Model Output Discussion

[Secret Society]

It's their way of backtracking...nice and gently and hope no-one notices! Expect the words cold or rather cold to disappear in the next day or two if the model output continues to trend in the way it has been for the last day or so.

that doesnt sound very professional.

why would they do that?

yet you were saying they are best?

writing lies is not their business.

[Frosty.]

Unfortunately the UKMO is verifying well at the moment so unfortunately we can't clutch this straw, it will be interesting to see how much of a dive the GFS takes later on with its verifications stats looking to implode into laughing stock territory!

Do you know I blame myself here for not sticking to my thoughts about the GFS and easterlies and also for not taking more note of the UKMO, its notorious for refusing to go with easterlies and being proved right so certainly i won't be making that mistake again.

Regarding the UKMO further outlook that expects the trough to make it far enough eastwards so because of this we want rid of the block to the east as soon as possible as pressure is likely to remain high over Greenland, to be honest I've had enough of Siberian blocks, the sooner its gone IMO the better.That will allow colder air in and reduce the mild mush!

It's only a week ago the ukmo model was showing a strong Easterly taking over the country with deep blues rushing west, that soon changed with a light E'ly but it was still cold so the ukmo bbc forecast this lunchtime is being very bullish about mild air taking full control by friday but there could still be some problems with that if there are any errors it might change but now i'm straw clutching.

[PB22]

that doesnt sound very professional.

why would they do that?

yet you were saying they are best?

writing lies is not their business.

I was joking! Crumbs people are tetchy today. I shall go and insert a smiley, sorry!

[aspire27]

From a newbie point of view this thread is becoming so hard to follow with regard to the model output. I remember a couple of days it was all about the

beast from the east now its all mild mild mild.

Makes me think some people need to calm down a bit. I bet we get a brilliant cold chart in the next few runs...then once again the beast is on!!

[Ian Fergusson]

Interesting Metoffice 6-15 day with them saying becoming Cold to very Cold later. I Imagine they are picking up on the blocking out East and also starting to build over Northern Greenland. I don't think all is lost and the second week in Feb has always been the favourate starting point in my view for the next Cold Spell.

Yes, I've got to say I've seen no sign of any supposed 'back-tracking' from the medium range guys at Exeter in their briefings lately. The messy, mild(ish) set-up into this coming week has been a consistent theme over the past 48hrs of briefings (not least based on the GM) and as I posted yesterday, it's been the 10-15 day period where UKMO has focused any suggestion of a colder easterly returning. I'm awaiting the next detailed briefing notes but this abstract from the 00Z briefing makes the point well enough on behalf of the good folks at Ops Centre:

"4. Trend For Days 10-15: The low level flow is expected to back easterly with colder weather advecting westwards across the UK. Good deal of dry weather in the west, but increasing risk of snow showers for eastern and central areas and low PROB of sleet and snow in the far south later. Widespread frosts.

5. Discussion: There remains considerable uncertainty in the evolution during the coming week, with some models, including JMA, and some EPS members maintaining the block, whilst the main signal from the ensembles is for progression of Atlantic frontal systems into the UK. During the trend period, there remains a good signal for trough disruption over the Atlantic with a much colder easterly flow developing. This latter aspect has moderate confidence."

I do again stress this was a midnight briefing and will shortly be superceded!!!

[MP-R]

From a newbie point of view this thread is becoming so hard to follow with regard to the model output. I remember a couple of days it was all about the

beast from the east now its all mild mild mild.

Makes me think some people need to calm down a bit. I bet we get a brilliant cold chart in the next few runs...then once again the beast is on!!

Agree with this! We'll probably find that after all this talk of woolie hat easterlies and tee-shirt southwesterlies that we'll get somewhere in the middle like lows trying to push in but a strong southeasterly flow like that of 12th-15th Jan. With all that high pressure to the north it can't be a normal breakdown from the Atlantic, not at first anyway.

[nick sussex]

It's only a week ago the ukmo model was showing a strong Easterly taking over the country with deep blues rushing west, that soon changed with a light E'ly but it was still cold so the ukmo bbc forecast this lunchtime is being very bullish about mild air taking full control by friday but there could still be some problems with that if there are any errors it might change but now i'm straw clutching.

I applaud your efforts Frosty! but we're all out of straws! The best that can happen is that UKMO is just a little too progressive and the UK can scrape some snow before that major low moves in. At this point you need to see the block to the east disappear back to Siberia to allow pressure to fall over Scandi, all the models agree on a negative AO and negative NAO although the latter does look a bit too western based. After this we need to see the trough progress eastwards, at that point it may turn colder again, we don't want the block to sink and hang around otherwise thats a recipe for mild sw'erlies.

