Model Output Discussion

[MP-R]

Great post Polar Continental, thanks!

Where today's low is in a rather unfavourable place for the south of England and it favouring snow for further north, Monday's low at the moment is better situated for those in the south hoping for some white stuff but maybe less so for the north. Certainly, some fantastic model charts though:

http://www.wetterzentrale.de/pics/Rtavn961.html

[snowray]

Has the 06z picked up on the upstream paterns that certain members have been refering to somewhat insistently I wonder? Without wishing to stick my kneck out too far, I would suggest that the 00z would be a snowfest for many a' la, dare I say it Robert.

Uppers are never all that low, but none the less I kept thinking to myself that I remember this sort of patern from a memorable Winter period of the distant past, and came up with this chart for 11th Dec 1981.

Spot the difference.

Be interesting to see how things pan out, one chart being for early Winter and the other for late Winter of course.

Edited February 18, 2010 by snowray

[TEITS]

Latest NAE chart.

http://expert.weatheronline.co.uk/daten/proficharts/en/nae/2010/02/18/basis06/ukuk/prty/10021818_1806.gif

Possible snow event Saturday.

http://www.wetterzentrale.de/pics/Rmgfs543.gif

Gosh so much going on!!

Make that Sunday aswell. :lol:

http://www.wetterzentrale.de/pics/Rtavn784.png

Edited February 18, 2010 by THE EYE IN THE SKY

[Ben_Cambs]

Latest NAE chart.

http://expert.weathe...021818_1806.gif

Possible snow event Saturday.

http://www.wetterzen...cs/Rmgfs543.gif

Gosh so much going on!!

Make that Sunday aswell. :lol:

http://www.wetterzen...cs/Rtavn784.png

Thanks mate, there is a lot going on and we could have potentially 2 more snow events in the next 4 days! Hopefully now a trend from the GFS as shown in the 18z and 00z for a cold outlook, I must admit this is the most interesting model watching Ive ever seen! (In about 4 months of model watching ) Surely if this continues the GEFS ensembles will gradually agree more with the OP run?

[Geordiesnow]

Really interesting period of weather coming up as far as cold lovers and snow fans are concerned, certainly the risk of some prolonged snow events on this mornings runs. PPN charts will as ever still change so be wary when looking at these but some places could see some dumpings.

As ever in these situations its watching the radar, as i found out this morning. Expected a dusting just going by the forecasts but at the moment, i got a right good old covering of snow here although it would seem very localised but it shows that at the end of the day, mother nature will decide what happens.

I think the trend for something milder is getting stronger now with the UKMO/ECM starting to agree on this but it still a little too far out to be sure. I do think at this stage that any mild weather will not be excessively mild but more like average temperatures so i doubt we will see widespread double figures anytime soon. However as we can see, its not that plain simple and the cold could carry on until the end of the month but i think the is an outsider bet at the moment.

[kev238]

I have to say that the 6z is perhaps the most snowy run (for the Midlands/ Northern Ehgland) I have seen in the high resolution part of the run. I dont think it can really pan out this way but it is good to see! At least the possibilities are there and are within the 'reliable' part of the run!

[Tom D]

I have to say that the 6z is perhaps the most snowy run (for the Midlands/ Northern Ehgland) I have seen in the high resolution part of the run. I dont think it can really pan out this way but it is good to see! At least the possibilities are there and are within the 'reliable' part of the run!

Indeed, before t+180 I counted 6 possible snow events (including today) for Wales, the Midlands and northwards. I would say caution however is needed after t+120 as there's some important differences between the 06z and the 00z even at this stage.

[Frank Trough]

hmmm. Lots of excitement for the midlands northwards. However, down here in south Hampshire to me it looks like being cold, wet and thoroughly miserable. I didn't see the 12z's yesterday (or GFS 18z) but the "event" for monday that was being shown (which may have given some interest here) seems to have been shunted further southeast into the low countries?

