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

[Iceaxecrampon]

Why did I have to look?

Temps dropping as from a week from now - some potential ice days and the perma frost will be setting in....!

 

[Frosty.]

8 hours ago, Banbury said:

close off December and hope months 2 and 3 are filled with something , though aren't they the months the PV is to get going

Yes, we still have that to look forward to

[Scandinavian High.]

I don't think models look to bad south east of uk looking calm dry frost as move further on. The north west looks little more unsettled at times with a south westerly but south westerly never gets in to the south east so it's north west / south east split. Then Christmas period looks like there's a battle ground no snow yet .  But low to west high to east maybe some colder air coming in from east I think this much better then last December endless storms the meto have had this nalled still got plenty of time for for cold and snowy surprises if there was any cold with snow on way I bet meto would be first to see  long before we do I could be wrong on that but as for me love trying to forecast the weather.

[Faronstream]

The AO value the coming 10 days is still very doubtful but 60% of them wants it to get even more positive and 40% on the colder side, still no real signs of any real cold or powerful high pressure around my area or  the north Atlantic. Something tells me this will be the 4th green christmas in a row

[Matthew.]

I really hope the tropical forcing is the same pattern in summer let's hope ENSO has a gradual El Niño next year and the zonal winds play ball. At least the ECM shows the dry scene continuing for now with LP well to the north baroclinic line.

[Summer Sun]

 

[tight isobar]

Once again Im 'somewhat' encouraged by output going forward tbh.

Orientation/placement of HP' is far from resolved from midweek and certainly beyond.

Its micro scale globally yet massive for our part.some small alignment s and its a world of difference to our meteorology on all basis' s.

I have a gut feeling that in 2/3 days the models (cross) couls swing the pendulum in favor of significant differences in our part for something less benign' and something far more favorable! 

[bluearmy]

4 minutes ago, Summer Sun said:

 

And glosea ! (Apparently)

[Summer Sun]

UKMO at D7 looks to have some rain for some parts of the south dry elsewhere

Edited December 11, 2016 by Summer Sun

[Captain Shortwave]

6 minutes ago, Summer Sun said:

 

That's how I see it too;

      

It looks like we will get a strong enough build of heights to push fronts away from the UK, we would likely see an unconventional NW/SE split with the coldest weather in the south east with milder south westerlies in the north west. Uncertainty begins around day 9/10 when the next Atlantic trough approaches and again it seems the ECM ens flatten the pattern whilst the GEFs seem more keen on the high to hold firm. How cold and how widespread this gets is uncertain but temperatures by the end of next weekend could very well be falling to low/mid single figures in the south.

Edited December 11, 2016 by Captain Shortwave

[Cleeve Hill]

54 minutes ago, abbie123 said:

I don't think models look to bad south east of uk looking calm dry frost as move further on. The north west looks little more unsettled at times with a south westerly but south westerly never gets in to the south east so it's north west / south east split. Then Christmas period looks like there's a battle ground no snow yet .  But low to west high to east maybe some colder air coming in from east I think this much better then last December endless storms the meto have had this nalled still got plenty of time for for cold and snowy surprises if there was any cold with snow on way I bet meto would be first to see  long before we do I could be wrong on that but as for me love trying to forecast the weather.

That is a good looking chart, with the high over Scandinavia drifting west and the trough looking to slip south east. Potential in that one ! 

[northwestsnow]

2 minutes ago, bluearmy said:

And glosea ! (Apparently)

Blocked sounds good to me blue, i assume eps and gefs have the jet roaring away somewhere between scotland and iceland.We DESPERATELY need some help in the Atlantic sector down the line or the block will sink eventually, looking for some GP input wrt mjo etc ..

[Man With Beard]

1 hour ago, knocker said:

Looking at GFS det run and the GEFS anomalies thus morning indicates (to me anyway) a drift towards the ecm and less, or none at all, blocking. However there still so much uncertainty about the evolution best just put in the pending file.

Could be true in the long term. Interesting that the GEFS trumped the ECM ens completely in the current T168/T192 period - ECM consistently had a flatter pattern before this weekend, while GEFS had strong high pressure nudging into the SE. Models now adopting the GEFS position and strengthen it further. The signal of a 1030mb high has proved a significant signal again.

Edit: SS and BA you beat me to it!!

And yes I have taken note - Glossea's forecast for blocking mid-December looking good. Another instance where Glossea has got it right* 2-3 weeks out. Impressive! (*Assuming it works out!!!)

Using the same theory of looking for the 1030mb mean high, we see by D11 that the high is sinking into Europe

Suggesting either a return to a SWly influence, or possibly a continuation of continental influence for England/Wales if the high maintains even greater strength. But very low chance of snowy cold by this stage.

Edited December 11, 2016 by Man With Beard

[Summer Sun]

Having gone on a snow hunt of the GFS 00z I've found these

Edited December 11, 2016 by Summer Sun

[Banbury]

6 minutes ago, Summer Sun said:

Having gone on a snow hunt of the GFS 00z I've found these

Your not a bad bloke after all Gav  

[johnholmes]

The anomaly charts are pretty consistent over the past 3-4 days. That is in all starting to show that the centre of the upper high/ridge with its centre of gravity will be in the area of southern Norway. Even NAEFS suggests this at 240h. So to me that is the most likely upper air pattern from about day 4/5 out to at least day 15/16 possibly beyond.. The position of the surface feature is unlikely to be hugely different I would suggest. Near enought for the surface drift to be from SSE-east perhaps, so cloud cover could be a problem for some parts. Temperatures on the 'cold' side especially at night with cloud breaks. Perhaps some fog. Not much if any rain, apart from the NW of the country, little chance of any snow.

charts below

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

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

http://www.meteociel.fr/modeles/naefs_cartes.php?code=0&ech=240&mode=0&map=1&runpara=

[northwestsnow]

1 hour ago, knocker said:

Looking at GFS det run and the GEFS anomalies thus morning indicates (to me anyway) a drift towards the ecm and less, or none at all, blocking. However there still so much uncertainty about the evolution best just put in the pending file.

Hmmmm, not according to matt hugo, not saying you are wrong but he is suggesting the opposite!

[bobbydog]

Just out of interest here is what the UKMO was predicting for today, 5 days ago.

And the GFS 5 days ago-

And the ECM 5 days ago

And today's actual chart-

Edited December 11, 2016 by bobbydog

[Man With Beard]

9 minutes ago, northwestsnow said:

Hmmmm, not according to matt hugo, not saying you are wrong but he is suggesting the opposite!

I think Knocker is looking further ahead than Matt

[northwestsnow]

2 minutes ago, Man With Beard said:

I think Knocker is looking further ahead than Matt

No idea, he said gfs\gefs have moved to ecm with little or no blocking, matt just tweeted something along the lines of looks like gefs were right and eps now look blocked?

[IDO]

7 minutes ago, northwestsnow said:

Hmmmm, not according to matt hugo, not saying you are wrong but he is suggesting the opposite!

I think we can get lost in the anomalies and the reality. For instance the D10 ECM mean anomalies suggest close to a Scandi HP, yet in reality its the continuation of the Euro High:

To me that is not a block per se and although the further SE you are the greater influence from the continental drift, the jet is running to the north UK bringing in milder temps and rain. Same for the GEFS mean:

The Euro high stretches its reach further NW on this D10 mean.

So surface cold but as for wintry potential it remains a poor setup for snow & even real cold uppers, just inversion and continental flow. 

[karlos1983]

Did I really just read that right? GLOSEA5 and EC now going for blocking!  

[northwestsnow]

3 minutes ago, karlos1983 said:

Did I really just read that right? GLOSEA5 and EC now going for blocking!  

Yes, but not high latitude blocking...

Edited December 11, 2016 by northwestsnow

[swfc]

becoming a bit of a borefest now the model and nhp output.its amazing once this set up is in place that you almost know whats coming before you check the models!!id love to hear from some of the pros ete how or when they think a change arrive???.

[johnholmes]

from IDO

I think we can get lost in the anomalies and the reality. For instance the D10 ECM mean anomalies suggest close to a Scandi HP, yet in reality its the continuation of the Euro High:

Perhaps you are getting hung up on definitions. When is a .... high a such and such?

The main feature, and a consistent one of the 500mb anomaly charts is where the centre of gravity of the upper high is predicted to be.over sw Norway not central Europe, see the Met Fax chart for its current position. Perhaps not unlike the Azores high, which with the right upper air conditions moves to Scandinavia.

The end result will be little rain (or snow for that matter) away from the NW of the country, frost and perhaps some fog at night depending on cloud cover. Temperatures below normal, again depending on overnight cloud cover, perhaps down to the official 'rather cold' category.

My take of course, your take is just as valid, but it is rather like an old record IDO, it plays the same tune as you do try and distort what the models say to give a 'mild' slant, usually not always.