Model Output Discussion 13/11/13 >

[Frosty.]

I can't see any mild weather on the 6z apart from before the cold spell and then in a few weeks time, it's a very cold run for the time of year.

06z is rather mild and wet for most in FI

 

 

 

 

 

Edited November 15, 2013 by Frosty.

[shedhead]

Well 24hrs can be a very long time in model watching, the last 24hrs has pefectly highlighted this fact and I suspect the next 24hrs will do much the same. No doubt the middle part of next week still looks cold, locally very cold, but the models all seem to be really struggling with the LP's coming out of Canada, which clearly has huge implications for the pattern post next Thursday. Frankly I've never liked the look of the Greenland pressure build touted and it now does look increasingly likely that the PV will win any battle up there, effectively killing the chances of a reloaded pattern. The best hope for cold does now look like coming from the east, but even if an east/northeasterly does set up things look set to be on the wrong side of marginal for snow. Whilst I wouldn't go as far as to say these synoptics are wasted at this time of year....nah sod it, they are wasted at this time of year...

Edited November 15, 2013 by shedhead

[Mapantz]

PS: Just to add to the above post:

 

Matthew Hugo â€@MattHugo81 3m

Latest EC32 maintains northern blocking or high pressure over the UK right through to the 15th of December. A distinctly 'un-zonal' pattern

 

It seems to me that it's not worth trusting that. I remember the last update he posted, saying the EC32  is showing unsettled conditions throughout November.  

Does anyone know if the EC32 is used in conjuction with the MO monthly outlook?

Edited November 15, 2013 by Mapantz

[Frosty.]

It seems to me that it's not worth trusting that. I remember the last update he posted, saying the EC32  is showing unsettled conditions throughout November.  

Does anyone know if the EC32 is used in conjuction with the MO monthly outlook?

yes with mogreps, the met office ensemble data and probably a blend of the others too depending on noaa discussions.

Edited November 15, 2013 by Frosty.

[LomondSnowstorm]

getting away from disecting each op run, having looked through naefs and ecm ens this morning, i am tempted to ramp. lets wait for a few more runs but the main themes to be taken are that the vortex relocates to siberia and begins to throw a trough into scandi whilst heights stay high to our nw. there are the first signs on the 850 spreads of a 'beast' heading sw from nw russia though it currently struggles to make inroads into the uk. finally, hints on naefs that in two weeks time we will see the atlantic pushing more forcefully into europe which promotes the chance of some late november events.  now back to worrying about if it will snow in my back garden next thursday morning at hald past ten........................................

Very encouraging signs indeed, I did notice that, in spite of the model variability in the medium term, the ECM ensembles this morning remain as promising as they were last night, if not moreso. The common theme from pretty much all the output is low heights remaining over Europe, blocking emerging to our north and a vortex weakening or splitting with most of the energy heading towards Russia. And that's after a not unsubstantial northerly next week which could yet deliver a decent fall for many of us - not bad for mid November!

[SnowObsessor90]

Can't say I'm all that surprised by backtracking  this morning, had a look at the archived charts for 2010 last night and signal for prolonged cold back then was as clear as anything, that's never really been the case this time around.

[johnholmes]

 

 

im not convinced this will lead to better in December.

which is not much different from some posts on here a month ago for November.

The truth is of course that no one knows, no matter who they are, with any degree of certainty.

In terms of to the end of November then nothing I see in anomaly charts, AO, NAO, MJO suggests that mild will be the main feature of the weather leading into December. Once in December then I do not pretend to be able to predict that far ahead.

Stop worrying about 6 weeks hence if you are a cold lover, enjoy whatever version of cold the weather actually gives this country. Some of you are never satisfied, I do wonder what you are like in 'real' life sometimes, be it at work, home, or school!

[Nick B]

Heads up to an excellent post in the Strat thread just now by Tamara, which may lend some credence to the idea that the type of synoptics we've been seeing in the last 24 hours just may be longer lasting into the winter.

[phil nw.]

From a cold pov we look like getting the very best we could expect from a ridging Atlantic high next week.

Normally these topple over after a day or 2 leaving the UK back in south westerlies but not this time it seems.

The cut off Euro trough keeping the high just far enough north to maintain our surface cold after the initial cold northerly dies away.

 

Warks 2m temps indicate below normal temperatures right to the end of the period.

 

Snow over the north and some of the high ground further south with night frosts for many.

Modeling over the last 2 days have certainly trended colder with no sign of the Atlantic coming back in as we look in to week 2

 

NAEFs and ECM day 10 Anamols.

 

The colder pattern still apparent as we go into the last few days of the month.

