Model Output Discussion 30/06/2012

[nick sussex]

Disappointing output from the ECM with low pressure stuck over Europe and the limpet Greenland high back in the latter stages, however the differences between this and the 00hrs run are so big especially in terms of heights over Greenland that its hard to have much faith in this operational output.

In terms of the weather for the Olympics Opening Ceremony hard to make a forecast at this moment in time. We should know the definitive trend by tomorrow.

[Snowy Easterly]

its doesn't actually cool down in the south till next weekend though according to the 850s on the ECM, i would still take that, when do we ever get more than a few days of heat consecutively anyway

Edited July 20, 2012 by Snowy Easterly

[Slowpoke]

Pretty poor for my area to be honest, happy for you guys down South though

[camiscool]

Hopefully we will all wake up tomorrow with this gone .

[Snowy Easterly]

Hopefully we will all wake up tomorrow with this gone .

in winter these Greenland high charts would disappear the next morning, but not in summer sadly, i just hope we hang onto the heat for as long as possible and it doesn't get shortened so by mid week the whole country is in some sort of cool northerly

[ANYWEATHER]

Looks like charts from the 1980,s to me! Summer holidays with lots of heat and humidity .more picticularly for the southern half of the Uk, but with torrential thunderstorms. A few more days need to button this, ! Good news for some, bad news for others!

[Snowyowl9]

A chart you`d only dreampt about a week ago.

http://www.wetterzen...cs/Recm1201.gif

A weeks good spell of weather at least,too much looking too far ahead when actually now is when it`s settled down,no rain here for the last 2 to 3 days is a bit of an achievment this summer.

Yes there is showery rain further north and east from that front today.

[phil nw.]

A few members continue to ignore previous requests to stay on topic.

Please keep personal preferences,and Olympic weather talk to the relevant threads and not clog this one up.

Let`s just discuss what the outputs actually show please people.

Thankyou.

[BLAST FROM THE PAST]

I think there is a chance here as we look ahead that there could be some heavy thundery downpours for opening ceremony of the olympics. A warm and thundery LP looks like moving up from the continent....worth watching.

This was showing in deep FI on some previous charts earlier in the week.....

BFTP

Edited July 20, 2012 by BLAST FROM THE PAST

[shedhead]

Please enlighten me, Shed. Because I really don't know what way that you think that the UKMO T+144 will lead to and I suspect that others may share my confusion..

Let me clarify my thoughts for you and any others that might share your confusion then Chio.

If the 144hr UKMO were to verify, I'd expect pressure to leak away quite quickly across the UK in the subsequent 24-48hrs, mainly as a result of LP drifing Nwards out of Iberia and SEwards from near Iceland.

Edited July 20, 2012 by shedhead

[johnholmes]

If you look across all the model outputs so far this evening they all show a shortwave to the nw, the GFS tracks this south into the UK, the UKMO has this tracking away east and being absorbed into the main troughing over Scandi.

So its very likely this shortwave will verify, the uncertainty really is where it tracks once its reached Iceland.

see my pdf this morning?

Let me clarify my thoughts for you and any others that might share your confusion then Chio.

If the 144hr UKMO were to verify, I'd expect pressure to leak away very quickly across the UK in the subsequent 24-48hrs, mainly as a result of LP drifing Nwards out of Iberia and SEwards from near Iceland.

I suspect we may see a rather modified Fax chart for that time later this evening?

