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

[mulzy]

Arctic high making a presence on the 18z - deep FI though.  Something to watch in future runs...

 

Edited December 20, 2016 by mulzy

[tight isobar]

Taking things on an evolutionary scale. 

Looking at Canadian/usa create and vortex lobeing' forcing zonality' even via one suite ie snaps) 18z gfs.

Its not hard to decipher the uphill climb for even MLB..let alone HLB at this given point. 

With an arche at western seaboard going forward' incurring eastern most seaboard depressed and scuppering development of evolution of any upserge of energyto alignment of possible Atlantic blocking.

This atm is an observation of earlly/mid term analysis. ..overall. 

We really need to view how any proposed form of heights building to the north/north east come into play with 144 hrs within the next 48hrs ..otherwise imo mobility/zonality. .are big ball player's. ..and are going for the premiership

Title...

[bluearmy]

Now that's a hemispheric fi of interest!

[Ravelin]

I don't believe no one has mentioned this, spot the difference on Xmas day...

12Z   18Z 

No real Xmas day storm for the north of Scotland. Turkey is back on the menu (assuming it doesn't come back on the 0z).

 

[Hotspur62]

1 minute ago, mulzy said:

Arctic high making a presence on the 18z - deep FI though.  something to watch in future runs...

 

And the PV moved more onto Siberian side on the latest GFS run.That is the positive but still not particulary low heights across the Med which has been the story so far this December. At least there are encouraging signs though

[Banbury]

A couple of frames later would have been of interest but far too DEEP into FI to get excited about.....................just yet

[stewfox]

47 minutes ago, Ravelin said:

I don't believe no one has mentioned this, spot the difference on Xmas day...

12Z   18Z 

No real Xmas day storm for the north of Scotland. Turkey is back on the menu (assuming it doesn't come back on the 0z).

 

Yes the second storm appears to have 'left' Scotland but still windy . That's a big difference in 24 hrs.

yesterday 18z 

Today 18z

Edited December 20, 2016 by stewfox

[TEITS]

2 minutes ago, bluearmy said:

Now that's a hemispheric fi of interest!

An increasing trend in my opinion.

This is what members should keep an eye on.

A straw to clutch onto which makes a nice change. Looking at the entire GFS run this instinctively looks the likely evolution.

[Man With Beard]

8 minutes ago, Ravelin said:

I don't believe no one has mentioned this, spot the difference on Xmas day...

12Z   18Z 

No real Xmas day storm for the north of Scotland. Turkey is back on the menu (assuming it doesn't come back on the 0z).

 

And quite a bit of snow for Scotland into Christmas night? Uppers -6 to -8, plenty of showers? High ground of Northern England likely to join in too.

[stewfox]

On 17/12/2016 at 18:16, stewfox said:

But the GFS is still holding onto some modified PM air and some places might get snow xmas eve into early xmas day

Ok the snowman wont be the best , but some may get a chance , if they start to build 2am xmas day before the mild air kicks in ?

Supporting pic attached

 

 

 Some  snow for Scotland into Christmas night and boxing day ? Uppers -6 to -8,  upgrade for  sure on tonights 18z GFS

 

-6c/ -7c -10c never too far away . Its brief so build fast

Edited December 20, 2016 by stewfox

[Banbury]

Hints of something going on over Greenland

[karlos1983]

7 hours ago, Iceberg said:

good update from Matt, hoped the ecm would show those solutions as we go into Jan  

ive just caught up on the afternoon shenanigans, one of the first posts I read is @Iceberg stating the potential, which I agree with. Much disagreement follows, not sure why, must be the winter of  discontent.... 

Ensembles look pretty darn good to me! Potential dare I blinking say it! 

 

Edited December 21, 2016 by karlos1983

[Banbury]

I guess this will have to do

Followed by some decent cold

This is all in the fun of the hunt I should add

[A Frayed Knot]

32 minutes ago, Banbury said:

I guess this will have to do

Followed by some decent cold

This is all in the fun of the hunt I should add

Now that's what you call Christmas *** Soz i Meant Winter

[knocker]

Firstly a general observation regarding this morning's GFS run and that is it fits very nicely within the indicated pattern of last night's anomalies in the ten day time frame as can be seen. I will skip any detailed discussion of the Friday depression as this no doubt will be adequately covered in more dedicated threads.

So straight on to Xmas day and the GFS is not developing this depression to any great extent, indeed it starts to fizzle out as it traverses norther Scotland, which of course is very good, so although there will a fair amount of precipitation ( a fair bit of snow on the hills of north west Scotland) and still be quite windy, certainly not destructive winds. Assuming this evolution is correct of course. The rest of the UK will gets periods of rain and showers in a strong westerly wind veering NW as the day progresses and temps initially a fair way above average in England returning to normal.

Immediately post Xmas Day sees the rapid amplification that has been signposted with the European high pressure developing rapidly with the trough stuck in the western Atlantic. thus heralding the start of a dry, quieter and relatively pleasant period of weather.

