Model Output Discussion 1200 hrs 30/09/14

[Frosty.]

Interestingly the CFS monthly has been strong on a settled November anomaly with above average temps. Little sign of anything cold from them for a while:

 

cfs-8-11-2014.png  cfs-3-11-2014.png

 

JMA week 4 of October to end week 1 November suggests Uppers above average: Y201410.D0812.png

 

The GEFS mean in FI also showing seasonal average T850s for Aberdeen: MT8_Aberdeen_ens.png

 

The odd op run does show something a bit cooler like the 06z but the Control offers a milder perspective:

 

gens-0-0-312.png

 

So no real sign of any consistent sign of a cool spell yet alone anything cold but lots of uncertainty so things may change. Looking at the moment from week 2 a trend towards a westerly flow but not on full throttle so maybe brief ridges for the south for some drier weather. Late on in October signs are that pressure will rise and at least the S/SE/E should benefit from this.

At least it will be cold enough to snow on the top of Reigate hill

[Summer Sun]

WSI have done a write up using ECM's extended charts which we don't normally get to see, the charts cover the period of October 13th to November 9th

 

http://www.wsi.com/blog/energy/europe-ecmwf-discussion-13th-october-9th-november/

 

Well worth a look

Edited October 12, 2014 by Summer Sun

[Captain Shortwave]

UKMO still going for a southerly flow next weekend

It is though the outnumbered solution with the others going for a brief tropical maritime spell before the Atlantic gets back in with a bog standard westerly flow in tow.

ECM for example

The others overwhelm the ridge to our south east whilst the UKMO splits the flow and starts to develop a distinct low near the Azores.

It does look like longer term that lower heights might start to bear down on the Greenland region, we really need a ridge to our east and over the States to squeeze the life out of this and keep a slower moving pattern across the Atlantic. The last thing we need is for low heights to take up residence to our north west for a lengthy period of time.

[bluearmy]

the latter stages of the 12z ecm op are fascinating on a hemispheric level. plenty of WAA into the arctic beyond day 10 with subsequent further vortex disruption likely to follow. of course, its the op so just a throw of the dice at that timeframe. it does, however show, that with a negative AO in play, these mobile ridges can easily become something rather more solid within a fairly short timeframe.

[MP-R]

UKMO still going for a southerly flow next weekend

It is though the outnumbered solution with the others going for a brief tropical maritime spell before the Atlantic gets back in with a bog standard westerly flow in tow.

ECM for example

The others overwhelm the ridge to our south east whilst the UKMO splits the flow and starts to develop a distinct low near the Azores.

It does look like longer term that lower heights might start to bear down on the Greenland region, we really need a ridge to our east and over the States to squeeze the life out of this and keep a slower moving pattern across the Atlantic. The last thing we need is for low heights to take up residence to our north west for a lengthy period of time.

 

Though better now in mid October than in early December like last year right?

[Polar Maritime]

Yes Blue, The later stages of ECMWF continuing to show a disrupted Vortex as you say. And also hinting a Pm/rPm flow as per GFS recent runs.. The very last frames of GFS shows a possibility of a very Southerly tracking jet if Model continuation preceded beyond this point. 

 

[Captain Shortwave]

Though better now in mid October than in early December like last year right?

We really need to keep punching the cold air over the Arctic at the moment, the current positioning of ridging over Europe is helping to bring snow cover further towards the East of Europe. We saw a movement to a westerly pattern last year which halted this and inevitably never stopped until the beginning of March.

It doesn't really matter whether the slow moving trough is over us bringing wet weather or west/east of us, as long as we keep disrupting the developing vortex over the pole. That being said a true southerly draw would be very welcome, even at the point of the year.

ECM ens, still support milder weather next weekend, no point going further in description than that. It also concurs on the feeling that the main lobe will move/develop over northern Greenland which seems to be encouraging a more Atlantic dominated pattern for week 2

[knocker]

Last evenings 10 day and further anomalies are pointing the maintenance of a westerly flow over the UK with periods of unsettled weather with temps on the whole varying around the average.

