Winter Model Discussion - 12/01/13 06z Onwards

[IDO]

Have u looked at surface temps and sypnotics ?

The temps still cold but never have much faith in those figures.

[Continental Climate]

They are not bad at all!

at day 5 the mean is around -7 and the cluster is tightly grouped compared to of late.

Thats what i thought i looked at them and saw a nice clustering until the 18th which is still fi Im quite happy with the ensembles, some people like to cause unnecessary worry i think

Edited January 12, 2013 by Continental Climate

[Dean E]

Well I am very confused now, having just watched the BBC Forecast for Monday, it seems Monday that we have 2 separate ''rain / snow'' bands passing down the country , the first is likely to be more of a snow event, the second and the one that they are ''watching'' appears (at least going by the BBC graphics) to be mostly rain in the SE Corner (London included), but snow across E Anglia / Lincs , which falls in line pretty well with Netweathers own PPN type chart for the same period.

you can see the first band here running down the spine of the country ,(mostly all snow)...the main band is following behind it

here's the PPN charts for Monday evening

and the PPN Type charts for the same period

It's a close call, and my heart would love to see this all falling as snow, (if would be after dark and there will be snow preceding it)....time will tell, but I have a really bad feeling that those South of London.. Southern and Western.Kent / Eastern East Sussex / West Sussex / Southern and Western Surrey might get more of a mix of rain / sleet / wet snow as opposed to proper snow, a bit of IMBY-ardism I know but that's how I see things panning out for the SE Quadrant of the UK.

Folkstone and the extreme SE Tip look set for a real dumping as do more central areas on Monday.....AS THINGS STAND !!!

That was in the Low Res on BBC Weather graphics, always well under estimated. Mondays event was a wash out for areas South of the Midlands, then once the Hi res came in, changed over to snow for most.

Take the BBC graphics with a pinch of salt, any further than a day out.

SM

[The Giant Daddy Jackpot]

Very good potential for heavy snow showers across the SE on Wednesday with some perhaps merging together for more prolonged snowfall. Essex, Kent and East Sussex in the firing line.

[full_frontal_occlusion]

Some folks are getting hung up on the 'ppn type' charts which ALWAYS show the fringes of the snow transiting from rain to snow.

Don't get hung up on this, it is purely a graphical representation and does not depict what is likely to happen on those fringes.

The METO weather warnings quote 'An area of rain, sleet and hill snow spreading into northwestern Scotland by early Monday is expected to turn increasingly to snow to low levels as it moves southeastwards through the day.'

The keywords are: turning increasingly to snow to low levels as it moves southeastwards.

As the sinking low moves south, the ppn will pivot around the low. Expect the SE will see more snow as the LP track favours those areas. Kent, East Sussex, Essex, Suffolk, London, Herts could all get a pasting.

ffO.

[IDO]

ECM mean at 144 (0z rather than the others at 06z): GFS mean:

The GFS op:

Cannot use the ECM op as it was a mild outlier. The GFS and ECM means are similar, compared to the GFS op (that sustains the pattern much further west). The means hinting at similar set ups.

Edited January 12, 2013 by i'm dreaming of...

[bluearmy]

The temps still cold but never have much faith in those figures.

You should cos we live on the ground, not at 850 hpa !!!

[Frosty.]

There is a lot to admire about the Gfs 06z op run, the way the cold block fights off the atlantic is really impressive and the cold weather survives mostly intact until very near the end. It looks as though there is a battle ahead with the cold block being up for the challenge of keeping the uk locked in a cold and wintry spell for the next few weeks. It looks like a lot of snow will fall during monday and then snow showers for eastern areas.

[bradymk]

just want to compare some long term developments. JMA and CFS anomalies up to week 4 show surprisingly relatively good agreement with the pattern. Not saying they are correct but they both go for the same pattern at the moment.

JMA here has +ve heights western greeland and the iceland area for this week. For days 9-15 it still shows the +VE over Greenland and Iceland with also a strong signal for low pressure over southern Europe with a strong North Easterly flow and low pressure running to the south of us. Week 3 and 4 shows the main heights moving slightly westwards with low pressure over europe still but further north with slightly milder weather for the southern half of the UK but northern parts of the UK still cold. Temperatures still below average but not as cold as week 1 and 2 but that is a long way out.

Now the CFS V2 has been consistent with this cold spell along with many other anomaly charts. This for week 1 shows +ve heights to our north, low heights to our south with an easterly flow. Week 2 shows strong +ve heights over Greenland and Iceland again with low heights to our east and south with a north easterly flow. Week 3 shows a similar pattern but with heights to our north moving westwards slighty into Eastern Canada with low heights still to our south and east although low heights further north into the southern half of the UK so staying cool but not as cold. Week 4 showing similar to week 3.