[legritter]

evening all .found some time today to study charts and investigate 10 to 15 day forecasts for many world citys in n hemisphere .having recently spent 5 weeks in n america and canada i kept a record of the last severall days of these predictions ,and on every occasion the last 3 days aproximitely we had a heatwave all except once .with the heat wave well forecast 4 days away .but at 10 days away temp predicted were AVERAGE .tonights are certainly throwing up som doughts for the mid and end of next .week .meanwhile when i checked uk met office on internet our guys were out on top [ALSO OUR GANG OF MOD DISCUSSION POSTERS WERE VERY PROFESSIONAL COMPARED TO SOME SITES IN CANADA ETC .]STAYING WITH FRIENDS SO HAD INT ACCESS .SO LOOKING AT ecm and gfs TONIGHT IN MY OPINION NEXT WEEK IS STILL ALL TO PLAY FOR AND IN MY MIND IF WE DONT GET A THUNDERY SPELL AFTER SAY WED ,THE FRIENDS OVER THE CHANNELL WILL OR FRIENDS TO OUR EAST WILL .BUT OF COURSE HIGH PRESSURE COULD BE STUCK RIGHT OVER US AS HINTED AT IN SOME OF TODAYS PAPERS ETC .TONIGHTS MET fax chart will i m sure give some clues and the mornings charts will firm up .theres been ten replies just popped up so as you know i just type with one finger ,cheers all .

[chionomaniac]

Let me clarify my thoughts for you and any others that might share your confusion then Chio.

If the 144hr UKMO were to verify, I'd expect pressure to leak away quite quickly across the UK in the subsequent 24-48hrs, mainly as a result of LP drifing Nwards out of Iberia and SEwards from near Iceland.

Thanks SH. And here was me thinking that you meant high Pressure would establish over the Uk and remain for the rest of summer!

[shedhead]

Thanks SH. And here was me thinking that you meant high Pressure would establish over the Uk and remain for the rest of summer!

Fair point Chio, my apologies, I should have been clearer in my original post.

[Summer Sun]

The ECMWF ensemble run now supports lower pressure to arrive as next week goes on

Most areas should get 3 or 4 summer days but the south will do much better could be a re-run of the warm spell in May

Edited July 20, 2012 by Summer Sun

[Milhouse]

The ECMWF ensemble run now supports lower pressure to arrive as next week goes on

Most areas should get 3 or 4 summer days though!

The ECM op shows a hot day next Friday with some proper heat being brought from off the continent. So, if you say the warm spell begins tomorrow, i make that 7 consecutive days that will have some summerlike conditions.

[bluearmy]

The ECMWF ensemble run now supports lower pressure to arrive as next week goes on

Most areas should get 3 or 4 summer days but the south will do much better could be a re-run of the warm spell in May

i presume we are taking dates rather than sypnotics gavin. quite a strange day.

[damianslaw]

The next few days promise much warmer and sunnier conditions for many especially the SE where it will become very warm as we see a plume of continental heat build northwards behind a slow moving front which will be strung out across the centre of the country come Tuesday.

However, the models are not suggesting the start of a lengthy dry spell or a nationwide heatwave - put simply the next few days are the type of synoptics we tend to see at least once at some stage in the summer - very normal it has to be said, but given the exceptionally poor summer so far, they do appear rather special.

Short term - a slow warm up over the weekend with plenty of sunshine away from the NW quarter of the country where heavy rain and strong winds will spoil Sunday. By Monday a dissapointingly cloudy drizzly zone across n england with bright conditions to the N and S rather than sunny. It will be from Tuesday onwards when the warmth properly starts to build in the SE and maxes will easily get into the high 20's.

As we move through the week the models are suggesting a potential break down from both the NW and S as heights pull away to the west and yet again into Greenland triggered by a shortwave development at the same time pressure looks like lowering over France which could produce some thundery very humid conditions in SE parts.

Longer term - reading others thoughts, and looking at meto update and teleconnections... mmm the signs are for generally cool unsettled conditions to prevail with heights remaining stubbornly strong to the NW and the jetstream destined to stay on a southerly track.. but we shall see.. for a major chance to take place the azores high needs to ridge NE across the country but the models are not showing this. In the meantime lets enjoy the next few days... and hope it isn't another blip like the late May spell.

[Cheese Rice]

It's quite disappointing seeing cloud cover preventing any real warmth North of the Midlands next week. I'm hopeful the high will ridge further north.

As I mentioned a few pages back Yorkshire/Southern NW England is stuck under cloud and at times drizzle while still being warm.