[snowray]

hmmm. Lots of excitement for the midlands northwards. However, down here in south Hampshire to me it looks like being cold, wet and thoroughly miserable. I didn't see the 12z's yesterday (or GFS 18z) but the "event" for monday that was being shown (which may have given some interest here) seems to have been shunted further southeast into the low countries?

Yes small but major differences when comparing 00z with 06z. Much milder in the South, Snow bonanza Mildlands and parts of the North, very cold in Scotland. So if you were driving up the M1, it would start as heavy rain, then a transition to sleet around Northampton, and within a couple of miles it would seem as if you had been transported to Siberia with lots of snow and probably blizzards!

Of course a few miles here and there with these synoptics, as little as 20 or 30 miles, less even, are going to make a hell of a difference to the conditions your likely to see on the ground. The colder air my stick further South like the 00z was showing, or shift a bit further North. Idealy we want things to stay a bit further South to prevent things becoming too marginal for even the Midlands. Lots and lots of potention though guys and girls!

Edited February 18, 2010 by snowray

[conor123]

Incredible run the 06z if you like snow for the majority of the UK, in fact parts of Wales & The Midlands would end up with the most snow more many years if it came off.

[Guest North Sea Snow Convection]

Cold and unsettled continues to be the theme for the short to medium term and certainly the very marginal but still wintry potential looks more widespread than a few days ago as the colder air and low pressure areas are further south over a greater part of the UK than previously indicated.

Further afield, the models continue to suggest a repeat of the west based -NAO pattern progression of a couple of weeks ago and trying to push atlantic air in from the south west. Deja vu really. At the same time very cold air remains to the north east and the only thing stopping pressure rising south westwards is the troughing extending between the Uk and into the Baltic all linking up and phasing with the very southerly tracking jet stream.

As far as the atlantic part of the equation is concerned, as I have just read from a posting last night and would agree, there is no real fundamental support for mild south westerlies to spread across the Uk and it does appear to be an FI default signal, continually correcting back again, as the modelling gets into a closer time period. The models over exaggerate downstream ridging from Iberia and the extent of low pressure moving SW-NE , only to correct both the movement and the orientation of the lows later as well as flatten the ridge back, much as Dave, TEITS, said earlier. With further negative zonal winds to affect the lower tropopause in the pipeline, and the very surpressed jet stream remaining then the current stand off is unsustainable as I see it and there remains every chance of the colder drier upper air to the north and north east eventually winning the struggle. That said, it stays pretty cold in the meantime anyway of course!

[nick sussex]

Morning all

Overall I think today we see a continuation of the suppressed lows as these get within 120hrs, the models seem to be over estimating how far north these get.

Output of the day IMO from a wintry perspective is the UKMO.

http://www.meteociel.fr/modeles/ukmo2.php?nh=0&ech=96&carte=1021

Here we see the low approaching from the SW with that small ridge out of the Low Countries, that looks very favourable for snow as the low tries to move in at 120 hrs.

http://www.meteociel.fr/modeles/ukmo2.php?nh=0&ech=120&carte=1021

Again though theres so much variance between runs so just a longshot at present.

Regardless of what the later output shows the trend really should be for heights to build to the north as we head into the turn of the month with the west based negative NAO transferring eastwards, the west USA ridge looks to be breaking down with segments of the PV dropping south, the models however seem to be very unsure of where these will set up.

We should expect to see some very volatile model output because of this although the final destination IMO will be a cold turn of the month into the start of March.

Earlier of course some interest today with that low heading ene especially for the Midlands eastwards. A possible snow event into the start of next week if the UKMO verifies, here though a big if! As with all the output hard to look with too much confidence in terms of the local detail more than 48hrs ahead.

[Guest North Sea Snow Convection]

We should expect to see some very volatile model output because of this although the final destination IMO will be a cold turn of the month into the start of March.

