Model Output Discussion 4th Dec.2013-12z onwards.

[shedhead]

The models continue to show more conventional zonality driven by the deep PV over Greenland. Increasingly wet, windy and unsettled, generally mild at times and likely to dominate for some time.

Morning Ian...succinct but pretty much spot on based on the overnight suites, which remain dire for cold prospects. The only interest in the run up to Christmas and probably across the period itself looks set to be some stormy conditions if the pattern eventually shifts far enough SE, but as far as anything wintry is concerned the wait goes on....perhaps now into Jan if SK's post re the ECM32 is concerned...

Edited December 10, 2013 by shedhead

[Frosty.]

The GEFS 00z mean is a lot more unsettled looking at the various timeframes of T+168 / 240 & 384 hours, especially for the northwestern half of the uk, as you would expect, there is some ebb and flow between the high pressure to the south / se and low pressure to the west / nw but low pressure appears to have strengthened it's position compared to recently.

[Frosty.]

Nice to see the Gem 00z looking much more unsettled as time goes on with the PFJ digging further south, the limpet euro high might not be such a limpet after all, at least as far as the uk is concerned anyway..

[phil nw.]

Morning Ian...succinct but pretty much spot on based on the overnight suites, which remain dire for cold prospects. The only interest in the run up to Christmas and probably across the period itself looks set to be some stormy conditions if the pattern eventually shifts far enough SE, but as far as anything wintry is concerned the wait goes on....perhaps now into Jan if SK's post re the ECM32 is concerned...

 

Yes as we thought this south.westerly type of pattern tends to stick around for some time once established.

The 00z outputs continue with this theme with a trend in later mean outputs to ease the more unsettled conditions further south.

 

We may well see some brief colder interludes affect areas further north from this trend later but certainly nothing Wintery apart maybe the Scottish highlands.

The ens graph do show things trending towards average later but really nothing to suggest a step change to a different pattern currently.

[Gibby]

Good morning. Here is the report on the midnight outputs of GFS, UKMO, GEM, NAVGEM and ECM for today Tuesday December 9th 2013.

 

All models show a mild Southerly flow over the UK between High pressure over Southeast Europe and Low pressure over the mid Atlantic. The mildest conditions are shown towards the NW where Southerly breezes will be at their strongest with a little rain at times. In the SE drier continental air may filter across over the next 24-48 hurs bringing slightly less mild air and a greater risk of mist and fog overnight for a time. However, by the end of the week and into the weekend troughs make more progress across the UK bringing at least a short spell of rain and stronger winds for all before things dry up and settled down somewhat again over the second half of the weekend as High pressure is shown to build back North to some degree from the South.

 

GFS then shows a very mobile pattern next week and on until Christmas with the details irrelevant. With a train of Low pressure crossing quickly over or just to the North all areas can expect wind and rain and there will be quite a lot at times on Western upslopes. Winds will often be strong but always from a mild SW'ly direction continuing the no risk of wintry weather going for all areas.

 

UKMO today shows a return to this weeks synoptics early next week with High pressure refusing to move away from NW Europe with Low pressure out to the NW with a broad and very mild SW flow carrying rain at times to Northern and Western areas while the South and East maintain a lot of dry weather.

 

GEM today continues it's trend from yesterday with mild SW winds blowing strongly across all areas next week. Troughs and smal depressions in the flow will move rapidly NE over the North at times with some fast moving spells for all with the heaviest rain as usual towards the north and West with some drier interludes more likely towards the SE.

 

NAVGEM this morning holds the main thrust of Low pressure further to the NW and as a result High pressure remains close to the South and SE and although a few weak troughs deliver a little rain in the South at times the main share of Atlantic rain will be across the NW with mild conditions persisting everywhere.

 

ECM shows the weather becoming more deeply unsettled and often wet through the middle and end of next week with Low pressure troughs digging South across the UK delivering spells of rain and showers in blustery and mild SW winds. Things are shown to feel less mild later as winds switch more towards the West or even a little north of West at times when showery interludes could include a little wintriness over Northern hills.

