Model output discussion - 1st December onwards

[Geordiesnow]

2 hours ago, mountain shadow said:

Zero sign of any kind of Northerly blocking in any model output between now and month end,  this is standard strong El Nino stuff and well forecasted by almost all professional outlets. 

Wet and windy with temperatures dependent on where the Polar jet boundary is as depressions move through. Any snow confined to Northern hills and briefly to lower levels at times.

 

i'm not all that surprised this post has not got more likes because its not what people want to read but that is a good summery of the current output at the moment. 

The only hope I can see is if the Arctic high ridges southwards and some runs have shown this but then dissapears back towards the Arctic again and not affecting the weather patterns at all. 

The outlook despite what seems to be portrayed here is a very mild and at times very windy with brief interludes of some polar(but not really cold) air at times. 

Looking at the NH charts, it is really interesting too see just how "warm" it looks for December, USA is looking really mild and dry and no doubt snow cover will be below average here, parts of Asia/Russia is looking well above average at the moment and even though thePV is over the Arctic, its hardly the strongest PV(e.g very little in the way of purples or upper air temps below -25)  you will ever see.  Any real cold does look a long way at this moment in time but things can obviously quickly change. 

[Methuselah]

5 minutes ago, Geordiesnow said:

i'm not all that surprised this post has not got more likes because its not what people want to read but that is a good summery of the current output at the moment. 

The only hope I can see is if the Arctic high ridges southwards and some runs have shown this but then dissapears back towards the Arctic again and not affecting the weather patterns at all. 

The outlook despite what seems to be portrayed here is a very mild and at times very windy with brief interludes of some polar(but not really cold) air at times. 

Looking at the NH charts, it is really interesting too see just how "warm" it looks for December, USA is looking really mild and dry and no doubt snow cover will be below average here, parts of Asia/Russia is looking well above average at the moment and even though thePV is over the Arctic, its hardly the strongest PV(e.g very little in the way of purples or upper air temps below -25)  you will ever see.  Any real cold does look a long way at this moment in time but things can obviously quickly change. 

Just to test your theory: it's going to snow; light winds will auger well for countrywide even settling rates...

[Paul]

43 minutes ago, Ed Stone said:

Just to test your theory: it's going to snow; light winds will auger well for countrywide even settling rates...

Long way to go before we reach a point of light winds though. Latest GFS is up to the weekend and looking a tad stormy for some on both Friday and Saturday. Batten down those hatches!

 

[Mucka]

1 hour ago, johnholmes said:

The cold snap about two weeks ago was not supposed to happen because of the background signals. I'm not saying some big freeze will just appear but that it would be wrong to rule out some colder snaps.

 

Not sure where you get that idea from Nick, the anomaly charts showed this likely to happen at least 6 days prior to it occurring. They also, to my eyes, suggested countrywide cold for 3-5 days. So not a bad predict really. Perhaps you still disagree, I can post the relevant charts to illustrate my post if you wish?

 

I don't want to put words in Nick's mouth but he is likely referring to the 10 and 14 day anomaly charts.

If it is only 6 days out then we will have already been watching it unfold in the daily output and will already be looking for details anyway.

I would be interested to see what the 10 an 14 day anomaly charts were showing for the period Nov 21/23 see if they were picking it up at all and to compare with the actual anomalies. Here is the actual anomaly for Nov 21.

 

So anomaly charts for up to the 11th (10 day) and up to the 7th (14 day)

Edited December 3, 2015 by Mucka

[johnholmes]

25 minutes ago, Mucka said:

 

 

So anomaly charts for up to the 11th (10 day) and up to the 7th (14 day)

will this link do

 

mucka requ 3 dec 15.doc

no idea where a chart for March came from!

Edited December 3, 2015 by johnholmes
hope that is what you wanted, not sure if it has downloaded as I want with the new system

[johnholmes]

1 minute ago, johnholmes said:

will this link do

hope this is what you wanted Mucka, not sure it has downloaded as I wanted, not used to the new system yet!

