Model output discussion - 5th December 2016 - Into Winter we go

[Gavin Hannah]

Wow, just clicked though the 00z run 1040mb High pressure .. are you kidding me.

[Seasonality]

2 minutes ago, Gavin Hannah said:

Wow, just clicked though the 00z run 1040mb High pressure .. are you kidding me.

You mean this one? Not out of the realms of possibility Gavin, as I said in earlier post this isn't the first output to show such an outcome.

 

[Frosty.]

Tomorrow somewhere in the uk should reach 15/16c 60f..BBQ and shorts weather between early / mid Dec..not bad huh!

[bobbydog]

2 minutes ago, Gavin Hannah said:

Wow, just clicked though the 00z run 1040mb High pressure .. are you kidding me.

Yep.

And i'lI raise you a 1065mb on the parallel.....!

[Blessed Weather]

Matt Hugo tweet this morning:

"HRES GSM model same as 00Z EC with an important trough disruption down to Iberia by 240hrs = marked build of pressure over the UK".

[northwestsnow]

Much improved output this morning imho, that 96-144 absolutely critical.Need the azores high to get north of the UK...

[Seasonality]

3 minutes ago, northwestsnow said:

Much improved output this morning imho, that 96-144 absolutely critical.Need the azores high to get north of the UK...

Morning @northwestsnow I made a gif so everyone could see the critical timeframe. I think you've hit the nail on the head.

 

Edited December 6, 2016 by Seasonality

[snowy weather]

12 minutes ago, Frosty. said:

Tomorrow somewhere in the uk should reach 15/16c 60f..BBQ and shorts weather between early / mid Dec..not bad huh!

Good stuff. Hoping for another mild December like last year. Makes commuting and working easier.

[Summer Sun]

ECM

5th to 11th

Temperatures above average - rain below average

12th to 18th

Temperatures remaining above average - rain below average in the far south above average in the north-west and a weaker signal elsewhere

19th to 25th

Weaker signals for the temperature may be below average for the ROI, NI and Wales but elsewhere no strong signal - rain above average in the west weaker signals for the east

26th to 1st

No strong signals for the temperature - rain below average for the south above average for the far north of England, Scotland, ROI and NI

[Frosty.]

15 minutes ago, snowy weather said:

Makes commuting and working easier.

Can't argue with that part

First mild spell of winter 2016/17 is almost upon us, it's already reached knockers woodshed.

Edited December 6, 2016 by Frosty.

[swilliam]

1 hour ago, Steve Murr said:

Note the proper anomaly-

That is the anomaly of 1 run and therefore will obviously be much larger. The previous post that you commented on showed  a mean anomaly in this position which, being an average of 21 runs, was much smaller of course. You dismissed this as just showing slightly less low pressure which for the mean was of course true. In practice though it was showing some runs (6/7) with HLB set against many runs that were climatically normal.

Looking at the mean anomaly at this time shows something similar if a little stronger  due to the increased number of runs now showing HLB.

In my view relatively small mean anomalies in the mean can be of significance but do not necessarily mean one of the smaller number of runs is going to come to fruition. Same with other long range products such as EC46. A small +ve deviation from the climate mean can be significant but does not necessarily mean HLB is going to set up shop in this precise region. This is the EC46 3rd week which was put up yesterday evening - shows something very similar apart from also having some lower heights to the SE. Also much as IF alluded to with everything aligned NW-SE

Note: if we do see a black hole on the mean charts then we are in business

Edited December 6, 2016 by swilliam

[bluearmy]

You don't need a black hole anomoly. 

The eps in agreement with the 46 at day 15. 

[AWD]

15 minutes ago, Summer Sun said:

ECM

5th to 11th

Temperatures above average - rain below average

12th to 18th

Temperatures remaining above average - rain below average in the far south above average in the north-west and a weaker signal elsewhere

19th to 25th

Weaker signals for the temperature may be below average for the ROI, NI and Wales but elsewhere no strong signal - rain above average in the west weaker signals for the east

26th to 1st

No strong signals for the temperature - rain below average for the south above average for the far north of England, Scotland, ROI and NI

15 minutes ago, Summer Sun said:

ECM

5th to 11th

Temperatures above average - rain below average

12th to 18th

Temperatures remaining above average - rain below average in the far south above average in the north-west and a weaker signal elsewhere

19th to 25th

Weaker signals for the temperature may be below average for the ROI, NI and Wales but elsewhere no strong signal - rain above average in the west weaker signals for the east

 

Apologies for quoting twice.  The quoting system still isn't working properly on my phone.

I wonder what's causing the noticeably higher temp anomalies over the GIN area on W3 & W4 of those charts, especially when compared to W1 & W2?

[SMU]

28 minutes ago, swilliam said:

Note: if we do see a black hole on the mean charts then we are in business

[Paul_1978]

19 minutes ago, swilliam said:

Note: if we do see a black hole on the mean charts then we are in business

Not at T+384 it won't.