[BeastFromTheEast]

Hi There, 

 

Just wondering does anyone know what model XCWeather uses? As they are usually pretty good with wind speeds and directions, although often the weather they forecast on their 7 day outlook generally seems to occur a couple of days sooner than originally indicated? They are showing sustained Easterlies from Thursday onwards but with still relatively warm temps 4-8..is that due to the current temp of the North Sea?

 

Thanks S

 

please remove if in the wrong thread, just not sure where to put it..thanks  

[johnholmes]

Hi There, 

 

Just wondering does anyone know what model XCWeather uses? As they are usually pretty good with wind speeds and directions, although often the weather they forecast on their 7 day outlook generally seems to occur a couple of days sooner than originally indicated? They are showing sustained Easterlies from Thursday onwards but with still relatively warm temps 4-8..is that due to the current temp of the North Sea?

 

Thanks S

 

please remove if in the wrong thread, just not sure where to put it..thanks  

 

GFS

[Pennine Ten Foot Drifts]

.............

Normally these topple over after a day or 2 leaving the UK back in south westerlies but not this time it seems.

..............

 

Not sure if I'm imagining it, but it feels as if over the last few years the tendency has almost been to favour retrogression to Greenland over topplers ? (which previously for a long time were by far the more common scenario). Or maybe because retrogression happened so rarely previously, the fact it's happened at all over the past few years makes it seem as if it's more common ? I don't suppose there's any actual stats which could back this up ?

[Methuselah]

Please, once and for all, cut out the snide comments? Including the 'clever' ones...

[shedhead]

Very good agreement within the 06 ensemble suite for the cold/very cold spell around 19-21st Nov, but by the 23rd the op becomes one of the coldest members, with plenty more 'milder' options on offer by then. Once again in FI the op is never a million miles from the mean, reflected by the fact there are roughly equal numbers of milder and colder options.

 

 

[phil nw.]

Not sure if I'm imagining it, but it feels as if over the last few years the tendency has almost been to favour retrogression to Greenland over topplers ? (which previously for a long time were by far the more common scenario). Or maybe because retrogression happened so rarely previously, the fact it's happened at all over the past few years makes it seem as if it's more common ? I don't suppose there's any actual stats which could back this up ?

I havent seen any stats on that PTFD but the days of the  jet screaming ne between Iceland and Scotland seems much less common these last few years.

The jet has appeared much further south,and prone to more buckling- certainly makes for much more exciting model watching for Winter lovers .

I did do a re-analysis of NH Ht.anomalies between recent decades and posted them in old Winter thread some time ago.These showed a more negative -AO/NAO tendency recently but unfortunately i have since deleted those charts from my hd.

Maybe when i can i will try and redo them.

[Frosty.]

The GEFS 06z mean is showing a prolonged rather cold spell, very cold next week but then the coldest uppers relax and retreat but we are still left with rather cold low level air. It's coldest next week though with arctic winds plunging south and the PFJ going on holiday to southern spain / north africa for a few days of rest and recuperation. There is no sign of mild air returning, temps may eventually limp back towards average or remain just below and there is an ongoing risk of wintry reloads from the nw / n / ne, so next week brings the risk of snow in places, icy patches and widespread frosts, in other words.....WINTER

[MPG]

Very good agreement within the 06 ensemble suite for the cold/very cold spell around 19-21st Nov, but by the 23rd the op becomes one of the coldest members, with plenty more 'milder' options on offer by then. Once again in FI the op is never a million miles from the mean, reflected by the fact there are roughly equal numbers of milder and colder options.

 

 

Is there an example of an ensemble that shows the output consistantly at -5 for 5 days? Dont think Ive ever seen one.

[Cecil Hogmanay Melchett]

getting away from disecting each op run, having looked through naefs and ecm ens this morning, i am tempted to ramp. lets wait for a few more runs but the main themes to be taken are that the vortex relocates to siberia and begins to throw a trough into scandi whilst heights stay high to our nw. there are the first signs on the 850 spreads of a 'beast' heading sw from nw russia though it currently struggles to make inroads into the uk. finally, hints on naefs that in two weeks time we will see the atlantic pushing more forcefully into europe which promotes the chance of some late november events.  now back to worrying about if it will snow in my back garden next thursday morning at hald past ten........................................ 

Interesting Nickl, getting this low 'under the block' next week is critical now IMHO.

The pattern could go into 'lockdown' down the line IF IF IF we can maintain the low pressure anchored across Southern Europe.

Very exciting times coming up...