 

The GFS Ensembles today show a few more dry days before things steadily turn more unsettled and often wet in the North and West but less so in the SE. This pattern is very indicative of a normal winter pattern of deep Low pressure to the NW and High to the SE with troughs crossing NE over all areas at times, most active towards the NW. Upper temperatures will fall off from current levels to nearer average ones later but at the surface some very mild days could be enjoyed in the SE Especially and to the lee of high ground in the NE. There looks absolutely no sign of anything remotely wintry from any ensemble member other than the odd one or two this morning.

 

The Jet Stream maintains it's trend to sink SE over the next few days to be running still in a NE direction across the Atlantic but this time over the UK allowing Atlantic lows and fronts to make deeper inroads into the UK. The trajectory though remains totally unbeneficial for getting any sort of cold anywhere near the UK due to persistent High pressure over SE Europe.

 

In Summary the trend towards more unsettled but still very mild weather is gathering some pace this morning. However, it looks unlikely that the SE will see too much in the way of rain but the North and West could become quite wet at times. Winds will also become more of a feature for all areas, blowing from the SW strongly at times with gales or severe gales in places and maintaining temperatures average or above for all. As we move inexorably towards Christmas day by day the chances of anything Wintry over the UK on the big day look distinctly remote from today's trend and synopses.

[cyclonic happiness]

I'm more optimistic now than I was when FI was full of epic winter charts.

 

Yes the polar vortex is sitting on Greenland and yes it got us stuck in southwesterlies.

 

But, weren't some of the best winters in Britain preceded by some 'really' warm weather?

 

Also, I still believe the saying that we get what America's getting but two weeks later (don't bother telling me I'm wrong, are you able to resist the urge??).

 

The ECM shows a surge of highs towards Scandinavia, whether it will stay there or not, or whether it's flattened off again, we'll just have to wait and see.

 

We'll get it guys and better than ever.....mark my words :-D 

[Frosty.]

The Gfs 00z op run becomes generally unsettled with rapidly alternating airmasses between tropical / polar maritime and occasionally an oceanic north atlantic flow with some stormy spells as vigorous lows sweep in off the atlantic, IMO it's much better than boring stagnation as per this week, looking forward to the winds and rain.

[johnholmes]

Certainly there have been quite marked changes over the past 5 days on the ECMWF-GFS 500mb anomaly charts but less marked so far with NOAA. Five days ago all 3 showed the upper ridge close by the UK to be the dominant feature with the main trough way west around 30 and as far as 40 west on them. This morning we see the major trough within the 10-20 west area, even closer on one and the upper ridge less dominant by far, and a bit further east and less marked. Some indications of +ve heights developing in the Azores area and a shade north of there. See below. NOAA still less inclined to show a similar idea but it too (both 6-10 and 8-14) has shown some considerable changes in emphasis. Overall I think the idea of a more unsettled Atlantic weather type is the way the models are going. Slowly this will extend to all parts and with the strength of the indicated 500mb flow then there is scope for a fairly active set of lows coming across the Atlantic. How long that may last I have no idea.

http://www.meteo.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

Edited December 10, 2013 by johnholmes

[EML Network]

Even the ECM is getting fed up with the never ending droll pattern of nothingness and kisses goodbye to it by giving it the finger

 

Edited December 10, 2013 by EML Network

[Purga]

Happy Christmas

Nice for the SE

[shedhead]

Clearly a long way out, but GFS still wants this Icelandic beast to push somewhat colder, more seasonal conditions S in the week before the fat man arrives..

 

[Newberryone]

Even the ECM is getting fed up with the never ending droll pattern of nothingness and kisses goodbye to it by giving it the finger

 

So glad to see the overall pattern change gaining momentum and long may it continue 

[shedhead]

So glad to see the overall pattern change gaining momentum and long may it continue 

Might be a case of be careful what you wish for though....not sure a major storm right on Xmas would be on many peoples 'must have' list.

[Newberryone]

Clearly a long way out, but GFS still wants this Icelandic beast to push somewhat colder, more seasonal conditions S in the week before the fat man arrives..

 

Please don't tell me you're referring to an azores/euro high?

 

Phew..Santa of course 

Edited December 10, 2013 by Newberryone

[shedhead]

Please don't tell me you're referring to an azores/euro high?

No unless the AH has a white beard and wears a big red outfit....