Hi Nick,

Yes I very much agree, and why I stated 'deja vu' in my own mumblings just now. By that, referring to something akin to the massive swings in outcomes from model output that we saw leading up to the mini easterly of last week.

Every reason to expect something similar I think.

[nick sussex]

Hi Nick,

Yes I very much agree, and why I stated 'deja vu' in my own mumblings just now. By that, referring to something akin to the massive swings in outcomes from model output that we saw leading up to the mini easterly of last week.

Every reason to expect something similar I think.

Morning Tamara yes I agree with your earlier post, like you I expect the colder air to the ne to win out eventually,but not before the end of the month as the pattern has to play itself out.

In the meantime quite alot of interest with a few possible snow events so not bad at all.

[Eugene]

Another GFS run with a ton of potential and any mild pushed back again compared to yesterdays runs , i sense some heavy snow for the midlands and north next week, just something about the setup for next week at the moment that supports a snowfest for some and a rainfest for the extreme southerners

I wouldn't mind a day or two of proper mild weather(+10C) to be honest, it is frankly getting very weird now not experiencing any TM airmasss at all, back to cold not long afterwards once the novelty has worn off

[D KARLSON]

Really interesting period of weather coming up as far as cold lovers and snow fans are concerned, certainly the risk of some prolonged snow events on this mornings runs. PPN charts will as ever still change so be wary when looking at these but some places could see some dumpings.

As ever in these situations its watching the radar, as i found out this morning. Expected a dusting just going by the forecasts but at the moment, i got a right good old covering of snow here although it would seem very localised but it shows that at the end of the day, mother nature will decide what happens.

I think the trend for something milder is getting stronger now with the UKMO/ECM starting to agree on this but it still a little too far out to be sure. I do think at this stage that any mild weather will not be excessively mild but more like average temperatures so i doubt we will see widespread double figures anytime soon. However as we can see, its not that plain simple and the cold could carry on until the end of the month but i think the is an outsider bet at the moment.

No snow at all here in N Yorks save for hills ,having looked at the charts this morning i noticed the low to the east is now very close to the east coast and this looks like a player as we go into the weekend ,there is even a chance of some colder air filering in for a time.

[Tucco]

Well if 06z verify's it looks like the dry boring weather of the last month or so here will continue here. All the action is further South which has been so often the case this winter. Real lack of snow from frontal systems here. Could do with everything moving North 100 miles. Hopefully my luck will change.

[kold weather]

Well thats an insane run for the Midlands, 5-6 snow events in the space of 7-8 days on this run, very USA like with the storm tracks just constantly feeding through on a similar track as the last one.

Needless to say though the ensembles are a total mess with what to do with the low and therefore many many different solutions, most have at least 2 snow events for the Midlands however quite a few even give heavy snow for the south as well...wonder if this pattern will be close to Feb 78....

[mushymanrob]

Folks the thing is your all talking about will it wont it break down but , but before we even get to TUE we have a wk of -5 uppers under low pressure and increasingly cold toward the wkend so with so much interest in the short term im not even thinking about the breakdown cause when its mild all we do is moan in the winter about it been mild and looking out for trends towards colder weather .

Seems to me ppl are that obsessed in fi they are missing good winter weather out there window.

its GOING to break down, and not before time either, and those of us who dont like this dreary, drab, cold weather will have to look to fi for a change. i dont call damp, dull, raw cold 'good weather', unless you are inside of course!

the 06z again promises milder weather into next week... yep some volotile weather looks set as the mild/cold battle commences. as for snow events.... i cant see it snowing here today dispite the tv's graphics telling me it WILL. its far too mild (as in well above freezing, not really mild though, relatively).

so what if it snows? its not going to settle and will rapidly melt ... in my book if it doesnt settle it may as well rain.

Edited February 18, 2010 by mushymanrob

[BarnetBlizzard]

Well if 06z verify's it looks like the dry boring weather of the last month or so here will continue here. All the action is further South which has been so often the case this winter. Real lack of snow from frontal systems here. Could do with everything moving North 100 miles. Hopefully my luck will change.