[SMU]

13 minutes ago, Steve Murr said:

32 minutes ago, swilliam said:

Note: if we do see a black hole on the mean charts then we are in business

The anomaly I quoted on the day ( check back ) was in a different non favourable place & there was no euro low heights -

Also that mean would now be around T276 - which is still there at that time but still not in the right place -

- move onto the t384 mean & its better positioned with slightly lower euro heights-

however at 384 its a little to far out to get excited about-

 

 

Edited December 6, 2016 by Steve Murr

[knocker]

No significant changes in the ten day time frame. By the end of the EPS a trough to the NW and over Iberia/NW Africa. Positive anomalies to the NE but only slight ridging over Scandinavia. Ergo an upper flow from the westerly quadrant and temps around average.

Edited December 6, 2016 by knocker

[johnholmes]

Little sign on the anomaly charts of anything other than a 500mb flow from south of west out to day 14. Obviously the odd day could see surface cold but no deep cold likely. The NAEFS chart at 240h a bit more promising for cold and it does show a tendency for the height anomaly at 500mb to drift a bit further north, see below. So out to 19 December at least little if any sign of deep cold developing.

http://www.meteociel.fr/modeles/naefs_cartes.php?mode=0&code=0&ech=192&map=1&runpara=

http://www.cpc.noaa.gov/products/predictions/610day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

If these charts are anywhere near accurate in the time scales shown then pretty much all the LRF outputs look to be on dodgy ground. Professional and amateur, at least up to Christmas. Much head scratching as to what caused this. The tropical storm over Sri Lanka and SE India has been mentioned but I rather doubt that. One storm seems unlikely to have such a long term effect to me. I could be wrong so please drop your views in here please.

[jvenge]

12 minutes ago, johnholmes said:

If these charts are anywhere near accurate in the time scales shown then pretty much all the LRF outputs look to be on dodgy ground. Professional and amateur, at least up to Christmas. Much head scratching as to what caused this. The tropical storm over Sri Lanka and SE India has been mentioned but I rather doubt that. One storm seems unlikely to have such a long term effect to me. I could be wrong so please drop your views in here please.

Hi,

I guess it depends. Don't they base it on the most likely from a cluster of options? So, a better question may be was there a cluster showing the referenced outcome and did it become more pronounced after that tropical storm? 

If it was there but was in a minority cluster and that cluster became bigger after that tropical storm, I'm not sure if there is much head scratching to be had, as it was then always known to be a possible outcome.

[Grimers]

According to the GFS and ECMWF, a fairly mild outlook with a brief interlude of cooler conditions on Sunday before a return to mild conditions seems likely.

       
        

Unfortunately, it seems that a mild more than a cold Christmas period is likely and as others have stated in the previous thread, milder conditions are likely to win due to our position and being surrounded by warm seas. However, as you can see from the last chart on both the GFS and ECMWF, I still think there's a chance of colder conditions being present for Christmas.

Edited December 6, 2016 by Grimers

[Summer Sun]

Mean pressure remains high into Christmas week - only a handful of the ensembles take pressure sub 1020mb

The period from tomorrow to Sunday looks the mildest with temperatures more spring-like than anything else

[Ali1977]

7 minutes ago, Summer Sun said:

Mean pressure remains high into Christmas week - only a handful of the ensembles take pressure sub 1020mb

The period from tomorrow to Sunday looks the mildest with temperatures more spring-like than anything else

Temps look pretty cold on that chart from the 18th, and I would think it will at least be frosty in any clear sky.  A slight realignment of the high could start bringing something a fair bit colder still, not sure any snow just yet as the uppers around the high don't look conducive..  

Over to the 06Z to see if it strengthens the idea!!

[Grimers]

2 minutes ago, Ali1977 said:

Temps look pretty cold on that chart from the 18th, and I would think it will at least be frosty in any clear sky.  A slight realignment of the high could start bringing something a fair bit colder still, not sure any snow just yet as the uppers around the high don't look conducive..  

Over to the 06Z to see if it strengthens the idea!!

Well, I'd think if that chart is showing uppers then it'd be too warm for snow anyway.

Edited December 6, 2016 by Grimers

[Seasonality]

3 minutes ago, Ali1977 said:

Temps look pretty cold on that chart from the 18th, and I would think it will at least be frosty in any clear sky.  A slight realignment of the high could start bringing something a fair bit colder still, not sure any snow just yet as the uppers around the high don't look conducive..  

Over to the 06Z to see if it strengthens the idea!!

Yes Ali, looks like cooling nicely. I'm surprised there isn't more excitement this morning. GP hinted at this turnaround yesterday and the other pros have been sticking to their guns. Colder blocked second half of December looking to be on track.

[fergieweather]

UKMO point-out the increasingly bimodal distribution of members in ECMWF Monthly by week 4. This explains the sudden appearance of bland temperature anomalies into that lead time, through a process of cancellation. Interestingly, latest GloSea5 also goes bimodal into same period, with the result that both above and below avg temps are signposted as more likely than climatology and confidence remains very low.