 

Essentially at D10 we are talking cold air Greenland to eastern Europe with the warmer air running west/east south of this. Blocking ridge North America forcing the jet into a more SW/NE orientation. So low pressure high pressure split across the Atlantic and the exact latitudinal orientation of this will dictate the weather over the UK.

 

Further afield both the ECM and GEFs develop a trough in the Western Atlantic and weaken the extent of the warm air  Broadly speaking this results in an low pressure dominated Atlantic leaving the door open for some influence of HP from the SW. So remaining unsettled with nothing startling in the way of temps.

Edited October 13, 2014 by knocker

[bluearmy]

Another ECM op which delivers an interesting latter few frames across the polar field. Deducing which result is more likely is a needle in a haystack job but whilst heights across the Arctic continue to drop in line with the progression of the season, there remains plenty of encouragement that the pv will find it tougher to become organised in comparison to this time last year. That Arctic high remains our friend for the time being - coldies hope it stays around for a long time.

Edited October 13, 2014 by bluearmy

[Gibby]

Quiet in here this morning suggesting the models don't suggest anything interesting of note this morning.

 

HERE IS MY LATEST ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM 8AM TODAY MONDAY OCTOBER 13TH 2014.

 

NEXT UPDATE TUESDAY OCTOBER 14TH 08:00

 

THE CURRENT GENERAL SITUATION. An area of Low pressure near SE England will edge very slowly NE out into the Southern North Sea tomorrow filling slowly

.

MODELS-2 WEEK HEADLINE  Changeable weather with some rain at times but with some dry and very mild weather likely in the South and East for a time from later this week.

 

THE JET STREAM ENSEMBLE FORECAST The Jet flow to the South of the UK will edge further North on a SW to NE axis over the UK later this week before becoming a more organised and straightforward West to East flow across Southern England in Week 2 strong at times.

 

GFS The GFS operational today shows the current Low in the SE filling over the next 24 hours as a deep Low in mid Atlantic drives frontal troughs NE across the UK later in the week leading to a period of mild and strong SW winds and showers or rain at times especially in the North and West. Thereafter winds veer to a more Westerly point for a time with cooler and still unsettled, occasionally wet and windy weather for all parts. Late in this run High pressure returns to bring a more benign period to end the run with dry rather than wet weather becoming dominant with frost and fog at night as High pressure ends up centred across the UK.

 

THE GFS ENSEMBLES. The GFS Ensembles are broadly in agreement to the operational this week but differ next week in showing a very unsettled and potentially stormy period as deep Low pressure to the North maintains wet and windy weather alternating with chilly and showery weather lasting through to the end of the run with no significant pressure rise shown.

 

UKMO UKMO this morning shows mild SW winds bathing the UK at the end of this week. They will be unstable though with a frontal boundary likely to be lying across the UK somewhere and with pressure below 1015mbs everywhere some rain can be expected almost anywhere but as always in SW'lies more so to the North and West.

 

THE FAX CHARTS  The Fax Charts are fairly supportive of the raw data showing a mild and showery SW flow towards the end of the working week before a build of pressure brings a drier phase to the SE at the weekend. However, pressure is falling to the West and North and fronts from the Atlantic look likely to approach Britain from the West outside the time frame shown.

 

GEM The GEM operational today looks generally unsettled throughout with the mild SW flow later in the week giving way to Low pressure from the West  or SW settling over the UK for a time with showers and rain at times from the weekend in average temperatures but with some drier periods in between.

 

NAVGEM NAVGEM too shows a period of very mild SW winds and although a drier and perhaps brighter phase is shown for the SE generally unsettled weather will continue to bring rain at times to many Northern and Western areas in particular. 

 

ECM The ECM operational today continues the theme of very mild SW wins at the end of the week with some dry, bright and rather warm weather possible over the SE for a time before pressure falls somewhat and more unsettled conditions encroach across all areas from the West for a time under a shallow Low edging in from the West. The main Low pressure is however, steered quite a way North on this run which holds higher pressure to the SW which encroaches towards and over Britain later in the shape of a ridge bringing cooler and more benign conditions to end the run in the West.

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The trend is still towards the milder weather later this week being replaced by something cooler and still unsettled next week but the options are widely scattered within this general theme.

