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

[Captain Shortwave]

ECM - ouch 

Worth noting the considerable differences between the GFS/ECM and the UKMO with regards to this Thursday

ECM

Stormy

GFS

Stormy

UKMO

Not even showing Gale force winds here. Non-event???

 

You just have to wonder here, the UKMO is not going for this one bit.

[That ECM]

ooooooo that looks nasty, at first I thought someone had spilled red wine all over the map.

Indeed and these have a tendency to trend a little further north as we get nearer to T 0.

[Dan the Man]

In all seriousness, if those charts firm up over the coming days for Christmas Day, there will be a lot of people not getting home for Christmas. Flights/trains cancelled again.

[radiohead]

It's not too late to add "a new roof please" to Santa's list.

 

[Frosty.]

In all seriousness, if those charts firm up over the coming days for Christmas Day, there will be a lot of people not getting home for Christmas. Flights/trains cancelled again.

I agree but if it was showing widespread blizzards, the forum would be in meltdown and that would also stop a lot of people getting home for christmas. flights/trains cancelled etc, wrong kind of snow etc..it's swings and roundabouts.

[alexisj9]

I hope the storm on the 25th doesn't move east like on todays ECM it looks very dangerous for the south. Here's the pic for the 26th those tight bars would have traveled right over us.

 

http://www.meteociel.fr/modeles/ecmwf/runs/2013121600/ECM1-240.GIF?16-12

 

If this happens the whole uk is in the firing line.

Edited December 16, 2013 by alexisj9

[EML Network]

Reading the Met Office's 6-30 day outlook's and you have to wonder if both the GFS and the ECM are overcooking the lows from the weekend onward, especially so the further south you go.

 

The constant message from them remains that the NW will see the worst of the weather and the SE is likely to be drier.

 

To me this suggests that they are seeing High pressure building back from the South to effect the South and Jet stream positioning itself further North than what the GFS and ECM are modelling it to be.

 

That being said the GFS has remained absolute (bar one run), over the past week especially so for the XMas period with pretty all of us experiencing a few days of very high wind speeds.

 

I for one would be gutted if we don't at least get one decent storm out of this, if it's not going to be cold than at least give us something , a plain old wondy day with rain and normal temperatures is about as bad as it gets.

 

On the up side the Ensembles are slowly starting to trend cooler in the UK and in parts of Europe toward the end of the runs, a trend that has been showing consistently now for some time, so here's hoping the new year will usher in something more seasonable.

[legritter]

Well gang ,looking at models charts ,we  may not have cold heaven But we certainly have Major weather events forecast for our island in what could become very newsworthy events .also an increasing risk of colder air being pulled into our shores .its all starting to get interesting and each day bringing even deeper Lows into our kneck of the woods .But the christmas /new year period still open for uncertainty in this very mobile pattern .

[Weather-history]

It's not too late to add "a new roof please" to Santa's list.

 

Not good if you are going to Midnight Mass in county Galway if it came off.

[fergieweather]

http://images.meteociel.fr/im/2906/ECF4-216_hes0.GIFAnd a merry christmas from the ECM this morning.

MOGREPS-15 has some similarities. All members for 25th deeply cyclonic but with much variation on the theme.

[georgiedre]

Bftp seems to think the models are firming up on a change to colder conditions as he's posted in the seasonal thread.

Just to touch more on my LRF before I do next months outlook, I am still very keen on the potential 'gamechanger' storm over NY period. I think there will be some substantial snow produced from this and may usher in a very cold period. Its coming within deep FI of GFS now...and some wild swings as one would imagine. Nice to see some PM and rPM air appearing with sub lows occurring now.

BFTP

[TSNWK]

MOGREPS-15 has some similarities. All members for 25th deeply cyclonic but with much variation on the theme.

Morning Ian - Just wondering if any of those variations on the theme might include some members dropping the trough further south & east during and beyond Christmas.

[BLAST FROM THE PAST]

 

Ouch!

My thoughts are that we are in a very active period now and this is plausible, but its all about timing......mind you I think later this week is worth looking at, particularly for W and NW.  So to sum up its batten down and watch 'now time' for developments.  A very wet period down here in he SE upon us, yellow warning issued by the MetO.....which is fine.... but its already upon us??