Now im not saying these are right but thats pretty good consistency from CFS and JMA anomaly charts for each week and both show a similar pattern with a easterly this week, north easterly next week before heights move more west based causing temperatures to rise but still below average.

Please dont go away thinking that +ve heights means a Greenland High because +ve anomalies for Greenland just means higher than normal and normal is pretty low for there during the winter. All they are is a deviation away from the mean. Also, I am not sure these are correct myself as I think the first week of February maybe colder than these suggest but i thought it was interesting how similar both long range models are at the moment. Both are cold into February with below/well below temps.

Edited January 12, 2013 by bradythemole

[Summer Sun]

06z ensembles

[weatherguy]

Yes the op is a cold outlier from mid-week and most members trend to the ECM milder scenario:

short GEFS:

I don't see it like that, the op is in a very strong cold cluster which are the majority of members, while there are just a couple of extreme outliers at the milder end.

(until the very end of mid week, which is of course FI...look at the scatter past the 17th/18th)

Edited January 12, 2013 by weatherguy

[Buzz]

There is a lot to admire about the Gfs 06z op run, the way the cold block fights off the atlantic is really impressive and the cold weather survives mostly intact until very near the end. It looks as though there is a battle ahead with the cold block being up for the challenge of keeping the uk locked in a cold and wintry spell for the next few weeks. It looks like a lot of snow will fall during monday and then snow showers for eastern areas.

Quite. I do wish that certain parties (no names mentioned) would stop picking holes and looking for the breakdown, then backing up their arguments with charts six days ahead (especially given that FI is about 72 at the moment).

Regarding the ECM and 'vaguely similar but not really' 06 GFS - in a day or two the models will probably pick up on another signal and run with it; it's too far ahead to take too much notice of. Not saying it won't happen that way of course and the ECM does have a good track record at 5 days out, BUT things are different right now with the modelling problems associated with the SSW. I hate to resort to the tired old phrase 'the models are struggling', but this time it applies in spades.

[The PIT]

Just a few points:

The ECM is the model that verifies best in the day 5 range. Therefore, it's version for later next week is a worry; however it is a little by itself so I am not going to draw too many conclusions.

The fact is the models all show very different scenarios, even the ones that stay cold, therefore they are all likely to be wrong and there will prob be a blend of solutions.

Any how, people should focus on the here and now with monday looking like a snowy day for much of the uk. Also The eye in the sky is correct in saying the snow has not even reached the time frame where it would have reached the south east on the nae.

Not every single time though over the year it may come to tops but they're times when it's second and even third best.

The gfs 06 oz continues the 00 oz theme which is pretty good. ECM seems to be a mild outlier thankfully and hopefully it'll drift back to a cold outlook.

[Methuselah]

I personally feel that the 06z can only really be used for trending and giving some idea as to how the next run will unfold.

With its missing balloon data, its obviously not the full bag of spanners, but its certainly handy to get some "idea" of what the next runs can be like.

I always take the 06 with a pinch of salt. If it manages to get to grips and output similar to other models that evidently there is a strong signal hidden in the data somewhere.

Tbh mate, I tend to take them all with a pinch of salt. Especially at times such as these, when all the signals appear to be far more mixed than usual...FI's hardly more than T+72?

[kev238]

Of course the ECM can sometimes be the second or third model at times, much like man utd can be beaten at times, however averaged over a long period of time it is the top model, and most people on here will state that and were stating it when we had the issue of the shortwave and where it was going to go.

My major point is that if the big three are not singing from the same sheet then don't discount anything. Surely that is fair enough?

[Frosty.]

Tbh mate, I tend to take them all with a pinch of salt. Especially at times such as these, when all the signals appear to be far more mixed than usual...FI's hardly more than T+72?

I am hoping so much for a memorable cold spell rather than just another run of the mill cold snap, winter has been rubbish so far and so much now rests on the latest met office update, hopefully they can make some sense of the mixed signals you mention.

[Met4Cast]

Of course the ECM can sometimes be the second or third model at times, much like man utd can be beaten at times, however averaged over a long period of time it is the top model, and most people on here will state that and were stating it when we had the issue of the shortwave and where it was going to go.

My major point is that if the big three are not singing from the same sheet then don't discount anything. Surely that is fair enough?

