Model Output Discussion 13/11/13 >

[shaky]

The GFS is now starting to smell the coffee.Some interesting synoptics, the pool of cold air does run out with nothing to draw on from the NE as we get to the end of hi res and into low res. This is usually always the case though, uppers will change with each run.The ECM will be very interesting!

ecm,gfs and the ukmo looking brilliant so far this morning.steve murr was right the gfs is playing catch up.i rememeber gfs doing that last winter aswell.

[radiohead]

Hmmm.

 

 

Edited November 14, 2013 by radiohead

[Beaufort12]

I haven't checked models since last winter but to my untrained eye the ECM looks pretty crap

[That ECM]

Hmmm.

 

 

The GFS has come on board. ECM at t 168 makes more of the energy coming from the nw. This makes building the pressure more difficult in that area. I think people should view nh profile as this enables you to see more. ECM is good but perhaps a little bit messy compared to GFS. UKMO at T 144 is wonderful.

[Mark Neal.]

The 00z Run from GFS, even showed a snow event for SW for next Tuesday night into Wednesday. To be taken with a pinch of salt but nice to see these charts showing at times however 

   

 

Some cold uppers in the flow.. See the Low pressure to the SW. 

 

Quick Search of XC shows this... http://www.xcweather.co.uk/forecast/BRISTOL  (Based on the GFS 00Z)

 

It doesn't have much support at this stage, so will probably be gone next run, but thought i'd share with you guys.

 

 

[Man With Beard]

Big picture wise, there is good agreement this morning at T144 for a rise of pressure towards Iceland and the tip of Greenland. After that, it's a close call on the energy coming off Canada, the models nearly agree but a little bit more energy on ECM today leads to HP building over us rather than above us. All models are quite cold, but how settled is up for grabs.

Excellent agreement for the first cold shot next Tuesday now.

Edited November 14, 2013 by rjbw

[bluearmy]

Maybe the coldest ECM run yet though it doesn't look as impressive. this shows the result if too much energy escapes over the top of the ridge. We saw ECM messing around with this a couple of days ago. Ukmo could go the same way post day 6. Still waiting to see a convincing direction of travel post the trough dropping south. only thing we know is it will be COLD.

[AWD]

I think people should view nh profile as this enables you to see more. ECM is good but perhaps a little bit messy compared to GFS. UKMO at T 144 is wonderful.

I was just going to say that the NH charts are much easier to read than those little zoomed in European ones as we can dissect the Atlantic pattern then, which ultimately in scenarios like this, is crucial.The EC Det, no questions about it, sends much more energy W/NW off the Eastern Seaboard preventing the high from getting as far north as previous runs have shown;This then causes the high to topple over the UK rather than to the north of the UK if it had ridged further north. It's a perfectly plausible scenario, one that fits in with some previous forecasts of a colder spell, not lasting too long before returning to something more average. No expectant GH!!!However, before hysteria breaks out in here one should consider the following.- Why should the 0z be any more correct than the 12z?- Where does the Det sit amongst it's ensemble suite?- What do other NWP models suggest? Does it resemble other NWP output?- How high were your expectations anyway?- What does teleconnective data suggest? How likely is the EC Det outcome?Anyway, off to work now. The EC Det still suggests a cold spell next week as per. It just doesn't have the longer term aspirations that many here were hoping for!

[Ian Brown]

ECM is a more realistic outcome following the northerly, the interesting thing is that low heights are maintained over Europe throughout the run. The GFS has done one of its sudden lurches that moves not only towards the other models but past them and must be treated with great caution.

[Captain Shortwave]

Well that low which develops in the western Atlantic is now going to start causing a real headache, worst still their effects are probably the worst things to be handled by the models. Either way the ECM does not deliver what many want, unless it is a prolonged period of dry weather with widespread frost and fog.

[Radiating Dendrite]

Model watching in winter is a bit like Total Wipeout! Once you get past one obstacle another pops up

As others have said, the ECM just seems a little too much energy over the top of the high. The cold spell for the start of next week looks pretty nailed on now.

Hopefully the ECM ensembles will paint a slightly more positive picture.

[phil nw.]

Yes model variation comes of the split flow and working out how much energy leaks under the block to hold it further north.

Whenever we get a high trying to build from the tropical side of the jet this is always the problem.

 

Still time for some modifications to the pattern but none of them have shown more than a mid-latitude high gradually tilting se.

We should still get the cold though by virtue of the sharpening Euro trough which will send the polar air down towards the UK.

Edited November 14, 2013 by phil nw.

[Frosty.]

GEM 00z is a peach of a run, trough pushing southeast into scandinavia and sliding further south, atlantic high pressure building north and then northeastwards to the north of the uk with a nw'ly veering n'ly and then ne'ly drawing very cold roar winds down across the uk next week, increasingly cold with wintry showers and showers turning to snow, especially on hills and widespread frosts...classic stuff.