 

MY THOUGHTS  There  is one constant shown by all the output this morning and that is the weather is going to turn much milder later this week as SW winds are shown to move up over the UK from the Azores. These moist winds look like carrying a lot of moisture and Northern and Western areas could be quite wet at times but it still could be that the SE becomes rather warm and brighter for a time though this looks far from guaranteed by some output today. In any event all models then suggest a period when cooler Atlantic Westerly winds take hold lowering temperatures to average and continuing a theme of rain at times. It's from that point early next week that an array of options are shown ranging from a potentially wet and stormy period from the GFS Ensembles to something more moderate from ECM with High pressure edging back into the equation again by Day 10, this time from the SW. The GFS operational also takes a diversion off into high pressure land towards the end of it's 14 day run with if verified much fog and frost as a result. As all these options are the result of complex atmospheric upwind patterns shown for next week they are all viable but not guaranteed and as a result it is hard to predict where we will be synoptically in 10-14 days time. However, what is more certain is that there appears nothing out of the ordinary likely to come upon us suddenly over the next few weeks as the pattern seems like standard Autumn weather patterns currently none of which are showing any immediate slip into deep autumn or early Winter weather with just the usual bouts of windy and wet weather to contend with at times in broadly near to just above average temperatures.

[carinthian]

I hate this time of the year waiting for our first snowfall down to pasture levels. No sign of that looking at the latest models this morning. More of the same, warm  air mass , freezing level above 3000m. Last week saw one of the warmest Oct spells on record in Southern Austria with temps up to 80f in some places. A combination of hot sunshine and fohn effect .A bit cooler  this coming week but with the warmer than average temps likely to persist for the next 7 days at least.

C

[knocker]

The 10day Arctic 500mb anomaly. I must admit I always have trouble getting my barings with these

 

[Backtrack]

Certainly looks like a very warm weekend in the south. All of the hype over a cold spell which could materialize in two weeks time is completely over-shadowing what we have right in front of us.

 

How often is it we see 850HPA temperatures this high in mid-October. Temperatures could well hit 20-23C in the south should these charts come off. They are 6 days away, yes. But there has been a trend for this kind of setup over the last few runs, and it's certainly likely to be more accurate than cold spell dreams around the 22nd.

 

Imagine if that low was to move further west and flood the UK with uppers of 15C? They're pouring into Europe to give them one last taste of summer. 

 

 

Check out the temperatures in France there too, insane for this late on in the year! It'll be pretty windy though, even with the temporary ridge of high pressure.

Edited October 13, 2014 by Backtrack

[Altohumorous]

A warm fine spell around mid-October is very common in these islands, especially the further east you are. I can't recall the past couple of years but prior to that it occurred almost like clockwork.

[Bobby]

The ECM OP at day 10 is more settled than the ENS mean which has low pressure in charge. Also NAEFS.

 

 

 

 

The PV continues to build over Greenland so an active Atlantic and generally unsettled weather looks the form horse for the rest of the month, temps probably above average although some PM outbreaks possible.

 

Edited October 13, 2014 by Bobby

[Spikecollie]

Certainly looks like a very warm weekend in the south. All of the hype over a cold spell which could materialize in two weeks time is completely over-shadowing what we have right in front of us.

 

How often is it we see 850HPA temperatures this high in mid-October. Temperatures could well hit 20-23C in the south should these charts come off. They are 6 days away, yes. But there has been a trend for this kind of setup over the last few runs, and it's certainly likely to be more accurate than cold spell dreams around the 22nd.

 

Imagine if that low was to move further west and flood the UK with uppers of 15C? They're pouring into Europe to give them one last taste of summer. 

 

h850t850eu.png

h850t850eu (1).png

 

Check out the temperatures in France there too, insane for this late on in the year! It'll be pretty windy though, even with the temporary ridge of high pressure.

Not really insane! We had temperatures in the mid to high twenties in October last year and the year before over there - but it always end in fireworks. Looking forward to another little blast of very very late French summer next week!

[Polar Maritime]

Yes Bobby an unsettled outlook as you say, The 6z is showing Low pressure pushing a little further South by the 19th taking the High with it. So not Model'd as warm as in recent runs for the S/E. Some very moist air being pumped up off the Atlantic on a strong Jet to follow.