 

mucka requ 3 dec 15.doc

 

Edited December 3, 2015 by johnholmes
add words

[Mucka]

5 minutes ago, johnholmes said:

will this link do

 

mucka requ 3 dec 15.doc

Thanks John and they clearly show a strong anomaly but weren't they initiated just 6 days out?

What I am trying to establish is how well they were predicting suc a strong anomaly further out. so for the 10 day initiated around the 11th and for the 14 day initiated around the 7th.

I did try  to check for myself but unfortunately can only find MO threads back to No 16th so it is great you keep records.

 

[Paul]

Just now, Mucka said:

Thanks John and they clearly show a strong anomaly but weren't they initiated just 6 days out?

What I am trying to establish is how well they were predicting suc a strong anomaly further out. so for the 10 day initiated around the 11th and for the 14 day initiated around the 7th.

I did try  to check for myself but unfortunately can only find MO threads back to No 16th so it is great you keep records.

 

All the old model threads are in the archive

https://forum.netweather.tv/forum/162-model-discussion-archive/

[johnholmes]

I saw the first indication some 6 days out but not before. I find it rare that their 8-15 pickes up anything before the 6-10 does and then very often it follows suite. There have been exceptions but not many in all the years I have been watching. Odd really.

In this instance the very first suggestion was, without trawling back through the charts, was either the Thursday or Friday before the event developed. If you like I can link you to the whole November data I saved, 19 pages long!

 

[Cloud 10]

http://www.cpc.ncep.noaa.gov/products/archives/short_range/srarc.ind.php

Link to NOAA/CPC archives for 6-10 and 8-14 day anomaly charts.

[Mucka]

34 minutes ago, johnholmes said:

 

LOL no thanks John

Paul and Cloud 10 have kindly provided direct links so I can check for myself.

Mods

Still getting issues with cached files and images in Chrome and even quoting posts brings up old posts or no text as above?

Have to clear cache manually which is a pain.

 

Edit

So here was NOAA for 19th to 25th initiated on the 11th which clearly failed to pick up a strong Atlantic ridge

 

 

And here is NOAA 10 day initiated on the 13th, again it clearly fails to predict  strong Atlantic ridge

 

 

The reason I bring it up is not because I don't think anomaly charts are useful at all but because when using the 10 and 14 day anomaly charts they need to be used along with all other charts otherwise because very often they will not pick up blocking trends at that range because they are simply an average anomaly of the ensembles which itself means some skill needs to be applied to pick out where the signal is being diluted and not only that but the ensembles are fairly weak at that range. (I'm not directing this at you John because I know you understand all that and I'm not directing it anyone else who uses anomaly charts but it is something that seems to get overlooked in here when they are not predicting any positive height anomalies at higher latitudes 10-14 days.)

Edited December 3, 2015 by Mucka

[northwestsnow]

GFS 12z looking more amplified as we leave high res.

Hopefully will allow the troughs to dig south east towards Europe in Fi

Edited December 3, 2015 by northwestsnow

[Paul]

6 minutes ago, Mucka said:

LOL no thanks John

Paul and Cloud 10 have kindly provided direct links so I can check for myself.

Mods

Still getting issues with cached files and images in Chrome and even quoting posts brings up old posts or no text as above?

Have to clear cache manually which is a pain.

Would be much better if you could report any issues in the thread here please:
https://forum.netweather.tv/topic/84553-forum-upgrade-please-read/

But in short, the posts/quotes in the editor looks like a bug, but you can just delete them and they stay gone without a cache clear. Image caching sounds like the site you're viewing them from, we don't get involved in that. But if I'm missing something there please post over in the other thread. 

[Ravelin]

Looking good in FI again on the latest GFS, but is any of this eye candy actually getting closer?

[northwestsnow]

Beautiful GFS with southerly tracking lows in FI and the euro high in the shredder!!

Edited December 3, 2015 by northwestsnow

[Liam J]

1 minute ago, Ravelin said:

Looking good in FI again on the latest GFS, but is any of this eye candy actually getting closer?