 

BFTP

Edited December 16, 2013 by BLAST FROM THE PAST

[Gibby]

Hi everyone. Here is today's account of the midnight outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Monday December 16th 2013.

 

All models show an unstable and relatively mild SW flow across the UK. This slackens off over the next 24 hours as a series of troughs finally clear the SE tonight. Then a 24 hour or so window of dry and bright weather with clear spells by night could give rise to the only frost of the week tonight in the North. Late tomorrow and Wednesday a new Atlantic storm winds itself up to the NW carrying renewed gale or severe gales to parts of Britain with rain sweeping East on Wednesday with colder and more showery air on Thursday when wintry showers could affect the North. On Friday, windy and milder air will return with more heavy rain with a rinse and repeat pattern of rain followed by showers looking likely over the coming weekend.

 

GFS then shows the run up to Christmas as unsettled and windy with rain at times. Conditions will be relatively mild in the South but colder at times in the North with wintry showers in between the spells of wind and rain. Christmas itself will be very windy and stormy across the NW as well as becoming generally rather less mild. Periods of rain look likely on Christmas Eve and Christmas Day followed by squally wintry showers across all areas later on Christmas Day and Boxing Day with gale force Westerly winds. The final days of the year are then typified by further rather cold and unsettled weather with an increasing risk of snow at times in the North as winds turn more NW'ly towards the New Year.

 

UKMO today ends next weekend on a windy and rainy note with an active and squally cold front crossing East next Sunday with heavy rain followed by rather chilly and showery WNW winds by night time.

 

GEM today shows High pressure building over Eastern Europe next week with winds backing Southerly or even SE'ly towards Christmas. With Low pressure ganging up to the West the Southerly flow would be very unstable with heavy rain moving North across Britain and more slowly East in temperatures close to average.

 

NAVGEM keeps strong WSW winds over the UK in the run up to Christmas with spells of rain alternating with showers, wintry in the North.

 

ECM keeps things very mobile and stormy at times with Christmas Day looking very worrying as an unusually intense Low near the Hebrides through the Day would bring damaging storm force winds to the West and NW in a spell of very heavy rain followed by squally and wintry showers before things moderate somewhat over Boxing Day.

 

The GFS Ensembles show a very turbulent period of weather over the next few weeks taking us through Christmas and up to the New Year. There is plenty of rain shown by most members throughout the period with the pattern having changed little 14 days from now. There is no indication of any fall off in uppers to levels that would give us anything more wintry to look at though in the colder polar maritime incursions over the next few weeks some short-lived snowy surprises could occur at times especially in the North.

 

The Jet Stream remains very strong exiting the States and crossing the Atlantic on a collision course for the UK for this week and probably next too with little sign of any major shift of axis and strength to get us out of this very volatile weather pattern.

 

In Summary it's more of the same today with plenty of wind and rain the talking points of the weather over the 2 week period. There is some output that worryingly suggests a powerful storm system near the UK over Christmas itself with the potential for disruption from strong winds and heavy rain over the period should it evolve as shown. However, rain and gales look like occurring with frequency throughout the period and it will be cold enough at times for some wintry showers as the storm systems recede away each time, only to quickly be replaced by milder and wet weather once more. GFS does show a more NW feed at the end of it's run prolonging a colder and more showery phase at the end of it's output but this is a long way out and to be honest there is little evidence of any pattern shift to what we have now when looking at those charts that go out to 10-14 days from now.

[Frosty.]

There is constant chopping and changing of airmasses and weather type on every day of the Ecm 00z op run, colder and showery one day, milder, wet and windy the next, drier, brighter and calmer and then milder, wet and windy again, also potential for stormy weather and I think the middle of this week is one to watch, and then again next weekend and potentially the middle of next week too. As for the risk of snow, thursday and overnight into friday looks cold enough for snow showers across hills and for overnight frost and icy patches, and then the same goes for next sunday. There is no end in sight to the turbulent pattern and potent lows, just small gaps separate us from the next stormy atlantic system so it's batten down the hatches time for the next few weeks. 

Edited December 16, 2013 by Frosty.

