Model Output Discussion 14th May 2012 Onwards

[William of Walworth]

>>Robbie, the way I'm reading your post, and those charts, option 1 of your two (or something close-ish to it) for later on into June certainly isn't to be ruled out yet at all, which is as good as we're going to get or that far ahead. Even if the chances are no better than 50/50 between options 1 and 2, that can't be that bad, so for now I'll cling to some optimism for later. All usual FI caveats apply obviously, but thanks for those thoughts.

[johnholmes]

For anyone wanting sun, dry and warmth for the start of June-toddle off to your travel shop 'because it ain't very likely you will see much in most parts of the UK. The 3 500mb charts, not totally similar, but near enough for an unsettled and at times cool outlook to be the order of the day.

It is so sad after all the hard work and hopes for this weekend as well before the 7-15 day outlook after so much sun and warmth recently.

Edited May 31, 2012 by johnholmes

[shedhead]

No real point in trying to sugar coat the overnight runs, they are (at least for those of us seeking fine, warm and sunny weather) pretty dire, with the first fortnight of June having an all too familiar look of recent Summers about it. The return of a southerly tracking Jet and the reluctance of pressure to weaken across Greenland is disappointing and frustrating at this stage, so without being too melodramatic it's hard to see us getting much decent weather out of the first two weeks of June and if the longer range FI is to be believed even the 2nd half may struggle to see a significant pattern change. We've all seen just how quick things can change recently, with the warm/very warm spell virtually coming out of nowhere, but from what I can see now "1 down and 2 to go" looks the most likely soundbite we'll be hearing in about 3 weeks time.

[Interitus]

Just looks like the typical June 'European Monsoon' which will affect all of the country before tending towards more of the NW-SE split. Meanwhile, Poland and Ukraine look like they will probably be warming up nicely for the Euro 2012 finals.

[Methuselah]

Is 9C in June really all that ridiculous?

http://www.netweathe...ction=gfs;sess=

Have I got the link right? If not, look at 2nd June 1975...

[shedhead]

Is 9C in June really all that ridiculous?

http://www.netweathe...ction=gfs;sess=

Have I got the link right? If not, look at 2nd June 1975...

An imfamous day indeed....... http://www.lccc.co.uk/news/this-day-in-1975-snow-stopped-play/2894 but 75 went on to be a cracking Summer, almost up there with the legendary one a year later.

[Methuselah]

An imfamous day indeed....... http://www.lccc.co.u...opped-play/2894 but 75 went on to be a cracking Summer, almost up there with the legendary one a year later.

But I wonder how a few on here would have viewed that summer's prospects, based on that particular chart?

[shedhead]

But I wonder how a few on here would have viewed that summer's prospects, based on that particular chart?

Absolutely Pete, poor starts to June or even poor June's do not guarantee poor summers overall - hopefully Mr D might be able to put some meat on those bones. However, sticking to the model output (as we're supposed to do in here) there's nothing to suggest anything even half decent for the forseeable, which in truth takes in the next 10-14 days at least, so even now I'd be fairly confident in saying (at least as far as dry, warm and sunny is concerned) 2 down, 11 to go.

Edited May 31, 2012 by shedhead

[Methuselah]

Absolutely Pete, poor starts to June or even poor June's do not guarantee poor summers overall - hopefully Mr D might be able to put some meat on those bones. However, sticking to the model output (as we're supposed to do in here) there's nothing to suggest anything even half decent for the forseeable, which in truth takes in the next 10-14 days at least, so even now I'd be fairly confident in saying (at least as far as dry, warm and sunny is concerned) 2 down, 11 to go.

Agree with that, SH; the foreseeable does look a tad 'mixed'...As usual, my main 'ray-of-hope' is that all the models keep chopping-and-changing from run to run - at least in the detail? FME, most major patter-changes take the models (and us?) a bit by surprise...

[Thundery wintry showers]

Having looked over the model outputs there seems to be some disagreement between the GFS and the UKMO/ECMWF. The UKMO has joined ECMWF in suggesting a cyclonic south-westerly regime after the Jubilee weekend which would promote rather warmer conditions than the GFS is showing, though those charts don't give much indication of frontal positioning so I'm not sure whether the weather would be mostly showery or cloudy/wet. The GFS does look remarkably reminiscent of recent summers with southerly tracking lows and a lot of persistent rain.

Issues have crept in with the Jubilee weekend itself with a frontal system spreading over the south during Saturday/Sunday, giving some persistent rain- how far north the band gets is open to question. Further north, cool with some sunny intervals (probably sunniest and least cool in the west) and an increasing number of showers, most places staying dry on Saturday/Sunday but many catching some showers on Monday.

[tinybill]

Having looked over the model outputs there seems to be some disagreement between the GFS and the UKMO/ECMWF. The UKMO has joined ECMWF in suggesting a cyclonic south-westerly regime after the Jubilee weekend which would promote rather warmer conditions than the GFS is showing, though those charts don't give much indication of frontal positioning so I'm not sure whether the weather would be mostly showery or cloudy/wet. The GFS does look remarkably reminiscent of recent summers with southerly tracking lows and a lot of persistent rain.

