as the incredible CFS is showing mild? 

Who has said that winter is over because the CFS is showing mild?

Of course it can be used as supporting evidence to compliment a plethora of further pointers such as the cycles within global climatic drivers and other background signals. The same is true of other long range modelling tools such as the GLOSEA.

Flippant remarks such as yours add nothing to the thread, and rather undermine those of us who actually want to get our head around such drivers, signals and NWP tools.

[Cheshire Freeze]

3 minutes ago, Allseasons-si said:

The 18z shows a warming in eastern Asia,wasn't there on the 12z,i know it's in la! la! land but good at predicting these trends out in FL  ,will keep an eye on this in future runs

night guys,will resume tomorrow.

Yes, strat forecasts are a lot less prone to the volatility that the trop forecasts suffer at that range. Worth monitoring!

[damianslaw]

Lots of model divergence at the moment - as there has been for days now, so no surprise, and as ever we shouldn't get caught up on any particular new run. When it comes to the GFS 18z more than any run it seems it always goes off on wild tangents so to speak, Wednesday gone it had deep rooted North easterly, now a balmy SW flow, tomorrow no doubt it will show a screaming northerly - goes with the territory. It is notorious for showing something every day..

 

[coldwinter]

8 minutes ago, CreweCold said:

Who has said that winter is over because the CFS is showing mild?

Of course it can be used as supporting evidence to compliment a plethora of further pointers such as the cycles within global climatic drivers and other background signals. The same is true of other long range modelling tools such as the GLOSEA.

Flippant remarks such as yours add nothing to the thread, and rather undermine those of us who actually want to get our head around such drivers, signals and NWP tools.

You don’t need to explain. I’m just not sure what adding ‘The writing is on the wall for December’ adds either. 

Edited November 19, 2017 by coldwinter

[Cheshire Freeze]

7 minutes ago, coldwinter said:

You don’t need to explain. I’m just not sure what adding ‘The writing is on the wall for December adds either’ 

It means the same as it did when I said it last year...with similar responses to yours about the same time in November as now...

It wasn't an off the cuff comment, nor out of the blue. I've been saying the same thing for weeks and have given my reasons many times as to why I believe we are heading where we may well end up heading over the next few weeks.

Even the more learned on here like Tamara have said exactly the same thing in fact. GP was possibly the first 'pro' to state the beginning of winter may be quite mild back in July/August when he was analysing the S Hemisphere winter and how it may affect our start to winter!

Edited November 19, 2017 by CreweCold

[damianslaw]

Going take 3 days off model watching again, as I have just done so, simply because the reliable timeframe remains very short - and there will be too much wasted energy comparing each run trying to find a trend, when short-term developments are likely to scupper any..

Hoping when I next look, we have a wintry weekend of sorts on the cards - I'm banking on a dryish theme at least for some winter light celebrations, no wet windy conditions please. 

[Daniel*]

CC I suggest you screw your brain back on you aren't stupid. May posting anything of CFS result in a lifetime ban be implemented?  

[Frosty.]

Delete please

Edited November 19, 2017 by Frosty.
Duplication

[karlos1983]

2 minutes ago, damianslaw said:

Going take 3 days off model watching again, as I have just done so, simply because the reliable timeframe remains very short - and there will be too much wasted energy comparing each run trying to find a trend, when short-term developments are likely to scupper any..

Hoping when I next look, we have a wintry weekend of sorts on the cards - I'm banking on a dryish theme at least for some winter light celebrations, no wet windy conditions please. 

Agreed, everywhere I’m looking at the moment shows complete uncertainty in the mid term. Quite how some are writing December off when we can’t reasonably say what next weekend will look like is beyond me.

Not sure I want to take 3 days off model watching as I’m pretty hooked to see how this will evolve, maybe I will just stick to the 12z each day. 

 

[Frosty.]

Just had a flick through the Gfs 18z and noticed it shows some cold spells for the north with sleet and snow at times, especially scotland..wouldn't take much change to see wintry weather further south too..I'm really looking forward to winter!