Oh well... the pub run (GFS18Z) likes to offer hope, lets see what that brings!

[A Winter's Tale]

Good evening all.

This Friday certainly wasn't a washout as we've experienced in previous weeks with the only rain today coming in the form of showers in the southern England and Wales. There was a bit of cloud around before skies cleared. Into the night, only the SW Ireland, NW of Scotland and SE England into some northern and central areas will be overcast with good spells of clear skies likely elsewhere. 6C could be possible in the Highland glens but generally tonights minima should be 10-14C.

Early tomorrow morning, NW Scotland should still be overcast and southern and eastern England will generally be cloudy but some breaks in the clouds are likely here. Some good early morning sunshine is likely across swathes of Ireland, Northern England, Southern and Eastern Scotland. As the morning goes on, sunny intervals and sunshine should become a lot more widepsread with the cloud cover breaking up in southern England and north west Scotland. The eastern half of England could be best for clear skies tomorrow morning. Lunchtime looks a similar story but cloud may begin to build in parts of Scotland and in particular the NE where some showers could be likely. Into the rest of the afternoon and again it should continue to be largely sunny. An approching cold front may should increase the cloud cover in Ireland from the west and there should be more clouds in the skies across Scotland. Maximum temperatures should be 17-20C. Into the evening, the cold front moving east will mean that skies should be overcast in Ireland, Western Scotland and the far NW of England, elsewhere should enjoy evening summer sunshine. Tomorrow night is likely to be overcast for much of the north and west thanks to the cold front and western areas of Ireland and Scotland are likely to see the first of the rain. South of Manchester and east of Cardiff should have a clear night. Minimum temperatures of 13-15C.

Sunday is looking like a wet and overcast day for Scotland with overcast skies and the threat of light rain in Ireland, parts of Wales and northern and western England. The southern third of both of England and Wales should enjoy a sunny sunday. Temperatures in the north may reach highs of 19-22C and 23-25C is possible in the SE. The rain in northern areas should break up and become lighter and patchier overnight as it goes on to reach parts of Ireland, SW Scotland and NW England. Only the south of England and the North Sea coast up to the Humber are expected to have clear skies. Minimum temperatures could be 14-17C.

Monday looks generally more overcast for most of us with only the far SE of England likely to get any sustained sunshine. Away from here, an overcast day looks likely with some light precipitation in western areas in the form of showers. Maximum temperatures of 19-22C for most but 24-27C is possible in the far south and east. Monday night again could be a mild one with lows of 14-18C possible. Not much change interms of cloud cover with the far south again having the best of the clear skies. Some light rain should be confined to some western areas and some more persistent rain could be possible in southern areas of Ireland.

Tuesday could be a hot day in the SE with highs of 28-30C possible, elsewhere 18-24C seems feasable. At the moment, the far south of England and possibly Wales are expected to see the best of the sunshine but there could be a few local breaks in the cloud in Scotland. The mainland of Great Britain is expected to be largely dry with the threat of light rain in a few unlucky places but Ireland could have a wetter day thanks to a front. That front is expected to move northwards to bring some light rain for parts of Northern England, Ireland and Scotland for a time in the night. The southern half of England again is expected to keep the clear skies with elsewhere being overcast. Minimum temperatures could be 12-15C in the north and possibly as high as 18C in the south east.