Yh, well i could do with it moving 100 miles south . Looks like the midlands and northern England are best placed for this coming week, although there will be snow in other places aswell, it will be shortlived. Im just glad theres some intresting weather coming up instead of this boring weather we have had.

[carnun]

its GOING to break down, and not before time either, and those of us who dont like this dreary, drab, cold weather will have to look to fi for a change. i dont call damp, dull, raw cold 'good weather', unless you are inside of course!

the 06z again promises milder weather into next week... yep some volotile weather looks set as the mild/cold battle commences. as for snow events.... i cant see it snowing here today dispite the tv's graphics telling me it WILL. its far too mild (as in well above freezing, not really mild though, relatively).

so what if it snows? its not going to settle and will rapidly melt ... in my book if it doesnt settle it may as well rain.

If the charts for the next few days verify there will be heavy snow in parts of England and it will stick. I suspect we'll (Ireland) miss out as usual with the lows going further south than anticipated.

Edited February 18, 2010 by carnun

[TEITS]

Yh, well i could do with it moving 100 miles south . Looks like the midlands and northern England are best placed for this coming week, although there will be snow in other places aswell, it will be shortlived. Im just glad theres some intresting weather coming up instead of this boring weather we have had.

I actually feel rather sorry for those in N England because IMO the track of these disturbances look to affect S England rather than N England. At the moment based on all the model output I would say the N limit is around Derbyshire, maybe just getting into S Yorks.

Back to the medium range and I fully agree with Nick S, Tamara. Just watch over the next few days how the models will back away from the mild SW,lys. More of the same for me i.e snow events for S England?Midlands/Wales and if anything the risk of it turning even colder than we have now.

[SP1986]

Sorry Stephen, but you have repeatedly posted this during the winter and you have failed to give evidence to prove it. The GFS today OVERstated temperatures by a few degrees here, so it works both ways.

I have been going on about this yes, due to a number of people suggesting that it would happen on the scale that it did a few months ago, there's no need for me to post evidence if you're the one who doesn't believe then perhaps you should go out there and try to disprove it.

Besides a little reading and some common sense doesn't go amiss.

Firstly I stated that low temperature of the order in terms of widespread and severity are unlikely, I think that's a fair point, I never said they wouldn't occur locally. The really low temperature back in December were underdone by the GFS. The point if anything is the 2m temperature predictions are usually wrong and useless on some occassions. It is best working out the temperature from the 850's to get a widespread common value (give or take extreme localised values in rural areas)

Second of all I put that on most occassions it was doing this, not all of the time.

[mickpips]

I actually feel rather sorry for those in N England because IMO the track of these disturbances look to affect S England rather than N England. At the moment based on all the model output I would say the N limit is around Derbyshire, maybe just getting into S Yorks.

Back to the medium range and I fully agree with Nick S, Tamara. Just watch over the next few days how the models will back away from the mild SW,lys. More of the same for me i.e snow events for S England?Midlands/Wales and if anything the risk of it turning even colder than we have now.

Dont feel too sorry for us TEITS , after all I have had one of the snowiest winters in my memory this winter , with lying snow for well over 20 days and touching 11 inch at one point in North Leeds. Even yesterday we had snow into the evening giving a light covering when most models just forecast the band to peter out into South Yorkshire.

Anyone will tell you how difficult it is to forecast not only the type of PPN but the extent and track of any over the next 5-6 days ... I see the Met have an early warning out for next monday already !! Must be some confidence already ?!

[bluearmy]

i have a feeling, looking at the 00z's, that the flow will become more supressed over the next week or so and with it the likelhood that the disturbances may well run across the near continent and there is a good chance that the northern part of the UK may well pick up a frigid noreaster by the end of next week. this leaves most of the UK in a cold no mans land under an elongated trough with any precip difficult to pinpoint at moe than T24/T36.