Issues have crept in with the Jubilee weekend itself with a frontal system spreading over the south during Saturday/Sunday, giving some persistent rain- how far north the band gets is open to question. Further north, cool with some sunny intervals (probably sunniest and least cool in the west) and an increasing number of showers, most places staying dry on Saturday/Sunday but many catching some showers on Monday.

http://www.meteociel...&ech=108&mode=2

i know this morning the bbc saying sunday not looking good now so we might have to wait till friday to see if its going to be a washout !!!

Edited May 31, 2012 by tinybill

[Roadrunner]

Good post TWS. In your opinion what will be the northern extent of the band of rain for Sunday? Modelled on the 0z GFS to be slap bang over London.

[Robbie Garrett]

>>Robbie, the way I'm reading your post, and those charts, option 1 of your two (or something close-ish to it) for later on into June certainly isn't to be ruled out yet at all, which is as good as we're going to get or that far ahead. Even if the chances are no better than 50/50 between options 1 and 2, that can't be that bad, so for now I'll cling to some optimism for later. All usual FI caveats apply obviously, but thanks for those thoughts.

Yeah, that's correct from what I can see... this probably relates to the fact that high pressure over Greenland doesn't really get going and the NAO heads neutral/positive. (and I think that is the key) But it happened last year, and it just built strongly again and we had a dismal July/August/September and it wasn't till end of September we got some decent weather into October with 30*C on consecutive days, with 25*C for 2 weeks.

If June does play out how I think it will, it will sort of be reminiscent of June 2005 somewhat..

But only option 2 is being shown at the moment, and that's the Greenland high rebuilding.

Return to Neutral NAO -

Return to Negative NAO -

Something has definitely changed in the atmospheric conditions over the last few days, prompting a consistent Greenland block, with Atlantic monsoon conditions till at least 22nd July. Only a few days ago was it showing July to be very very nice. Something to watch though, as I understand it's not what everyone wants to see but that's what it's showing.....

Edited May 31, 2012 by Robbie Garrett

[NorthNorfolkWeather]

Agree with that, SH; the foreseeable does look a tad 'mixed'...As usual, my main 'ray-of-hope' is that all the models keep chopping-and-changing from run to run - at least in the detail? FME, most major patter-changes take the models (and us?) a bit by surprise...

Time and again we see changes pop up, almost out of nowhere. It just goes to show that the models are just that, models. They cannot hope to forcast every nuance and, as you say, many times pattern changes take us by surprise.

I personally like John Holmes 500mb anomaly views, they seem to be one of the best leading indicators, but even they can fluctuate quite a lot.

We seem again to be in a period where FI isn't much more than 60-72 hours, with the models disagreeing as you get further out from that

[johnholmes]

Time and again we see changes pop up, almost out of nowhere. It just goes to show that the models are just that, models. They cannot hope to forcast every nuance and, as you say, many times pattern changes take us by surprise.

I personally like John Holmes 500mb anomaly views, they seem to be one of the best leading indicators, but even they can fluctuate quite a lot.

We seem again to be in a period where FI isn't much more than 60-72 hours, with the models disagreeing as you get further out from that

Yes, with the cautions I always state they are, in my view, by far the most reliable indicator for what the UPPER air pattern is likely to be 7-15 days ahead. The forecaster then still has the problem of TRYING to get the atmosphere below 500mb down to the surface correct. That is by far the most difficult. It always was 40 years ago doing the Fax chart for 24 hours ahead. It is still not that much different even at similar time scales as we are disocvering as we try to discover what the BH weekend weather will do. It is certainly true at the 7-15 day time scale even if we get the right idea about 500mb the surface can be nothing like correct. But at least with the 500mb sort of sorted its a much better start than not having that. My latest check will be done later today and another chekcstarted tomorrow. Hopefully as the number of checks increases it may start to indicate those instances and who knows why where the 500mb charts also are far from the actual. Its fascinating to me and I hope just the same to those without the professional training.

Edited May 31, 2012 by johnholmes

[MP-R]

So the models do show quite a bit of doom and gloom for next week, the GFS in particular with it's establishment of a cyclonic SWerly flow. FI is also pretty poor but then again, this time last week (when I got back from Madrid), this coming weekend was showing as an absolute stonker with deep red uppers and high pressure over the UK, transferring eastwards next week - oh how that has changed! So time will tell how long this unsettled spell lasts, just a shame the coolest conditions HAVE to come on the Sunday and Monday.

Really quite cool this time next week though by the GFS:

http://www.netweather.tv/index.cgi?action=charts;type=gfsh500;sess=

[Mapantz]

The remnants of tropical storm Beryl are showing up ont he GFS now. Quite possible that it will get absorbed in to the Atlantic flow and head this way next week, albeit, weaker of course.

[shedhead]

Time and again we see changes pop up, almost out of nowhere. It just goes to show that the models are just that, models. They cannot hope to forcast every nuance and, as you say, many times pattern changes take us by surprise.

I personally like John Holmes 500mb anomaly views, they seem to be one of the best leading indicators, but even they can fluctuate quite a lot.