My perspective of the latest outlook for beyond Tuesday is that Wednesday will again see the best of the settled and very warm/hot weather in the southern third of England and Wales. There's a risk of some rain across some central areas of Ireland and England. Some rain could be possible for quite a few areas in Thursday and Friday and judging by latest model runs even in the SE could see persistent and even heavy rain next Friday - but I wouldn't worry yet because it's still a while away and the dates of the rainfall and where it ends up is yet to be agreed. In the past few days, there was an agreement across the models that high pressure out in the Atlantic may move eastwards to bring settled conditions to swathes of the British Isles but in recent runs this seems to have become more uncertain and complicated but again there's plenty more runs to come before we can have a clear picture to what could happen later next week and beyond. There's still an outside chance of high pressure placing itself over Greenland but if I'd imagine that I would be very temporary. The outlook may not be quite as settled as some may hope for but crucially we've got good agreement on the Azores High, another month of summer left, no Greenland high at the moment and I feel very positive that the second half of this summer should not see the same washout conditions as in the first half. Those days look very much behind us and we've got a new set-up for the remainder of this summer and it's nice to have a change for once. The jet may make a few appearances in British shores but my thoughts are that in the second half of summer we'll see spells of showery/cooler/wet weather followed by spells of high pressure and probably more in the way of sunshine and warmth. But that's my thoughts on the 20th July for the remaining 40 odd days of summer and there's every bit of chance that high pressure may place itself over us or in Europe, or in Scandinavia or even in Greenland to put is into another different outlook for the remainder of August and possibly into the start of Autumn. But there'll be sunshine for quite a few of us tomorrow so I advise that you make the most of it as it could indeed be a glorious day and if you live away from the South you may struggle to see the same sunshine or dry conditions for a while. As for the south, you indeed look set for a next 5 days of very dry weather and good amounts of sunshine, some mild or even uncomfortable nights and some very warm/hot temperatures (i.e the first good spell of summery weather since late May). We could even see the first 30C and the warmest temperature of the year on Tuesday in the SE. It could be a wise decision to head to Morcambe beach tomorrow should bring some lovely sunshine but as ever in high pressure scenarios, there's also a nail-bitting wait to see whether's it's going to be cloudy high or a sunny high. And on that high note, I'll leave you with.........

http://www.youtube.com/watch?v=ZedhoqYdfTM

[nick sussex]

Not much change from the GFS 18hrs run apart from the intensification of the precip just in time for the Olympics Opening Ceremony!

Actually this is a shocking output and in one day we've gone from what was looking promising output for the early stages of the games to a Noahs Ark Special!

Hopefully any precip might come a bit later and in the form of showers which gives a better chance of London missing these. Lets hope for better output tomorrow, it would be a real shame to see the Opening suffering a deluge.

Before Noah arrives the weather is set to warm up with southern areas probably holding onto this summer blip until Thursday.

Overall the troublesome Greenland height rise looks like returning, for how long though thats still uncertain.

[Snowy Easterly]

the 18z is horrendous, cools down by thursday, then friday is a washout with temps of 13c or 14c in central england, that will be about the 8th friday on the trot where it has been either wet, cloudy, windy or cool, we have to make the most of this warm snap, or hope that the 18z has gone off on one, dear me

Edited July 20, 2012 by Snowy Easterly

[Alex]

I must say im surprised and dissapointed, however all is not lost yet! Meto 16-30 day update is plenty of fine and dry weather still to come and although the ECM has now come in line, we have rising angular momentum again and GWO pushing into phase 3, MJO into phase 4 - this all equates to better than what is showing. I think more twists and turns can be expected yet!

[shedhead]

As others have quite rightly pointed out the 18GFS maintains the overall theme, making this the 4th run in a row now, so maybe it's time to start accepcting that this is probably the direction we are likely to travel. The weather is no more a respecter of an Olympic ceremony than it is a Xmas Day, what will be will be and at the moment you would have to conclude that rain is looking more and more likely next Friday, as is a return to cooler and much more unsettled weather thereafter.

Edit; Alex, I'd expect something rather different from the next couple of MO 16-30 dayers, maybe even a volte face by Sunday.

Edited July 20, 2012 by shedhead

[nick sussex]

You can see by looking at the ECM ensemble maps at 168hrs the change from the 00hrs run in turns of where these place the high:

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/mean_sea_level_pressure_and_temperature_at_850hpa!168!pop!od!enfo!enplot!2012072012!!/

If its thunderstorms rather than frontal rain moving up from France then its hit and miss, London may get lucky.