Model Output Discussion

[Costa Del Fal]

Not quite sure if I agree with your assesment of this weeks weather, too me it looks we are on course for a very unsettled week with showers or longer spells of rain. You say its far from a washout but Wednesday looks like it will be a miserable day for most of Scotland with persistant rain and cool temperatures. Elsewhere we should see convective showers so sunshine in between is likely but it certainly will be a poor week in terms of warmth and dry weather but an interesting week for convective lovers like you and I are Luke.

So its an "poor" outlook for summer but an interesting one weatherwise potentially.

Yes it does look a bit iffy at times especially for Scotland and the far west but for the majority of us, its showers or relatively short bands of rain it looks to me. It sure is poor for complete dryness and warmth after today but in terms of properly being Poor acorss the country it isnt imo bar perhaps the far North and far west. For much of England at least, it is certainly sunshine and showers.

[ribster]

He hasn't said that it would give us dry, warm and settled conditions. All he has said is it could be the sign of improvements...

No, you are quite right, he didn't explicitly say so, but I would argue that it was very much implied. Anyway, before then it looks wetter and cooler more or less everywhere, what happens beyond Sunday is anyones guess.

[johnholmes]

The models showing our unsettled potentially thundery weather for this week and thereafter an improving situation a slow improvement, with a potential does of more summer weather, whether it be dry or warm. To me this summer is shaping up very different to 2007 to 2009, 2010 not too bad but a declining summer none the less. IMO the rest of summer will be a better version of summer 2010 for July onwards, but not perfect, not a classic, but warmer, August last year was quite cool.

I found two links, both different but show vaguely the same scenario dont know why there is two.

the second one is a later issue, see top right of each output

[Downpour]

Yes it does look a bit iffy at times especially for Scotland and the far west but for the majority of us, its showers or relatively short bands of rain it looks to me. It sure is poor for complete dryness and warmth after today but in terms of properly being Poor acorss the country it isnt imo bar perhaps the far North and far west. For much of England at least, it is certainly sunshine and showers.

Someone on the Site That Shall Not Be Named has earmarked a line from Cornwall to Lincs as the screw zone for the heavy showers, with London & the SE again the driest as the region picks up more stable air from the channel. I could really use some rain for my newly laid lawn but as we have guests Friday I'm still clinging to the hope that we may escape at least on Friday night. But that's hopecasting. Air temps looking okay all week here though.

[mushymanrob]

low heights over greenland might not directly mean we will get a settled warm sunny summer...but it helps! ok we can have poor summers with low pressure over greenland, but arent we more likely not too?... its that wretched thing that keeps the jet south and aimed either at us or south or us resulting in an unsettled summer. so gavin banging on about pressure drop over greenland and implying itll be better prospects for us might not be a law, but it is a damn good step in the right direction, because i dont think we can get a 'proper' summer hot spell whilst thats in place.

the pattern continues, ridge/breakdown/showery low/ridge .... maybe if things go right one of these ridges might actually build into something more sustained, especially if we do lose the heighs over greenland. however, this mornings runs are at odds. the ecm looks the most plausable, resulting in a flat jet whilst the gfs 00z is a mess which tbh i think shouldnt be taken seriously... i expect subsequent runs to be more logical.

[Gibby]

UKMO continues to show a showery theme in its output this morning as Low pressure takes up residence near the UK until later in the weekend. By Monday though a weak ridge is shown moving in from the west killing the showers in the process.

GFS also shows the same showery theme and ridge by Monday. The ridge looks weak and transitory though as after a few days Low pressure trundles back in off the Atlantic to affect the weather by producing more rain and heavy showers as it becomes slow moving near Scotland by 240hrs. For the remainder of the run we watch the progress of the Low amble south through Britain and only very slowly away east keeping the UK in unsettled and showery conditions to the end of the run with temperatures suppressed in the cool airflow.

ECM is less progressive than GFS in the low pressure next week and though the general pattern of GFS is shown it keeps the centre of the second low further North and East keeping the rain and showers at their worst there. In the south and west it would be predominantly dry though never very warm with a NW component to the wind and quite a lot of cloud at times.

In Summary the operationals have backtracked a little from yesterdays marked improvements. Instead after a brief ridge early next week we see GFS bringing a second stubborn low pressure over our shores and further days of cool showers while GFS though drier is keeping things generally unsettled principally in the North and East though even the south and west could see a few showers in a cool NW flow.

[95 Degrees]

Nothing really interesting on the models this morning, all average, we're just waiting for that bang on the models and for an Azores High to suddenly show in FI on a model and stay there the next day and then the others come on board, yet to happen but this current pattern hasn't got much more to give IMO.

[mushymanrob]

the gfs 00z is a mess which tbh i think shouldnt be taken seriously... i expect subsequent runs to be more logical.

... and the 06z obliged!