We seem again to be in a period where FI isn't much more than 60-72 hours, with the models disagreeing as you get further out from that

FI might be considered 60-72hrs with regard to detail, but I'm afraid as far as the overall pattern is concerned there's currently a very strong consensus that rather cool, unsettled and often wet weather will predominate the next 10-14 days. We just can't get away from that at this stage I'm afraid.

[NorthNorfolkWeather]

FI might be considered 60-72hrs with regard to detail, but I'm afraid as far as the overall pattern is concerned there's currently a very strong consensus that rather cool, unsettled and often wet weather will predominate the next 10-14 days. We just can't get away from that at this stage I'm afraid.

Hi Shedhead,

Not really disputing what you say, but I would bet that it will not be as cool and as wett as is currently progged by the models. Add into the mix the remnants of Beryl, as any ex tropical storm tends to confuse the models and I for one would not be surprised to have a different view of the 5-9 day outlook in 5 days time.

[NorthNorfolkWeather]

Yes, with the cautions I always state they are, in my view, by far the most reliable indicator for what the UPPER air pattern is likely to be 7-15 days ahead. The forecaster then still has the problem of TRYING to get the atmosphere below 500mb down to the surface correct. That is by far the most difficult. It always was 40 years ago doing the Fax chart for 24 hours ahead. It is still not that much different even at similar time scales as we are disocvering as we try to discover what the BH weekend weather will do. It is certainly true at the 7-15 day time scale even if we get the right idea about 500mb the surface can be nothing like correct. But at least with the 500mb sort of sorted its a much better start than not having that.

Hi John,

I've found it fascinating since I was a child and still find it so now. As you say, 500mb to the ground is very difficult to do, and you can see it in the way the FAX charts vary, often by quite large degrees between when they are published at T120 to when it becomes the analysis chart.

On the models, I feel that the type of talk that ofetn happens in the winter months, about Northern blocking not being handled well applies to the models now as well, as someone else posted, just a week ago this weekend was going to be great, now it's looking poor, but even this close the models can't decide whether it's a washout or a showery regime.

Only one answer......

wait and see

[The Northern Ramper]

The charts for next week and beyond are not what GP was suggesting a week ago, quite ominous by his absence from this thread of late and the delayed summer forecast.

Going to Devon next Saturday for two weeks and it looks dire.

[shedhead]

Hi Shedhead,

Not really disputing what you say, but I would bet that it will not be as cool and as wett as is currently progged by the models. Add into the mix the remnants of Beryl, as any ex tropical storm tends to confuse the models and I for one would not be surprised to have a different view of the 5-9 day outlook in 5 days time.

I'd like to think so too and I remember thinking and saying as much in early April..... we don't need reminding what happened thereafter do we...

Things should not be quite as bad then tho and of course even in the most hideously unsettled spell you'll see the odd decent day or two, but that's about the only straw I can find to clutch at this stage.

[Thundery wintry showers]

Good post TWS. In your opinion what will be the northern extent of the band of rain for Sunday? Modelled on the 0z GFS to be slap bang over London.

Looks most likely to be the Midlands on the basis of the latest runs- the tendency has been to shift it further north turning a cold but fairly bright Sunday into a washout over the southern half of England.

[Summer Sun]

Rather unsettled from GFS again this afternoon, only deepest FI (mid month) does high pressure attempt to build

http://www.null/ds/gfs.htm

[PubliusEnigma]

I would take those temperature charts with a hefty handful of salt! Also you're not suggesting those temperatures, you're reading off what the GFS says, which at this stage looks to be -3-4c off the mark. A max of 13-14c in central and southern areas is complete nonsense IMO. Before someone suggests it, yes I do enjoy the warmth, and I'm not in denial over the cooler spell coming up, however I'm not the only one on here who knows those maximums are too low - it's a GFS habit.

It looks like it will be even colder than I thought with News 24 calling for only 10oC or 11oC in most southern areas on Sunday.. Add in the wind-chill and I'd say that would feel more like 5oC if you are out and about celebrating the Jubilee. There were many doubters here as to how cold it was going to get.. But a drop of 17 or 18oC in just 4 or 5 days is really something to write home about. It would seem the weather is resetting somewhat to the default english summer, for which other europeans claim we are famous for..

Even a week later Great Britain languishes under the Summer upper trough which seems to want to embed over our neck of the woods for what seems like weeks on end. Almost all of Europe is warm and sunny even the far north of Scandinavia, yet we will be stuck with temps in the mid teens and longer spells of rain..

My instinct tells me this pattern can become entrenched during June, how long for is anyones guess. The MO 15-30

dayer seems to indicate that the unsettled cloudy and wet regime may well last until 29th June, with the worst of the

unsettled gloomy and wet weather in the south. There was a lot of chatter on here a short while back about a hot june

the ensembles would indicate a flow generally west or north westerly between the rain bands.

England the cold man of Europe.. 7oC in Heavy rain could see Sleet fall over higher elevations as the cold air aloft is dragged down to surface levels..

If those temps verify we would see over a 20oC drop in temps in 7 days.. Remarkable !

Edited May 31, 2012 by PubliusEnigma