[Cecil Hogmanay Melchett]

Well 24hrs can be a very long time in model watching, the last 24hrs has pefectly highlighted this fact and I suspect the next 24hrs will do much the same. No doubt the middle part of next week still looks cold, locally very cold, but the models all seem to be really struggling with the LP's coming out of Canada, which clearly has huge implications for the pattern post next Thursday. Frankly I've never liked the look of the Greenland pressure build touted and it now does look increasingly likely that the PV will win any battle up there, effectively killing the chances of a reloaded pattern. The best hope for cold does now look like coming from the east, but even if an east/northeasterly does set up things look set to be on the wrong side of marginal for snow. Whilst I wouldn't go as far as to say these synoptics are wasted at this time of year....nah sod it, they are wasted at this time of year...

Hand on heart this will be a slow burner,guidance pointing to the PV relocating from Greenland,Icelandic/Scandy high will force the jet south and bye bye Greeny PV.

Thats how im seeing it anyway.

[shedhead]

Hand on heart this will be a slow burner,guidance pointing to the PV relocating from Greenland,Icelandic/Scandy high will force the jet south and bye bye Greeny PV.

Thats how im seeing it anyway.

Without question that is a possibility HD, but that's all it is, along with a range of other possibilities. Not suggesting the next 48-72hrs will completely clear the fog, but I think come Monday will should have a much better idea of the longer term prospects for sustainable HLB.

[MPG]

Without question that is a possibility HD, but that's all it is, along with a range of other possibilities. Not suggesting the next 48-72hrs will completely clear the fog, but I think come Monday will should have a much better idea of the longer term prospects for sustainable HLB.

Hi Shedhead, Giving support to the EC32 is the GFS, NAEFS & GEM 00Z ENS. All show high pressure to the N long term (25-30th Nov). What you think?

[Ian Brown]

Interesting Nickl, getting this low 'under the block' next week is critical now IMHO.

The pattern could go into 'lockdown' down the line IF IF IF we can maintain the low pressure anchored across Southern Europe.

Very exciting times coming up...

Are you feeling alright HD ? Seriously yes LP over Southern Europe will prevent a return to conventional zonality. It was hard to see where the METO were coming from a week or more ago with their call for below average temps but at times unsettled conditions especially for the Southern half but that looks where we headed post the Northerly.

[shedhead]

Hi Shedhead, Giving support to the EC32 is the GFS, NAEFS & GEM 00Z ENS. All show high pressure to the N long term (25-30th Nov). What you think?

Firstly I'm not a big fan of the ECM32, I still find it tends to mirror expected short/medium term conditions a little to often for my liking.  As for the others you mention the current support for higher pressure to the N definately exists, the problem I have at the moment though is the tenuous nature of the synoptics that first get us there and then try to keep us there.  It looks to me as if longer term HLB is kind of sat on a clothes line atm, nothing to say it can't stay there, but it could very easily fall off - so I want to see several more days worth of model data before I assume anything.

Edited November 15, 2013 by shedhead

[terrier]

Well whatever the future output holds for us i think this is pretty good to say were only in november. 

[Thundery wintry showers]

I get a sense that the GFS is rather overdoing those shortwaves for the 18th/19th, but the ECMWF/UKMO often underdo such features, so the most likely outcome is a middle ground between the two.  I'm expecting rain to fall on the southern and western flanks of the shortwaves, but sleet/snow is likely in heavier bursts on the northern and eastern flanks, which means that it will be particularly difficult to forecast who will get snow from them.

 

Snow cover may well be quite widespread in eastern Scotland and north-eastern England early on the 20th from east-coast snow showers working their way inland thanks to a slight easterly component to the wind direction, although there is a slight possibility of something like the ECMWF operational run coming off and the wind direction being revised to more of a northerly or even NNW'ly which would keep showers more confined to coastal fringes.  It may be cold enough for lying snow in East Anglia and Lincolnshire too, but for those regions the assessment is more sensitive to slight changes in the 850hPa temperature.  If the majority of model outputs are to be believed, though, a north-easterly flow is subsequently likely on the 21st and 22nd, with showers for eastern areas starting off as snow but probably turning back to rain/sleet as slightly less cold air mixes in from the south-east.  This is suggested by the change in minimum temperatures overnight:

 

http://cdn.nwstatic.co.uk/gfsimages/gfs.20131115/06/123/ukmintemp.png

http://cdn.nwstatic.co.uk/gfsimages/gfs.20131115/06/147/ukmintemp.png

http://cdn.nwstatic.co.uk/gfsimages/gfs.20131115/06/171/ukmintemp.png

 

In my experience the GFS often overdoes the warming effects of the sea near the east coast, especially for East Anglia, but the trend is clear.  So for snow lovers in the east the 20th is probably your best bet.

Edited November 15, 2013 by Thundery wintry showers