[ribster]

low heights over greenland might not directly mean we will get a settled warm sunny summer...but it helps! ok we can have poor summers with low pressure over greenland, but arent we more likely not too?... its that wretched thing that keeps the jet south and aimed either at us or south or us resulting in an unsettled summer. so gavin banging on about pressure drop over greenland and implying itll be better prospects for us might not be a law, but it is a damn good step in the right direction, because i dont think we can get a 'proper' summer hot spell whilst thats in place.

Don't disagree mushy, yes a step in the right direction, in the same way that a high pressure/blocking over greenland in winter is a step in the right direction towards a cold spell, but other things need to fall into place. Would just be nice to read some model analysis by those more learned than myself, rather than 'signs of lowering heights over greenland' and pictures or links showing it day after day, which I can go and view for myself anyway. And before anyone says it, yes I realise it might be time to use the ignore feature.

Edited July 5, 2011 by ribster

[johnholmes]

to give you a brief answer Ribster

The 500mb charts I use, usually fairly reliable, for the 10-14 day period, occasionally a bit longer, really show no sign of a major change.

The ECMWF-GFS issue this morning is about the most optimistic looking one I've seen for a couple of weeks. All that shows though is that the 500mb vortex is predicted to slowly fill by day 10 with SLIGHT signs of the Azores upper ridge starting to build, along with the 500mb contour flow decreasing in speed a bit.

Nothing there to suggest there is going to be a spell of real warmth but POSSIBLY the first signs that something might develop. If the pattern continues on the next 3-5 days outputs, is backed up by the NOAA version each evening, and the further out teleconnections swing into a more positive view, then PERHAPS something to look forward to. Myself I doubt anything significant is going to develop before the end of the month IF then.

The ECMWF-GFS link below

http://www.meteo.psu.edu/~gadomski/ECMWF_0z/hgtcomp.html

remember it will change when the next output is issued as its not been copied and pasted simply linked

Edited July 5, 2011 by johnholmes

[Weather Boy]

The current GFS 0z run looks quite good if we look beyond the coming unsettled spell to, say Sunday/Monday which should be withing the reliable. It looks as if we have HP dominating nationwide until deep FI

However, I am concerned that it does something quite unlikely. If you see the chart for Tuesday http://www.netweather.tv/index.cgi?action=nwdc;sess= HP covers the UK, but out in the Atlantic is a Low that you would expect to steamroller into Scotland, but instead it goes far north leaving the vast majority of us still with HP: http://www.netweather.tv/index.cgi?action=nwdc;sess= before a slow breakdown in deep FI.

For me, the ECM is a little more convincing in the earlier time frame, with the LP moving to Scandavia a little faster. However, it too has the same LP to the West of Scotland on Tuesday http://www.netweather.tv/index.cgi?action=ecm;sess= and it does something even weider which is having the LP just fill and disappear virtually overnight.

Taking the big two together at face value on just this run, you might think that we were in for a fairly long settled spell, but I find the runs by that late stage (which is borderline FI) somewhat unlikely.

The GFS ensembles also seem to back a more sustained higher level of pressure, and also reasonably high temperatures with few cold or LP members.

[mushymanrob]

to give you a brief answer Ribster

The 500mb charts I use, usually fairly reliable, for the 10-14 day period, occasionally a bit longer, really show no sign of a major change.

The ECMWF-GFS issue this morning is about the most optimistic looking one I've seen for a couple of weeks. All that shows though is that the 500mb vortex is predicted to slowly fill by day 10 with SLIGHT signs of the Azores upper ridge starting to build, along with the 500mb contour flow decreasing in speed a bit.

Nothing there to suggest there is going to be a spell of real warmth but POSSIBLY the first signs that something might develop. If the pattern continues on the next 3-5 days outputs, is backed up by the NOAA version each evening, and the further out teleconnections swing into a more positive view, then PERHAPS something to look forward to. Myself I doubt anything significant is going to develop before the end of the month IF then.

The ECMWF-GFS link below

http://www.meteo.psu.edu/~gadomski/ECMWF_0z/hgtcomp.html

remember it will change when the next output is issued as its not been copied and pasted simply linked

are you writing off summer then john? :lol:

[Alex]

I think summer will end up rather average this year, some warmer brighter days and some wetter cooler days - no washout, yet no prolonged heatwave however places further north and west may end up with another poor summer. It's a shame but I can't see the pattern changing much, maybe august will end up better but we need fundamental shifts. It's even more disappointing as I thought we were odds on for something decent this year!

The 06z is an example of this changeable summer and shows exactly what I say above.

[TonyH]

Real warmth? Two short spells of that in the past 10 days. Sometimes its happening here and now while others doom and gloom on.

[Weather Boy]

I think summer will end up rather average this year, some warmer brighter days and some wetter cooler days - no washout, yet no prolonged heatwave however places further north and west may end up with another poor summer. It's a shame but I can't see the pattern changing much, maybe august will end up better but we need fundamental shifts. It's even more disappointing as I thought we were odds on for something decent this year!

The 06z is an example of this changeable summer and shows exactly what I say above.