Whilst I agree the ECM is one of the, if not the top model, when it's showing a massive outlier which is completely against nearly all of it's own ensemble members not to mention the background signals, it's probably not worth giving it a whole lot of attention.

[stainesbloke]

Of course the ECM can sometimes be the second or third model at times, much like man utd can be beaten at times, however averaged over a long period of time it is the top model, and most people on here will state that and were stating it when we had the issue of the shortwave and where it was going to go.

My major point is that if the big three are not singing from the same sheet then don't discount anything. Surely that is fair enough?

Yes quite right IMHO. However the majority of models have been going for cold/blocked with one or two (be it ECM or GFS) throwing out other solutions before changing back. The outlook therefore is weighted towards cold/blocked but of course nothing is certain. A lot of cold bias goes on here which makes people scorn any model showing mild solutions, be it the model they were touting as infallible a few hours before....makes me laugh

[weather eater]

Quite. I do wish that certain parties (no names mentioned) would stop picking holes and looking for the breakdown, then backing up their arguments with charts six days ahead (especially given that FI is about 72 at the moment).

Regarding the ECM and 'vaguely similar but not really' 06 GFS - in a day or two the models will probably pick up on another signal and run with it; it's too far ahead to take too much notice of. Not saying it won't happen that way of course and the ECM does have a good track record at 5 days out, BUT things are different right now with the modelling problems associated with the SSW. I hate to resort to the tired old phrase 'the models are struggling', but this time it applies in spades.

That is certainly the view of both the MO and the NOAA, we have already seen several possible trends appear only to disappear again over the past few days, longer if we go back to the two big easterly runs the ECM produced about a week ago, another run of raging easterly’s by both the ECM and GFS, but at different times, the long run, six I think, of the GFS determined that Mondays snow event would not happen, the shortwave moving east and the Azores high toppling in, but I guess this being the model thread people will discuss the models and try to get a handle on the way ahead, hoping that the models are finally getting a grip, personally I’m pretty sure they haven’t.

[Frosty.]

Whilst I agree the ECM is one of the, if not the top model, when it's showing a massive outlier which is completely against nearly all of it's own ensemble members not to mention the background signals, it's probably not worth giving it a whole lot of attention.

we will very shortly find out whether it is a massive outlier, any minute now actually..holds breath for latest met office update Edited January 12, 2013 by Frosty039

[Captain Shortwave]

There has been one clear trend over the last few days, and that is the continuous downgrading of the strength of the jet coming out of the Eastern seaboard across the atlantic. Look at the link up behind mon/tues shortwave. That was not even possible a few days back due to energy piling through the gap with high pressure to the north. ECM/GFS are cottoning on to a final solution, but I feel UKMO and GEM has shown far greater consistancy and with the mets bullish forecast suggests perhaps a stronger scandi high forming. I would think that would be the final outcome.

[IDO]

Of course the ECM can sometimes be the second or third model at times, much like man utd can be beaten at times, however averaged over a long period of time it is the top model, and most people on here will state that and were stating it when we had the issue of the shortwave and where it was going to go.

My major point is that if the big three are not singing from the same sheet then don't discount anything. Surely that is fair enough?

Fair.

After the short wave fiasco from GFS and their poor continuity of Op runs over the last few days I would favour the ECM. The op has to be discounted as it is too progressive but the mean is solid with a slow incursion of the Atlantic; not dissimilar to the GEFS mean. Both suggest a snowy start to next week, with cold for the next 5-7 days, accentuated by any lying snow. What happens next weekend onwards, with the SSW likely to be more influential, who knows?

Obviously we all would prefer either of the GFS 00z or 06z op's as they increase the risk of further snow, whereas the means suggest HP/ridging close to the UK so more settled. But the latter has little support, including the control.

Overall excellent for cold.

MOGREPS Update: About half of the MOGREPS ensembles show a big Atlantic slider low for next Friday, could be a lot of snow if that came off. Additionally, very good ensembles in the longer term, most have HP over Scandinavia or Iceland, two have a UK high.

(source: post 364 http://www.theweatheroutlook.com/twocommunity/yaf_postst9498p18_Model-Output-11-1-13-21-15.aspx)

[Frosty.]

Great news for coldies, latest meto goes for continued cold with severe frosts and more snow, although there is uncertainty from thursday onwards, on balance, a cold solution is favoured..i'm happier now.

[The Eagle]

When you look at the GFS control run, the ECM and ens the most likely outcome appears to be the ECM op.

http://www.meteociel...&carte=0&mode=0

Edited January 12, 2013 by The Eagle

[raul_sbd]

hi could someone post the link to the met office text prediction?