[mulzy]

6z GFS pretty zonal after 120 hrs though there are height rises in FI to the NE but these get blown away by a strong PFJ.

 

 

Looking at the whole model suite, no major changes from last night;  unsettled (with average to above average temperatures) run-up to Xmas looks the form horse.

Edited December 10, 2013 by mulzy

[itsnowjoke]

These posts are confusing they seem to contradict each other ?

[Mucka]

ECM London ensembles.

 

 

In all honesty it would be hard to find a worse set for cold prospects.

It's a case of grin and bear it for coldies I'm afraid.

[jvenge]

These posts are confusing they seem to contradict each other ?

Because there are 5 or so different models, which rarely agree completely quite far out. Then we have the fact that a lot of people have a bias towards either cold or mild, which comes across in their views of the models. Also, most are just keen ameatures here, so they will get it wrong. If the last 5 pages tells you anything, its that things can change quickly and that many people who post here arent objective. :-)Dont stress it and just take it for what it is.

[gottolovethisweather]

Hello, I had this to say only three days ago on here and hopefully it is a plausible outcome, having watched the GFS 6z unfold.

 

"I feel a change in general NWP output will rear its head sooner than some many well believe. Tuesday/Wednesday's runs will reveal more, however that is simply my gut feeling."

 

Its not always recommended putting too much emphasis on one run and of course, I am only commenting on the GFS but the GEFS spread has been consistent for a wee while, as per my post below.

 

http://forum.netweather.tv/topic/78671-model-output-discussion-4th-dec2013-12z-onwards/?p=2857988

 

Furthermore, UKMO are slowly hinting at the same and we will need to closely watch their output over the coming days to see if it is indeed a plausible option for the week before Christmas. The GFS love-in with the nearby HP cell may finally be a diminishing signal.  The ECM 0z review posted by Frosty earlier today, see below, also hints at a change nearing the reliable, so at last some movement away from the static pattern.

 

http://forum.netweather.tv/topic/78671-model-output-discussion-4th-dec2013-12z-onwards/?p=2858964

 

An initial SW'rly driven flow firstly then possibilities of PM incursions thereafter is how I currently see things. Tread carefully for now and maybe our coldie's patience will be finally rewarded as we head into the last ten days or so of December.

Edited December 10, 2013 by gottolovethisweather

[itsnowjoke]

I get the the models throw out different weather senarios and people are bias ie cold mild but i wish people would just post facts instead of me reading pages of... "Winters over" or "Merry Christmas" and post a flipping good chart which is far out in FI. I go from ney to yeah in about 12 posts very hard work when your trying to learn and your a coldie

[shedhead]

These posts are confusing they seem to contradict each other ?

I think the best way to simplify things is - increasingly unsettled, becoming mild/very mild for a time, then turning a bit colder later...but nothing in the way of proper cold as far ahead as we can reliably look.

Edited December 10, 2013 by shedhead

[gottolovethisweather]

I get the the models throw out different weather senarios and people are bias ie cold mild but i wish people would just post facts instead of me reading pages of... "Winters over" or "Merry Christmas" and post a flipping good chart which is far out in FI. I go from ney to yeah in about 12 posts very hard work when your trying to learn and your a coldie

 

Hopefully you read the post above yours then.

[gottolovethisweather]

I think the best way to simplify things is - increasingly unsettled, becoming mild/very mild for a time, then turning a bit colder later...but nothing in the way of proper cold as far ahead as we can reliably look.

 

A fair summary there shed, but I'm still waiting for the mild air down here in my patch, yes it will arrive shortly I suppose, hopefully along with a bit less cloud, but that last aspect is far from guaranteed. Changeable sums things up in the medium-term.

Edited December 10, 2013 by gottolovethisweather

[shedhead]

I get the the models throw out different weather senarios and people are bias ie cold mild but i wish people would just post facts instead of me reading pages of... "Winters over" or "Merry Christmas" and post a flipping good chart which is far out in FI. I go from ney to yeah in about 12 posts very hard work when your trying to learn and your a coldie

Posting 'facts' about something as subjective as model watching/interpetation is almost impossible. Would be very boring if it were otherwise to be honest.