[karyo]

Because the block to the east is likely to sink you want rid of it as soon as possible, if it hangs around for too long the Atlantic trough won't be able to move east and you'll get stuck in mild sw'erlies, pressure is going to be high to the north and this is now the only route to colder weather, the best we can hope for is perhaps a little snow this week before the major low moves in, after this we want rid of the block to the east.

Theres zero chance of an easterly now so we should just move on and not dwell on what ifs.

I agree but I fear that the block will become stubborn to the east and we get stuck is mild Atlantic flow, as the systems are not able to move east enough to bring some polar maritime air.

Mr Data nailed it earlier by saying that easterlies have been disappointing this winter. Our mighty cold and snowy spells came from the north and that's where we should focus on.

Karyo

[Cheese Rice]

To me the GFS looks like a complete snow fest, everywhere is likely to see snow at some point this week if it came of. Yes near the end of the run mild SW's are predicted but I'm not buying it atm.

[Guest North Sea Snow Convection]

Catching up slowly I see.

I think to be honest this sort of post which characterises the type of slant you keep putting on things is as wrong as the 'I know better it is going to get colder' camp.

Or are you professing to be having more perceptive foresight and wisdom than the METO?

The truth, is no-one actually knows what we are supposed to be 'catching up with' yet. So I think that any 'I told you so's' are a tad premature and are at least as bad as any cold weather back slapping.

That update clearly states the uncertainty of the pattern, and I am sure if it was weighting in favour of short term cold weather, you would select to say the same.

I think in the circumstances it is a well pitched update, and leaves room like any update should for further changes to occur. Much as they may do tomorrow or the next day.

The short term set up looks very much like Jan 1969 to me - and we know how that -AO pattern followed up.....

If this was a switch to a definitive +AO zonal set up I could understand a much more confident progression to a mild set up. But it isn't. It is a highly volatile one that is full of modelling minefields. And if these are taken too lightly they tend to detonate towards 'one'. Shall we say as politely as possible.

Edited January 31, 2010 by North Sea Snow Convection

[SP1986]

Its unreasonable to expect the flick of switch to milder weather when this southwesterly comes in, if mild air keeps coming it's going to be a slow process. I do see hints of mildness being pushed back a bit but it is sufficient even by Friday to stop atmospheric rooted cold air affecting us.

[andymusic]

Yes, I've got to say I've seen no sign of any supposed 'back-tracking' from the medium range guys at Exeter in their briefings lately. The messy, mild(ish) set-up into this coming week has been a consistent theme over the past 48hrs of briefings (not least based on the GM) and as I posted yesterday, it's been the 10-15 day period where UKMO has focused any suggestion of a colder easterly returning. I'm awaiting the next detailed briefing notes but this abstract from the 00Z briefing makes the point well enough on behalf of the good folks at Ops Centre:

"4. Trend For Days 10-15: The low level flow is expected to back easterly with colder weather advecting westwards across the UK. Good deal of dry weather in the west, but increasing risk of snow showers for eastern and central areas and low PROB of sleet and snow in the far south later. Widespread frosts.

5. Discussion: There remains considerable uncertainty in the evolution during the coming week, with some models, including JMA, and some EPS members maintaining the block, whilst the main signal from the ensembles is for progression of Atlantic frontal systems into the UK. During the trend period, there remains a good signal for trough disruption over the Atlantic with a much colder easterly flow developing. This latter aspect has moderate confidence."

I do again stress this was a midnight briefing and will shortly be superceded!!!

Thank you for that Ian - will help to calm things down here - and show that things are not set in stone and the cold is not far away and will play a major role in our weather in the next coming weeks!

[TEITS]

The truth, is no-one actually knows what we are supposed to be 'catching up with' yet. So I think that any 'I told you so's' are a tad premature and are at least as bad as any cold weather back slapping.

Absolutely spot on Tamara.

Lets be honest the outlook is uncertain. The Met O latest forecast for the end of the week differs to the BBC forecast I have just seen. Into the 2nd week of Feb and the Met O forecast doesn't resemble the UKMO/ECM models whatsoever. Infact im rather surprised at the latest Met O forecast.

The models might be showing a milder trend at the moment but lets not forget only recently all models excluding the UKMO were showing a colder trend. Who knows what +144 might actually look like in a few days time. Some will call this hopecasting or clutching at straws but frankly i've never cared what people think of me.

Edited January 31, 2010 by THE EYE IN THE SKY

[Frosty.]

Its unreasonable to expect the flick of switch to milder weather when this southwesterly comes in, if mild air keeps coming it's going to be a slow process. I do see hints of mildness being pushed back a bit but it is sufficient even by Friday to stop atmospheric rooted cold air affecting us.