It's been throwing sporadic eye candy charts out in FI for 10 days+ now and they are no nearer to a reliable time frame. 

[tight isobar]

Most would take this at +48hrs...

Its at+300 

HOWEVER the trends are still there!

Lets seet what the 12z ecm has to offer

[Ali1977]

Decent FI again, and a slight upgrade in the METOs wording for later Dec...you never know. I wonder what the Gloesea model is predicting.

[Ravelin]

5 minutes ago, *Sub*Zero* said:

It's been throwing sporadic eye candy charts out in FI for 10 days+ now and they are no nearer to a reliable time frame. 

That's my current impression, glad it's not only me. ECM seemed to be briefly picking up on a change near the end of it's runs but I'm not sure that's consistent either.

 

5 minutes ago, tight isobar said:

Most would take this at +48hrs...

Its at+300 

HOWEVER the trends are still there!

 

The 'trend' from the GFS could be..."I ain't got a clue".

[Mucka]

Just now, Ali1977 said:

Decent FI again, and a slight upgrade in the METOs wording for later Dec...you never know. I wonder what the Gloesea model is predicting.

 

Yes I wonder if Fergie would care to comment on where the slight shift in emphasis has come from? How strong is any cold signal? Is it building?

[Summer Sun]

Hints from UKMO the jet stream moving north mid next week giving us a break from the wind and rain

[nick sussex]

2 hours ago, johnholmes said:

The cold snap about two weeks ago was not supposed to happen because of the background signals. I'm not saying some big freeze will just appear but that it would be wrong to rule out some colder snaps.

 

Not sure where you get that idea from Nick, the anomaly charts showed this likely to happen at least 6 days prior to it occurring. They also, to my eyes, suggested countrywide cold for 3-5 days. So not a bad predict really. Perhaps you still disagree, I can post the relevant charts to illustrate my post if you wish?

Well at 6 days or even upto 10 days you'd expect them to start hinting at something. The issue I have is that we can't rule out some colder snaps because the more medium longer range background signals are saying no, those same apparent medium longer range signals did not suggest that November cold snap. Which is exactly my point. I think  background signals are best viewed as either improving or lessening colder chances but should not be viewed as a fait accompli .

I should add re anomaly charts the problem can be sometimes because the CPC cover 6 to 10 and 8 to 14 days which can mute out any colder snaps if they're a few days long.

Edited December 3, 2015 by nick sussex

[Methuselah]

3 minutes ago, nick sussex said:

Well at 6 days or even upto 10 days you'd expect them to start hinting at something. The issue I have is that we can't rule out some colder snaps because the more medium longer range background signals are saying no, those same apparent medium longer range signals did not suggest that November cold snap. Which is exactly my point. I think  background signals are best viewed as either improving or lessening colder chances but should not be viewed as a fait accompli .

Which is precisely what they were doing. How else could I have correctly predicted snow (to my snaw-addicted granddaughter) 7 days' prior to its occurrence? It certainly wasn't through clairvoyance!

[phil nw.]

26 minutes ago, Mucka said:

 

Yes I wonder if Fergie would care to comment on where the slight shift in emphasis has come from? How strong is any cold signal? Is it building?

The word transitional mentioned in that MO outlook suggests mobile perhaps with more emphasis on pm air incursions getting further south.I am only speculating of course it could mean a mid-latitude uk high with surface cold -who knows?

In the meantime from what GFS/UKMO is showing is more of the same with some temporary ridging in the flow with exchange of airmasses as the jet meanders across us.

Nothing yet in the modeling to suggest any prolonged cold,just plenty of wind and rain with some hill snow further north.

No real eye candy even in FI as some say-this is eye candy

Now that is proper blocking-what we are seeing currently is simply minor amplifications in the jet which quickly pass by.

 

[bryan629]

This is what Fergie tweeted yesterday 

an Fergusson ‏@fergieweather  Dec 2

W COUNTRY CONT'D (5/5) Signals are more mixed later Dec. Hints of a waning of more vigorous weather; more changeable & *perhaps* colder too