[R.P. McMurphy]

 

Ouch!

My thoughts are that we are in a very active period now and this is plausible, but its all about timing......mind you I think later this week is worth looking at, particularly for W and NW.  So to sum up its batten down and watch 'now time' for developments.  A very wet period down here in he SE upon us, yellow warning issued by the MetO.....which is fine.... but its already upon us??

 

BFTP

 

Hi BFTP,

 

It's certainly looking like a horrible period coming up over Christmas, wet, cold & windy - Couldnt get any worse !

 

Just touching on your point regarding the W / NW -  Why do you think this is? I don't see much besides a lot of rain & it extremely windy, and perhaps wintry over hills..

 

Cheers,

[Summer Sun]

The ECM ensemble has the low at 965mb with the centre around Iceland

 

 

The Op which has the most extreme solution

 

[R.P. McMurphy]

The ECM ensemble has the low at 965mb with the centre around Iceland

 

 

The Op which has the most extreme solution

 

 

The OP has it at 940

 

Travelling on Christmas Day is going to be a worry.

[Chris W]

(Edit - sorry, this is a quote of Summer Sun's post which I seem to have messed up a little)

 

(Quote)

 

The Op which has the most extreme solution

 

 

(End quote)

 

My word, that would be phenomenal in terms of meteorological interest but best if it does not happen.  I like stormy, but that would not be a nice Christmas for many.  My instinct is that it is over-egged, but will still pack a punch.

 

After that I see the GFS hints at a northerly toppler - anyone's thoughts on the Christmas-New Year interval for some bona fide wintry weather?

Edited December 16, 2013 by Chris W

[legritter]

 

(Edit - sorry, this is a quote of Summer Sun's post which I seem to have messed up a little)

 

(Quote)

 

The Op which has the most extreme solution

 

 

(End quote)

 

My word, that would be phenomenal in terms of meteorological interest but best if it does not happen.  I like stormy, but that would not be a nice Christmas for many.  My instinct is that it is over-egged, but will still pack a punch.

 

After that I see the GFS hints at a northerly toppler - anyone's thoughts on the Christmas-New Year interval for some bona fide wintry weather?

 

MY Current thinking looking at the models is it would only need some medium adjustments ,and considering this period is at the 10/15day range who knows ,and mother nature is very much alive in our neck of the northern hemisphere so all to play for .

[Summer Sun]

If you think ECM is bad enough for Christmas day take a look at GFS

 

 

A closer look shows a 935mb low just north of Scotland

 

 

The GFS ensemble has a 940mb low

 

 

On the other hand we have GEM which has backed away from a Christmas day storm this morning

 

 

Instead it looks like boxing day could see some stormy weather

 

 

Notice as well GEM has pressure building to our east

[BLAST FROM THE PAST]

Hi BFTP,

 

It's certainly looking like a horrible period coming up over Christmas, wet, cold & windy - Couldnt get any worse !

 

Just touching on your point regarding the W / NW -  Why do you think this is? I don't see much besides a lot of rain & it extremely windy, and perhaps wintry over hills..

 

Cheers,

Yes, extremely windy bit

 

BFTP

[shedhead]

Well it may not be cold and it may not be wintry, but it's certainly not boring either, with the overnight runs showing the potential for some genuinely stormy conditions right up to and even including Christmas itself. Clearly at this range detail will chop and change considerably, but it already feels like there is an air of inevitability about a big blow on the 25th, with this ECM 216hr suggesting the potential for widespread disruption/damage. 

 

[Nick F]

A look at the 00z GEFS and ECM ENS mean suggests troughing/low heights eventually spreading further south and east into Europe ... the 546 gpdm line (and the subsequently the jet) sinking further and further south as we head into Xmas week.

 

However, the core of the vortex still close to the north, so we will have to make do with some cold zonality - but this opens up the potential of transient snowfall for northern areas into the Festive Period, but there's also a continuing risk of some rather deep lows bringing stormy weather too. 

Edited December 16, 2013 by Nick F

[swfc]

big changes on the 6z ie the deep low has vanished at 192 hrs?pv looks to be weakening to a certain extent.Not sure if its a dodgy run but its a huge change

Edited December 16, 2013 by swfc