I agree with your prudent tone, it will be a struggle for the milder air to override the cold pool we now have with temps only a degree or two above zero. We also have the effects of recent/current stratospheric warming to look forward to in the next 3-5 weeks irrespective of what happens beyond the end of the coming week, a milder interval is probable but mild lovers should not get too comfortable .

[remymartin]

I think to be honest this sort of post which characterises the type of slant you keep putting on things is as wrong as the 'I know better it is going to get colder' camp.

Or are you professing to be having more perceptive foresight and wisdom than the METO?

The truth, is no-one actually knows what we are supposed to be 'catching up with' yet. So I think that any 'I told you so's' are a tad premature and are at least as bad as any cold weather back slapping.

That update clearly states the uncertainty of the pattern, and I am sure if it was weighting in favour of short term cold weather, you would select to say the same.

I think in the circumstances it is a well pitched update, and leaves room like any update should for further changes to occur. Much as they may do tomorrow or the next day.

The short term set up looks very much like Jan 1969 to me - and we know how that -AO pattern followed up.....

If this was a switch to a definitive +AO zonal set up I could understand a much more confident progression to a mild set up. But it isn't. It is a highly volatile one that is full of modelling minefields. And if these are taken too lightly they tend to detonate towards 'one'. Shall we say as politely as possible.

I remember sledging in 1969 did we have a mega northerly in the first week of feb back then?

[SP1986]

but frankly i've never cared what people think of me.

I do like this attitude, I'm ignored all the time - so yep I share that with you!

Who cares?

[The PIT]

Will be interesting too see if this week will provide any frontal snow. Only for the fairly high hills away from Monday but it'll be interesting too see if recent winters past still holds and frontal snow is just a few flakes but the milder air moves in.

The 06 oz looks like the charts from two weeks ago in FI with cold air to the east still coming in.

[BLAST FROM THE PAST]

I'll try and post it again as it was model related. The Country tracks forecast showed synoptically the UKMO version with LP pushing right across the UK into the north sea. However, in the NE 3rd of the UK city temps remained at 5c even on Friday. There isn't sufficient frigid air that those temps would be in place with WSW winds. Maybe the models is right but the forecast didn't really match IMO. Patiently awaiting 12z of tomorrow.

Now not model related but coldest Dec and Jan period since 1982 in Eng and Wales BUT coldest on record for Scotland.........historic winter in the bag I'd say.

BFTP

Edited January 31, 2010 by BLAST FROM THE PAST

[Guest North Sea Snow Convection]

Absolutely spot on Tamara.

Lets be honest the outlook is uncertain. The Met O latest forecast for the end of the week differs to the BBC forecast I have just seen. Into the 2nd week of Feb and the Met O forecast doesn't resemble the UKMO/ECM models whatsoever. Infact im rather surprised at the latest Met O forecast.

The models might be showing a milder trend at the moment but lets not forget only recently all models excluding the UKMO were showing a colder trend. Who knows what +144 might actually look like in a few days time. Some will call this hopecasting or clutching at straws but frankly i've never cared what people think of me.

That interesting METO insight that Ian F posted a page back says it all to me.

The UKMO model may have called the signal for more energy in the shorter term to go into the atlantic correctly, and also picked it up before the other models. but as I suggested earlier, I think it has gone too far with the signal in taking that energy too far east and trying to progressively remove the underlying-AO signal. That underlying signal clearly remains - and I think in that respect the ECM and GFS are nearer the mark, even if they currently have slightly different ways in the short term of dealing with it.

[Lynxus]

Absolutely spot on Tamara.

Lets be honest the outlook is uncertain. The Met O latest forecast for the end of the week differs to the BBC forecast I have just seen. Into the 2nd week of Feb and the Met O forecast doesn't resemble the UKMO/ECM models whatsoever. Infact im rather surprised at the latest Met O forecast.

The models might be showing a milder trend at the moment but lets not forget only recently all models excluding the UKMO were showing a colder trend. Who knows what +144 might actually look like in a few days time. Some will call this hopecasting or clutching at straws but frankly i've never cared what people think of me.

I dont think Hopecasting or Clutching at straws can be said about your comment.

I think its perfectly reasonable to believe that things can change around and show much colder air.

Considering (like you said) all but the UKMO were showing nice cold air. Now its all changed, Whos to say that it wont change around again.

We all know how hard it is to predict the weather at the moment and this is just another example of how complex these winter months have been.

I also think that it should start to show cold again soon. Not based on any scientific data, But just the "feelin in mah bones"

Winter isnt over and im a firm believer that something is gonna sneek up on us whilst everyone is spending so much time looking at the finer detail of something that is either FI or just not gonna happen.