Not sure I agree. The 06z looks remarkably similar to the 0z that I commented on a few posts above. In the longer term (i,e from c. Sunday -depending on where you are) onwards it looks rather settled, if not especially warm to a significant, but rather surprising degree.

Someone commented that next week looks like a re-run of this week, which looks a reasonable comment, except with a later unsettled spell and potentially a longer settled spell thereafter.

[Summer Sun]

GFS Currently has temps of around 20c to 22c from the Midlands South and 15c to 19 North of the Midlands for the 3 day's from and including Sunday with GFS often under doing the temps I would add another 2c or 3c onto those, though I suspect cloud cover will be a big factor, under cloud maybe those temps would be seen but in any clear sunny periods maybe 25c or so in the South, that's if High pressure moves in next week of course.

[mushymanrob]

Real warmth? Two short spells of that in the past 10 days. Sometimes its happening here and now while others doom and gloom on.

.... and if the odd warm day doesnt co-incide with weekends/time off then its pretty much wasted. what we are starved of is a proper hot spell that lasts a week or longer. its looking increasingly likely that this year will fail to deliver such a spell, 5 years since the last (for most of the country...the southeast has fared rather well in recent years).

Not sure I agree. The 06z looks remarkably similar to the 0z that I commented on a few posts above. In the longer term (i,e from c. Sunday -depending on where you are) onwards it looks rather settled, if not especially warm to a significant, but rather surprising degree.

Someone commented that next week looks like a re-run of this week, which looks a reasonable comment, except with a later unsettled spell and potentially a longer settled spell thereafter.

trouble is theres no real support from the teleconnections (again if im wrong here then im pleased to be corrected, im no expert) that theres anything settled for more then an odd few days as a ridge between two depressions cross over us.

[Weather Boy]

trouble is theres no real support from the teleconnections (again if im wrong here then im pleased to be corrected, im no expert) that theres anything settled for more then an odd few days as a ridge between two depressions cross over us.

If that's right, then they agree with me, for reasons in my original post. The ensembles are generally supporitve though. Surely ECM plus GFS plus ensembles are collectively quite a bit of support? Also the teleconnections weren't too great over the winter, IIRC.

How can we look at the teleconnections please?

[Geordiesnow]

.... and if the odd warm day doesnt co-incide with weekends/time off then its pretty much wasted. what we are starved of is a proper hot spell that lasts a week or longer. its looking increasingly likely that this year will fail to deliver such a spell, 5 years since the last (for most of the country...the southeast has fared rather well in recent years).

But on average per decade, how many summers do actually have a hot spell? I just think like winter time, expectations are too high for the extreme too happen whilst normal summer weather gets well and truely ignored. This past week has been warm and it certainly felt like summer just like in winter, a cold dry frosty spell feels like winter.

Yet again, I refuse to write off a month because the model output does not show what I ideally like too see. There is still a chance for another warm spell to develop and we got all the way until September to enjoy warm weather, yes the days are not as long then but warmth can still be enjoyed.

The trend does appear after this unsettled week for things to turn drier but as of yet, it probably won't turn any warmer but this can of course easily change.

[Summer Sun]

But on average per decade, how many summers do actually have a hot spell? I just think like winter time, expectations are too high for the extreme too happen whilst normal summer weather gets well and truely ignored. This past week has been warm and it certainly felt like summer just like in winter, a cold dry frosty spell feels like winter.

Yet again, I refuse to write off a month because the model output does not show what I ideally like too see. There is still a chance for another warm spell to develop and we got all the way until September to enjoy warm weather, yes the days are not as long then but warmth can still be enjoyed.

The trend does appear after this unsettled week for things to turn drier but as of yet, it probably won't turn any warmer but this can of course easily change.

Yes looks as if things will settle down by Saturday, then we find ourselves in a North westerly flow for a few day's.

[ANYWEATHER]

A "Bland" 12zgfs imho, pressure starts to rise early next week, but to my eyes it really leaves us in a "no mans" land with enough instability to produce us some showers. The only hint of a strong Azores high is right into the end of the run which of course is Fantasy Land..... <_<

[Summer Sun]

GFS Right at the end of FI is in it's own world, would be nice if it came off.

[95 Degrees]

A "Bland" 12zgfs imho, pressure starts to rise early next week, but to my eyes it really leaves us in a "no mans" land with enough instability to produce us some showers. The only hint of a strong Azores high is right into the end of the run which of course is Fantasy Land..... <_<

It may well be well into FI ANYWEATHER, and it may well be gone by tomorrow or the day after, but it's certainly something worth smiling about all the same, especially as a persistent Azores high would likely bring very hot air at this time of year, depending on the setup and prevailing wind direction of course.

[Downpour]

Mushyman Rob - the last two weekends have been warm

and fine so not really sure what you are getting at.

[ANYWEATHER]

Mushyman Rob - the last two weekends have been warm

and fine so not really sure what you are getting at.

Yes, But you do Realize that you live in one of the Driest Cities Of Europe....