 

 

 

Edit: On a side note, Can we please stick to Model Output only in here.

 

Many Thanks, PM

Edited October 13, 2014 by Polar Maritime

[Man With Beard]

I'm not sure this weekend is going to amount to much on the basis on this morning's charts. Aside the ECM op we have the following for Sunday (the most likely day for warm/sunny weather):

 

The Atlantic is just too nearby. If warm seekers get lucky, a cold front may hold back towards the west coast/Irish Sea allowing a period of warmth on Sunday - but it may well be that it is only E Sussex/Kent/Suffolk that get an Indian Summer from this one. 23C is possible on the ECM op chart though.

 

After that, low pressure near Iceland seems certain to bring secondary Atlantic lows somewhere near the UK on a regular basis - so very normal Autumn weather, with a tendency towards the windier/wetter side I would guess, especially the further north and west you are.

[stodge]

http://modeles.meteociel.fr/modeles/gfs/runs/2014101306/gfs-9-150.png?6

 

One or two getting a bit carried away about this weekend's so-called "Heat wave". I would imagine 21c has been reached on any number of occasions in mid-October over the past twenty years and to be honest the 6Z Operational output doesn't look that brilliant for heat. What we don't know (but can suspect with experience) is that the fetch will bring in a lot of cloud and drizzle to south-west facing coasts so for the high temperatures we need to see cloud breaks and sunshine develop inland.

 

Simply having an 850 of 16c over us under cloud and drizzle means nothing - the synoptic set up may get us to 20c but without significant cloud clearance (and I don't know if we can predict that yet) we won't get much higher at this time of year.

[knocker]

http://modeles.meteociel.fr/modeles/gfs/runs/2014101306/gfs-9-150.png?6

 

One or two getting a bit carried away about this weekend's so-called "Heat wave". I would imagine 21c has been reached on any number of occasions in mid-October over the past twenty years and to be honest the 6Z Operational output doesn't look that brilliant for heat. What we don't know (but can suspect with experience) is that the fetch will bring in a lot of cloud and drizzle to south-west facing coasts so for the high temperatures we need to see cloud breaks and sunshine develop inland.

 

Simply having an 850 of 16c over us under cloud and drizzle means nothing - the synoptic set up may get us to 20c but without significant cloud clearance (and I don't know if we can predict that yet) we won't get much higher at this time of year.

 

Agreed. Assuming lapse rates is very precarious and often incorrect. Playing safe and using the EALR can still be way out.

[Nick F]

Have issued a synoptic outlook/discussion for the next 14 days - remaining unsettled but turning increasingly warm for a time this weekend, more especially in the south:

 

http://www.netweather.tv/index.cgi?action=news;storyid=6222;sess=

Edited October 13, 2014 by Nick F

[Yarmy]

Anyone having trouble viewing GFS charts on Meteociel? ECM, UKMO and others seem fine. Can't see any of the reanalysis charts either.

[phil nw.]

Anyone having trouble viewing GFS charts on Meteociel? ECM, UKMO and others seem fine. Can't see any of the reanalysis charts either.

It seems to be a problem on that site as I am getting the same result Yarmy.

Ours seem OK thoughhttps://max.nwstatic.co.uk/gfsimages/gfs.20141013/06/72/h850t850eu.png

If you want to view the GFS 06z run.

A good image of the approach of the tropical maritime air mid week.

[Yarmy]

It seems to be a problem on that site as I am getting the same result Yarmy.

Ours seem OK thoughhttps://max.nwstatic.co.uk/gfsimages/gfs.20141013/06/72/h850t850eu.png

If you want to view the GFS 06z run.

A good image of the approach of the tropical maritime air mid week.

 

Many thanks.

 

Edit: Working again, now.

Edited October 13, 2014 by Yarmy

[Polar Maritime]

A very disrupted Vortex on the latest GFS run, With strong Heights over the Poles. Some quite unsettled charts showing for the end of the Month, With severe gales for the North and very wet, It looks like the Atlantic gates are going to be bolted well back.

 

Edited October 13, 2014 by Polar Maritime