Edited January 31, 2010 by Lynxus

[Ian Fergusson]

Thank you for that Ian - will help to calm things down here - and show that things are not set in stone and the cold is not far away and will play a major role in our weather in the next coming weeks!

I've now seen the updated (12z issue) UKMO 6-10 day briefing based on 00z runs and the 10-15 day guidance remains identical (to that cited above). I'm not going to abstract it here but instead offer just a key section, as follows: "....at this stage the continuity of the EC ensemble is compelling and a cold spell is indicated here, especially by the middle of next week.... Hence few changes are made here to the (midnight briefing) until greater confidence is shown by the operational models and their ensembles."

All sounds simply like prudent science to me, rather than 'back-tracking'.....!

[SP1986]

I agree with your prudent tone, it will be a struggle for the milder air to override the cold pool we now have with temps only a degree or two above zero. We also have the effects of recent/current stratospheric warming to look forward to in the next 3-5 weeks irrespective of what happens beyond the end of the coming week, a milder interval is probable but mild lovers should not get too comfortable .

Re: The strat warming it's got potential however in my experience what we don't have for us is the benefit of staying very cold until then. I find in the scenario like the one that's being forecast now with the advent of an easterly (propagated by southerly), the milder upper air can scupper alot of things, especially at this time of year. Given the setup that's occurring now, the biggest enemy is milder air getting trapped in an easterly high because it's extremely difficult to filter out, and can even prevent things like inversions.

It is amazing how quickly the continent warms up in Spring and how modified easterly air becomes. I recall a few winters back how I was expecting an easterly to deliver a full cold blow -10C the works, yet it didn't even go below freezing, due to trapped cloud cover.

I think were teatering on a tightrope in terms of the patterns that are trying to force their way in. I fully do expect a southwesterly to take command, I don't however expect to be especially mild away from the west and furthermore there is reasonable suggestion for the easterly to take hold after that as that evolution is plausible as lows get cut off from the west.

ps anyone else who says 'Prudent' is going to get an earful from me :lol:

[Mark Bayley]

Absolutely spot on Tamara.

Lets be honest the outlook is uncertain. The Met O latest forecast for the end of the week differs to the BBC forecast I have just seen. Into the 2nd week of Feb and the Met O forecast doesn't resemble the UKMO/ECM models whatsoever. Infact im rather surprised at the latest Met O forecast.

The models might be showing a milder trend at the moment but lets not forget only recently all models excluding the UKMO were showing a colder trend. Who knows what +144 might actually look like in a few days time. Some will call this hopecasting or clutching at straws but frankly i've never cared what people think of me.

Looks pretty similar to the 6z. Cold and showery with something wintry to high ground. Will be interesting to see how this week pans out. GFS shows the risk of snow for quite a few, Tuesday, Thursday and Saturday. UKMO less enthusiastic about this. Who knows how the longer term will pan out. I agree with most that any easterly looks very unlikely. :lol:

[Guest North Sea Snow Convection]

I remember sledging in 1969 did we have a mega northerly in the first week of feb back then?

Yes thats right, Feb 1969 was very cold and snowy with a polar low around the 7/8th Feb and a big easterly afterwards.

I'm not saying that exactly the same is going to happen but like in a +AO set up you can get a cold inversion high in what is otherwise a westerly zonal pattern with a northerly jet stream, you can also get the sort of west based -NAO/-AO set up that brings in mild atlantic air in what is traditionally a cold pattern. These interchange within the same regime of pressure at the north pole that either bottles up cold (+AO) or sends cold to mid latitudes (-AO). With the latter, not everywhere in mid latitudes get lucky all the time. For every northerly or easterly in one place, somewhere else there is a southerly or a westerly

Edited January 31, 2010 by North Sea Snow Convection

[BLAST FROM THE PAST]

I've now seen the updated (12z issue) UKMO 6-10 day briefing based on 00z runs and the 10-15 day guidance remains identical (to that cited above). I'm not going to abstract it here but instead offer just a key section, as follows: "....at this stage the continuity of the EC ensemble is compelling and a cold spell is indicated here, especially by the middle of next week.... Hence few changes are made here to the (midnight briefing) until greater confidence is shown by the operational models and their ensembles."

All sounds simply like prudent science to me, rather than 'back-tracking'.....!

That suggests that NE inroad of LPs will be limited and that a southerly jet will potentially become dominant. interesting to see how the BBC forecasts go this week in relation to the country tracks one.

The crux of the Feb pattern is how far NE will the LPs make inroads.

BFTP

Edited January 31, 2010 by BLAST FROM THE PAST