[Snowmadsam]

I don't know about anyone else but I'm concentrating on one thing at a time. I'm personally more interested in next week mainly cause it could deliver some quite heavy snow showers along the western side on the UK ( November 2005 repeat?!). At this range we never know how much precipitation is likely till we get a bit closer.

 

Honestly, don't panic folks! Theres still another three months to go until the end of winter! 

 

Lets just go with the flow  

[MR EXTREMES]

Prozac time as Phil suggested and Nick the energy and polar jet it's always been the case eye candy is slowly recedes.

So was the gfs worth the cat litter tray I think not if anything it's looking likely to be a blend of gfs but I do believe the sustained cold spell will soon be a distant memory.

Although cold snap likely then a return back to average daytime temps frost and fog being the biggest feature.

Never was any of the eye candy with in the realistic timeframe so no one for certain can call which will be Top model and be correct although I'd like to say this morning the ecm has decided to drop ideas so it could well be that the ecm was the over progressive model.

[Frosty.]

 

 

Lets just go with the flow

Yep let's just go with the polar maritime followed by arctic flow, sounds good to me.

Edited November 14, 2013 by Frosty.

[bryan629]

good runs from the models this morning...dare i say a bit of a wobble with the ECM ,

 

Joe B seems to think a blocking pattern may well persist .... lets hope so !!

 

Western Europe/Much of US share in cold next 16 days..block may lock after, leading to cold December both also pic.twitter.com/UOtLDNh6kd

 

 

 

 

 

 

[Snowmadsam]

Yep let's just go with the polar maritime followed by arctic flow, sounds good to me.

 

Oh frosty you tease!!! haha!!

 

I'm just wondering if the 6z will get more on board now....today is going to be interesting....

[Frank Trough]

Well that low which develops in the western Atlantic is now going to start causing a real headache, worst still their effects are probably the worst things to be handled by the models. Either way the ECM does not deliver what many want, unless it is a prolonged period of dry weather with widespread frost and fog.

 

absolutely - i think the ECM would deliver some beautiful crisp, frosty mornings. Exactly what i like in autumn:

 

 

 

I'm just pleased to see things dry out a bit and that annoying wind to clear off for a bit. I'd take the ECM immediately! IMBY it takes something pretty special to deliver properly wintry weather and the output of late has never shown this. This frosty style option is much better, plus a couple of really raw days in the middle of next week if that's what people really like.

 

as for the GFS.....best left alone i think. Let it sort out its problems, get an upgrade and have a word with itself. It's wobbling about at the moment like Ashley Young in the box...

Edited November 14, 2013 by Pharaoh Clutchstraw

[snowmadchrisuk]

The 00z GFS is almost Epic , Plenty of precipitation , Although there may be warm sectors at times in the East... Looks good for the Weston side of the UK especially. But with ECM now throwing up a spanner in the works , it's gonna be along wait until this evening.... On GFS this is now within +144 so in a couple of days we should start to be able to put a little more detail on events , but one thing is for sure if GFS is correct , it looks a very unstable flow and Showers should be a plenty, mixed with Cold air and you can sometimes get some quite dramatic weather .

[legritter]

Morning all ,very interesting modells yet again ,i will be back later .putting this computer in attick for retirement ,new windows 8 in box ,a bit sad as its my first and introduced me to NET WEATHER .THE BEST SITE ON THE INTERNET ,will catch you all up ,i hope for tonights epic[ we hope ]modell runs ,cheers everyone . 

[SomeLikeItHot]

The ECM ensemble mean still has high pressure to our west and north west , with the low to the SE. Obviously the ECM op is one option at that range, but a majority of ensemble  members stil seem to be keeping in north of the UK. Personally I think you'be got to expect models at 168 + to give some variety of output run to run. The GFS ensemble mean at the same time (below) seems to agree. Generally this is a pretty good and strong signal at that range if you wat cold weather.

 

Edited November 14, 2013 by SomeLikeItHot

[BLAST FROM THE PAST]

As IB has alluded to seeing low heights over Europe will be and is key, something I highlighted to follow last week.  It is a very useful ingredient because if it gets a tad messy a la ECM a follow up shot is perfectly reason able as it props up HP and also acts like a magnet to further LPs moving in enhancing reload chances.

ECM has watered down, UKMO solid but only goes to t144, GFS flipped to how 12z ECM was, GEM is incredible for cold setup.  So lets see what 12 ECM does from here.