The surface high stays influential until T240 but it does slip south east which allows any systems struggling to move east to impact the north west of the country. No point in attempting any detail vis the weather at this range as it's rather dependent on the position of the surface high so generally, dry, no wind, temps possible a little below average with a fair bit of diurnal variability.

 

Edited December 21, 2016 by knocker

[IDO]

Not a lot to add to Knocker's summary really. The GEFS are mucking around with the waves of energy from the Azores as HP builds in the UK sector in the medium range. Variations on a theme as to the drift and flow of the high, It looks like it builds from the 27th and the mean only goes below 1030 hPa from Jan 1. So from a southern perspective:

After a mild Christmas Day, a contrast on Boxing Day and from then the temps dependent on inversion cold as the uppers remain well above the seasonal mark but 2m temps on the mean close to average. After Jan 1 the GEFS are a bit skittish and hard to gain any conclusions apart that the further south the drier you are and that there are a good cluster showing some cold uppers as far south as London. One to watch.

As for Christmas Day, the further south you live the milder and the drier, though cloudy rather than warm sunshine so that will dampen temps to 13c rather than higher. Very little precipitation for the next 16 days in my locale and thankfully the storms have been modelled further north as they near T0 (generally are with the GFS). so breezy in the south.

So good agreement till around the New Year then lots of uncertainty as to the PV -v- Azores 2nd wave.

[knocker]

The ecm has a different solution for the Xmas day depression but not the wind speeds and it looks like ant destructive winds will be to the north of Scotland although could well impact the Shetlands

Edited December 21, 2016 by knocker

[mb018538]

Let's hope the storm keeps the very worst of the winds out at sea. Either way, it's going to be a bit blowy oop north!

ECM comes up with a 192 hour chart that just makes me wish it was July again. At least it'll be calm, and staying pretty dry, especially in the SE.

[Frosty.]

Well, following an unsettled blip with some wet and windy weather, the Ecm 00z becomes gorgeous with high pressure taking a firm grip with pleasant days and chilly nights.

Edited December 21, 2016 by Frosty.

[bluearmy]

at least wind chasing seems to as prone to downgrades as cold chasing. I expect the hardy folk of the shetlands have had a few blowy Xmas days before! 

gfs/GEFS not looking keen to drop any idea that the Canadian vortex is going anywhere. At best it will head north of hudsons. Some trending towards split vortex and neg AO on the GEFS. geps not interested in that and will  probably only be clustering on the eps in that direction. 

Remaining interesting heading through week 2, nothing more than that. If this is a strong trend for winters ahead then maybe investing in Turkish skiing might be an idea! 

[nick sussex]

Did you all miss me? Lol Busy with friends here so not much time to catch up with the outputs which might be a good thing!

Having said that there's a brief window for the north later on Christmas Day to see something white falling from the sky.

After that high pressure close by and if thats centered to the east then this should pick up some clear conditions from across the Channel, so not too bad with some frosty nights and sunny days . The suggestion is that the high will eventually sink as the next round of jet stream on steroids piles east. 

The ECM tries to take some of the PV east with another high pressure cell building ahead of the upstream troughing, an opportunity at that point to perhaps develop something a bit more interesting but only if we can find some more amplitude upstream.

The GFS looks less interested with the ominous PV blob growing to the north.

Thats a way off , I do hope we can see some changes as we head into the New Year because chasing this Euro high around is now becoming tedious!

[Summer Sun]

Saturday is still looking nasty especially in Scotland with fairly widespread gales from Friday's storm

 

 

Christmas day the strongest winds gradually shift further south across England according to GFS

 

 

 

 

Edited December 21, 2016 by Summer Sun

[bluearmy]

If you live on the easter side of the states coldies can go from despair to joy within 48 hours, even on the normally reliable eps

look at day 12/11/10 from the last three 00z eps suites. These are upper anomolies. Might drive a mid Atlantic ridge but will also energise the jet. 

[Nick F]

52 minutes ago, bluearmy said:

Remaining interesting heading through week 2, nothing more than that. If this is a strong trend for winters ahead then maybe investing in Turkish skiing might be an idea! 

Or the Algerian Sahara?

Joking aside, 00z GEFS 500 hPa mean / anomaly chart indicates +ve height anomaly to the west which maybe a feature to look out for over coming runs.

00z EC and EPS heights and anomalies hint at this Atlantic ridging as early as  day 10 too

Could start to see more amplification in the upper flow work through from Pacific/N America as models now hinting at Aleutian / Alaska ridge reforming - perhaps in response to dateline ridging from tropical/MJO forcing.

Edited December 21, 2016 by Nick F

[northwestsnow]

3 minutes ago, Nick F said:

Or the Algerian Sahara?

Joking aside, 00z GEFS 500 hPa mean / anomaly chart indicates +ve height anomaly to the west which maybe a feature to look out for over coming runs.

00z EC and EPS heights and anomalies hint at this Atlantic ridging as early as  day 10 too

Unfortunately they show the euro slug persisting, this Euro high is a real bane and looking through the archives its a stand out in all the snowless winters of the late 80's etc, i really am of the opinion unless we see some SSW action, we are goosed...