 

As we enter last week of Nov have a little 'warm period' whereby we could have some interesting LP action.  I have to say this pattern approaching I did not expect at all, after the initial plunge the whole synoptics are good 1000+ miles further N and W than I thought.  Hence cold rather than mild.  My CET guess is trashed.........lovely

 

BFTP

Edited November 14, 2013 by BLAST FROM THE PAST

[shedhead]

Well the colder spell now looks pretty much nailed on for early next week, but the overnight model runs have begun to highlight the problems in maintaining the cold once it's become established. Once again GFS has come in for some real stick, but this mornings ECM just goes to show it's perpensity to put more energy into the northern jet arm isn't always as flawed as some would lead us to believe.  Still plenty of water to flow under the bridge yet before we can have any confidence in the evolution beyond this time next week, but if nothing else the last 3rd of Nov holds the kind of promise/potential few if any thought likely at the start of the month.

Edited November 14, 2013 by shedhead

[Summer Sun]

Latest from Gibby

 

All models are agreed that the weather between now and early next week will be changeable with average temperatures in winds between West and North. Today sees a rather chilly NW flow with sunny spells and scattered showers, these chiefly over the North and East and early in the day. A ridge crosses the UK tonight killing off any remaining showers and clear skies will result in a patchy frost. Milder air will be crossing the Northern periphery of a High pressure area to the SW and Friday and Saturday will become rather cloudy and benign as a result. By Sunday a front moving slowly down from the North will bring patchy rain through the day with Monday seeing another one. However, this second one on Monday will usher in much colder air behind it with winds swing Northerly with sunshine and showers developing with some snowfall on hills in the North and more widespread frost than of late overnight and inland.

 

GFS then intensifies the cold next week as winds veer NE in response to a pressure build to the NW. The result will be a North/South split developing with the North seeing very cold and frosty weather under clear skies while Southern areas close to Low pressure over NW Europe stay cloudy and cold with rain or sleet at times and snow over the hills. The pattern remains similar for the rest of the run with Southern areas likely to continue to see very unsettled and rather cold weather with rain at times while the North see the best of any drier spells. Late in the run drier weather is shown to extend to many areas as High pressure settles over Northern and Eastern Britain.

 

UKMO today closes it's run with a showery and chilly NW airflow on Tuesday veering to an even colder NE'ly on Wednesday. A mix of sunshine and showers are likely especially near Western and later Eastern coasts and these could be wintry on the hills generally and perhaps to lower elevations for a time in the North. The NW shows signs of settling down soon after the term of the run.

 

GEM today shows a North/South split developing next week. The early days will see northerly winds and wintry showers giving way to cloudier skies across the South with rain or sleet at times while the North tuns steadily more settled but with frost and fog problems becoming widespread with time.

 

NAVGEM shows a North then NE flow next week too with some rain, sleet or wet snow over the hills of the South while Northern regions slowly become less settled as High pressure tries to build in from off the Atlantic. It would be generally cold over all areas through the week.

 

ECM today quickly removes a cold North then NE flow away from the UK as we move through next week quickly shifting the emphasis away from wintry showers into one of cold and quiet weather with widespread frost and fog problems as the week moves on and into next weekend.

 

The GFS Ensembles show a much tighter pack this morning well supportive of a colder spell next week before the trend to lessen it's grip over the UK is shown though never becoming mild. Rain at times is as usual shown scattered through the run today and some of this will no doubt fall as snow at times over higher ground, especially in the North. The operational run was a warmer outlier in it's later stages.

 

The Jet Stream is show to be ridging High over the Atlantic and across Iceland at the moment. Through the coming days this sinks steadily South on it's current trajectory before turning directly North to South over the UK early next week to eventually set up a much more Southerly position in a week or so time.

 

In Summary today a colder spell is still looking very much on the cards. The general theme appears to be a few days of Northerly winds with wintry showers to be followed by a swing of winds to the NE as pressure builds to the NW of the UK. This would change the distribution of precipitation towards the South and East while Northern and Western areas become dry, cold and possibly frosty and foggy. However, through my years of experience ECM this morning has come up with the most likely prognosis that I think will more likely happen as High pressure builds across the UK following the Northerly and bring a nationwide cold and foggy period, something I hinted at last night. having said that the majority of output this morning does not show this so the colder and more wintry solutions do hold some credibility currently.

 

The one word of caution I would use though for those salivating over these wintry synoptics is not to expect too much especially if you live on low ground and in the South. Sea surface temperatures are still relatively high and we are surrounded by them. As a result any precipitation that occurs is likely to be of the watery variety despite cold enough uppers for snow (see link below). The air at sea level will warm surface air sufficiently for this and also given that we are still only in mid November we could of done with these synoptics in January and February rather than now as I feel there is a good chance that they could be wasted on delivering rain and sleet rather than what many want.

 

http://www.thebeachguide.co.uk/sea-temperature

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm