Model Output Discussion 30/06/2012

[phil nw.]

As already requested please keep to model discussion on here please.

Grumbles about the poor conditons and speculative comments are liable to deletion.

Thanks people.

[William of Walworth]

Summer Sun, those links don't seem? to be working fella ...

[William of Walworth]

Has anyone posting here seen any runs or data that in any way dissent from the idea that the suggested HP for early next week will only be very transient?

Any chance of more of a NW/SE divide occuring, with rain/lows tracking further North next week? Or can future output yet evolve towards this?

Speaking selfishly : After so many recent washout outings, I'm pretty desparate as many are on here for a largely dry/pleasant weekend for 20-22July (in my case on the Powys/Herefordshire border).

Yet I'm seeing few hopeful signs for this yet. A two day wonder of High Pressure confined to early in a working week, followed ty a quick return to business as wet and miserable usual towards the w/e, would just be the worst kind of tease. The curse of Fridays and so on. Yet some models are suggesting something like that right now.

Or is later next week still all up for FI grabs still (in the S anyway)?

Edited July 10, 2012 by William of Walworth

[Upgrade]

Expect the 2 day high pressure to be downgraded too...

[Gavin P]

Thanks for your kind words Alex.

I think we WILL get a couple of better days Monday and Tuesday, but beyond that looking increasingly dodgy for Wed-Fri, IMO.

ECM 240hr chart looks poor, to say the least;

http://www.wetter-ze...cs/Recm2401.gif

Edited July 10, 2012 by Gavin P

[nick sussex]

Unfortunately the limpet high over Greenland shows no signs of weakening significantly to allow the jet to track much further north, there is a brief window of opportunity around the 144/168 hrs timeframe when the Azores high ridges ne but even this can't be relied on just yet as the models in recent weeks have tried to take the jet further north in later outputs only to take this further south towards the reliable timeframe.

In terms of FI if you believe in miracles perhaps we might see a more western based negative NAO develop which can steer low pressure on a more ne track, if that does occur then you might see a more nw/se split in conditions but save for that its looking dismal.

If the Azores high does manage to deliver a mini drier blip the flow looks quite humid from the sw so in terms of any sunshine this is more likely further east.

The problem at the moment isn't just those positive anomalies over Greenland but the placement of troughing which after the possible two day drought! looks once again to be centred UK through to Scandi.

[Slowpoke]

ANOTHER washout Friday on the way it seems, the six or seventh in a row...

All improvements are FI yet again so the waiting continues.

[peterf]

well looking at the models and whats to come,iv'e just plugged in the SAD lamp and what a difference that has made to the dining room lol.

[Jason T]

All to painful and ironic this model watching business,If what we have now was current in last winter,Well winter paradise for all, and vice verse from our previous winter to our present summer would be sunny and warm to say the least.One extreme to the other. All to often FI shows us what appears to be distant dream of a pattern change,Hopefully this will be the case soon as current viewing on reliable just shows us Low after low after low and in reality this pattern is not breaking anytime soon.

JT

[Summer Sun]

Summer Sun, those links don't seem? to be working fella ...

Should be fine now

[damianslaw]

Models continue to suggest very much more of the same for the foreseeable future albeit we may see a brief shortlived drier interlude early next week thanks to weak ridge of the azores high.

We remain stuck in the same pattern and that is a jetstream tracking way to the south of its normal position and strong stubborn heights to our NW the consequence is the trough will continue to plague the country. Look at this week and how the trough and associated low pressure is simply being funnelled or squeezed through the north atlantic on a crash course for the country where it then just lingers forever and a day..

The rest of this week will be exceptionally cool for the time of day, some parts of SE Scotland and NE England will be lucky to hit 11 degrees! tomorrow- many a January day when this figure is achieved, shocking for mid July.

Edited July 10, 2012 by damianslaw

[Thundery wintry showers]

Indeed, parts of SE Scotland and NE England look like being decidedly dull, cold and wet again tomorrow. Further south, a bit brighter with some showers but I think it will be predominantly cloudy- GFS has revised its convective/CAPE charts downwards which probably reflects this. After the obligatory depression and frontal rain for Friday, this coming weekend looks rather cool with scattered showers, cloud amounts are quite hard to pin down at this range but Sunday in particular may be a brighter day than we've been used to recently, particularly in the west.

The weather under the ridge from the Azores High would be drier, but still often cloudy and damp (especially in the west) if this evening's GFS was to verify thanks to a shortwave moving east on Monday on the northern flank of the high. UKMO and ECMWF do not show this feature, which would imply a much greater chance of eastern, central and southern England having some sunny spells and comparitive warmth on Monday and possibly into Tuesday as well. I'm not sure which of the models to back as the GFS often overdoes shortwaves at this range but then again UKMO/ECMWF often underdo them.

The longer-term outlook looks like a bog-standard summer westerly type which would promote duller wetter weather towards the NW and drier sunnier weather towards the SE relative to what we've been used to recently. In contrast to earlier in the summer, above average rainfall would not be a certainty in eastern and southern England under such a setup (e.g. the cyclonic/westerly July of 1998 came out quite dry in those areas) but cooler and cloudier conditions than usual are strongly odds-on. However, there are very tentative hints at a possible shift towards a SW-NE tilt to the track of depressions. Most likely this isn't of significance, but if the models turn out to be underdoing this left turn in the jet then we could be in for a more significant pattern change.

[AWD]

The 0z GFS isn't a bad run for the south of the UK. Lots of dry, settled weather after this weekend here, becoming warmer too. The north of the country are prone to more wet weather, especially at weekends, as low pressure systems take a more northerly track, over the northern half of the country.

In FI things settle down for all, as the Azores High comes into play. Aside from last nights 12z run, this has been a predomanent feature in FI of late, so perhaps last nights FI was rogue???

Anyhow, much improved weather on the horizon, more so for the south at first, but eventually to all if FI is to be believed.

Edited July 11, 2012 by Active Weather Dude

[shedhead]

The 0z GFS isn't a bad run for the south of the UK. Lots of dry, settled weather after this weekend here, becoming warmer too. The north of the country are prone to more wet weather, especially at weekends, as low pressure systems take a more northerly track, over the northern half of the country.

In FI things settle down for all, as the Azores High comes into play. Aside from last nights 12z run, this has been a predomanent feature in FI of late, so perhaps last nights FI was rogue???

Anyhow, much improved weather on the horizon, more so for the south at first, but eventually to all if FI is to be believed.

I must be looking at a different 00 GFS, because whilst I see some general improvement next week, the best I can come up with is not as cool and not as wet. As for FI, once again I'm strugging to see any decent prospects there either, with the latter stages in particular taking on an all too familiar look. So in short a definate improvment on what we've endured of late, but nothing special at all and something of a downgrade from what GFS has been touting across the previous 6-8 runs. ECM is not a whole lot different from GFS this morning either. They have also backed off building pressure very far northward next week and post 192hrs it does look as if the Atlantic is set to gather momentum once again.

Edited July 11, 2012 by shedhead

[johnholmes]

my rough notes this morning

Wed 11 july

Ec-gfs

The overall idea of no major trough over/close by the UK continues with ec-gfs this morning, so we now have 5 days with all 3 models showing a similar upper air pattern change. Quite a major one too in my view although it does not signal ‘summer’ arriving other than the odd day here and there.

Little sign of any +ve areas other than minor ones anywhere near the uk, both charts are pretty similar over most of the northern hemisphere along with a similar pattern from noaa over the whole chart should ensure a pattern change within 4-5 days beginning to show up on the actual 500mb charts.

Edited July 11, 2012 by johnholmes

[bluearmy]

my rough notes this morning

Wed 11 july

Ec-gfs

The overall idea of no major trough over/close by the UK continues with ec-gfs this morning, so we now have 5 days with all 3 models showing a similar upper air pattern change. Quite a major one too in my view although it does not signal ‘summer’ arriving other than the odd day here and there.

Little sign of any +ve areas other than minor ones anywhere near the uk, both charts are pretty similar over most of the northern hemisphere along with a similar pattern from noaa over the whole chart should ensure a pattern change within 4-5 days beginning to show up on the actual 500mb charts.

indeed JH and a pattern change should not be siezed upon by anyone expecting a flip from dreadful to fantastic. what could well happen is that whereas the past months have seen any uncertainty in the modelling post day 6 being quickly filled by troughing, the same situation could well see ridging take precedence as we see the runs develop. i am concerned that deep fi naefs continues to promote the greenland anomoly becoming quite strong again and no sign that high anomolys gain any foothold near the uk. that could make the change to one of no upper trough a temporary one.?

[Milhouse]

After the dire conditons of the last week or so its a relief to see some light at the end of the tunnel and thats being reinforced by the netweather forecast which points towards a more settled end to the month with the Azores high coming into play more often. For the start of next week its a case of dry and settled for southern Britain and cloudy and cooler further north with the threat of further rain here. However even here we should see some warmer weather if the high managed to ridge far enough north. For the end of next week its looking like the next low will come crashing through bringing a cool and shower end to the week. After that, the ensembles point to a return of something warm.

But surely now the spell of dry and warm condtions is looking odds on for early next week. Should easiy see 25c in the south with us being very close to the warmest time of year and there should be 4 dry days Sunday to Wednesday for southern parts. The settled conditions look like extending into Scotland for a time but it will be more shortlived.

[Weather Boy]

I know that pattern matching is something that rarely seems to come off (and apologies if this is a little OT) but it seems to me that the obvious comparator is summer 2007. Although that was not as thoroughly wet as this one it was synoptically similar.

In that year we saw a benign and normal end of July and August without anything special (except for remarkably resilient cloud at the end of the month that kept it extremely cool - but I doubt that can be relevant for looking for a match, it being some six weeks off).

[shedhead]

indeed JH and a pattern change should not be siezed upon by anyone expecting a flip from dreadful to fantastic. what could well happen is that whereas the past months have seen any uncertainty in the modelling post day 6 being quickly filled by troughing, the same situation could well see ridging take precedence as we see the runs develop. i am concerned that deep fi naefs continues to promote the greenland anomoly becoming quite strong again and no sign that high anomolys gain any foothold near the uk. that could make the change to one of no upper trough a temporary one.?

I think you are right to be concerned too ba. Certainly FI has promoted more trouging than ridging across the last few run, so IF correct much of week 4 now looks more unsettled than settled, especially the farther the north you go. If nothing else you would think the Law of Averages would suggest we should have a much better 2nd half of Summer, but whilst there are still green shoots of recovery, decent growth still looks a fair way off.... sound familiar??

[Glacier Point]

I know that pattern matching is something that rarely seems to come off (and apologies if this is a little OT) but it seems to me that the obvious comparator is summer 2007. Although that was not as thoroughly wet as this one it was synoptically similar.

In that year we saw a benign and normal end of July and August without anything special (except for remarkably resilient cloud at the end of the month that kept it extremely cool - but I doubt that can be relevant for looking for a match, it being some six weeks off).

2007 is a reasonable comparison in terms of both June's being marked by a very low angular momentum (June 2012 was the lowest value since 1984). However, we are intriguingly poised here. With the tropics running a little more active than normal and El Nino starting to reach 'official' status, the atmosphere must at some time begin to respond. This will ping angular momentum and we should expect some strong GWO phase 4 projections, introducing a bit more of westerly progression of upper troughs and ridges and a more favourable tilt to the jet.

[Thundery wintry showers]

For the short term up until Sunday, not much change really, a belt of frontal rain moving into the S and SW tomorrow and spreading over most of England on Friday, showers and some brighter intervals further north, and then brighter showery weather for all parts over the weekend. Showers are likely to be heaviest and most thundery towards the south during Saturday with the north seeing fewer showers although also cooler temperatures, fewer showers generally on Sunday.

The 2-day high pressure has been revised further south today thanks to the models picking up on shortwaves running across to the north of the high pressure, as first happened with the GFS yesterday evening. It may still end up relatively settled, dry and warm near the south and east of the UK but the shortwaves are likely to produce trailing weak fronts which may give extensive cloud, occasional drizzle and an emphasis on high night-time minima. At present both GFS and ECMWF suggest that the ridge of high pressure may cling onto the southeast which may give eastern and southern England a shot at some sunshine and daytime warmth next Wednesday (perhaps 22-25C possible?), which is worth watching as sometimes the models can be over-progressive at bringing in subsequent lows. On the whole, though, the long-term outlook looks pretty "westerly" to me with only tentative hints at a SW-NE tilt developing in the track of depressions.

I do agree that there is a fair chance of us getting a relatively quiet benign August, like those of 1998 and 2007 for instance- both months were generally dry, and some parts of the UK were sunny (the south in 1998, NE England in 2007) although it was often cool and breezy. August 1993, following a notably "westerly" July, was a cooler version of the same sort of thing.

[A Winter's Tale]

Good afternoon.

Well today has been yet another day this summer with at least somewhere in the British Isles experiencing dull and damp conditions. The main regions today are Central, South Eastern Scotland and North Eastern England where we've had some persistent and at times heavy rain and there have been showers affecting Ireland, Southern, Central and Eastern England too aswell as some coasts. I'm afraid that in the forecasts for the rest of today, tomorrow, Friday, Saturday and Sunday that rain will be present in certain areas however towards the end of the week we should probably not see quite as widespread and heavy condtions as in past days. Also, beyond this weekend it seems like more settled conditions than of late is likely but as it's still relatively far away we need to follow how the evolution of this potential change occurs in the model output and in doing so we may learn more about what the period beyond this could hold - we could be heading for a more significant change but it's vital we focus in more short-term changes in order to find out about what the future may bring.

This evening, it seems like the best of any brightness will be found in the southern half of Britain aswell Ireland and some Scottish western coasts. There'll be a few showers in Ireland despite some bright spell and temperatures should be at around 12C this evening. Across the Irish Sea over to Wales, here too there will be a few showers and sunny spells with some cloud cover lingering onto some coasts and in particular the south of the country with temperatures typically at 15C. South across the Bristol Channel to SW England, here this evening could be overcast at times with a few period of brightness around the coastal regions and some light localised showers are possible and temperatures will be similar to Wales at around 15C. Along the south coast of England here too there'll be periods of both sunshine and cloud cover with less showers. Further north of here into central England will probably see the best of the brightness this evening with longer spells of clear skies - or cloud cover if your unlucky. Here too there'll be some showers but the heaviest and most widespread of the showers will be found around Manchester and along Eastern Areas. Temperatures here will vary from 18C in the London area to 14C over the Manchester. The north of England is likely to be overcast with some rain the in far north and east of the region. Temperatures here will be a disapointing 10-12C. In Scotland, there'll be rain in the SE into some Central areas aswell as some areas of light rain in the NE, SW, NW and Shetland coasts. A cloudy day here too although there'll be some brightness in some western regions and temperatures will range from 11-15C.

Into tonight, we lose the rain in SE Scotland, the showers die away and we're left with quite widespread clear skies over much of Ireland, Wales and England. SW England, some western regions of Wales, northern coasts of Ireland, coasts and some inland areas of Northern and Eastern England may see cloud cover overnight and much of Scotland will remian overcast with some heavy persistent rain in NE. I'd say that East Anglia and the Midlands will be best for overnight clear skies.

Tomorrow morning, early on it should start dry, sunny with some rain in the NE of Scotland and clouds in coastal, Northern and exposed regions. But we'll see an area of persistent rainfall knocking on the door of the SW and as the morning goes on we'll see this rain affect Southern parts of Wales and much of the SW of England. Skies will become increasingly more overcast with a few sunny intervals although the east may continue to see some good brightness. Scotland will continue to be overcast with a few clear spells and the rain in the NE should die away as the morning goes on. By lunchtime, we'll see temperatures of 15C in Glasgow to 19C in London with only the northern half of Scotland having disapointing values of 10C due to cloud cover.

Tomorow afternoon, cloud cover will continue to increase (but plenty of areas will still be able to hang onto good periods of sunshine) as we see the rain in the south spread. Much of the south coast, SW, S Wales will see persistent and at times heavy rain and this will move further north and east to affect other parts of Eastern and Central England. North of this rain, we have drier conditions but quite cloudy in Wales and a mix of overcast and sunny spells between East Anglia and Cumbria. In the south of Ireland there could be some patchy rain with overcast skies, in northern Ireland there may be some sunny intervals. The far NE of England should remain overcast with some drizzle and Scotland should be largely overcast with a few showers. The rain in the south will continue to move NE tomorrow evening to affect London and into tomorrow night Wales, Ireland and Central England will experience this rainfall. To the south of this, it will remain overcast and the only real clear spells overnight will be the far north of England and south of Scotland. Overnight temperatures of 11-14C.

Friday, for once, Scotland will see some brightness but the coasts and NE may continue to remain overcast with some light rain. Even the North and NE of England will remain dry and see some brightness. From Manchester in the north to London in the south, rain will affect much of Wales and Central England and some areas could see some heavy rainfall. The south coast could remain dry and even sunny with a few showers threatening the SW. In Ireland, Friday looks like being wet and dull. Temperatures will be disapointing in the N of Scotland with 10-13C, but parts of Ireland and the south of Britian could see temperatures of 16-18C.

Friday night, the rain will become less persistent and heavy but plenty of areas will be vulnerable to damp condtions overnight. The midlands, NW England, parts of Ireland and W Scotland look like seeing some overnight rain and showers could affect East Anglia, the NE coast and the SW. Some clear skies overnight are forecast to be situated over eastern Scotland and parts of Wales and South/Central England. Temperatures quite cool at 10-13C.

On Saturday, at the moment it seems that outbreaks of rain and showers are likely to be dotted all over much of England and Wales and the north of Scotland with some brightness in areas such as the SW and between those showers. Generally, skies should be overcast except a few areas in the NE of England and West of Scotland. Temperatures will range from 14C in the north to 20C in the south.

Saturday night will continue to see precipitation situated over eastern and central England with the north, south coast and SW of the country escaping the rain. Wales should be dry except a few showers and Ireland should be dry other than a few coastal showers and it's a similar story with Scotland with some light rain in the NW coast. The best of the clear spells are to be found in the far south, parts of Ireland and a good chunk of Scotland.

At the moment, Sunday looks like being a largely dull day with some damp condtions along western regions and in particular the far north of Scotland and SE of England. Widespread dry condtions in Central England and Scotland is likely too. For most, temperatures will be in the region of 15-18C. On Sunday night, it again looks overcast with rain in NW England, SW Scotland, N Scotland and some north sea coasts. Quite a cool night with 10-12C.

So severe heavy rain looks unlikely for most but some persistent and heavy rain will affect quite a few areas although the next two days should see the worst of this in the south. Some dull and overcast days are likely too but tomorrow and on Friday plenty of areas will see some sunshine. Quite a few areas will also remain dry for long periods too depending on the focus of the rainfall. It's not inspiring week but there are some plus sides that relentless heavy rain looks unlikely and some bright spells is likely too for some. Now, we've see this northern blocking for a long time and we're a due and ending to this current weather pattern. Next week, it looks like high pressure will move in from the south and southern areas of Britain are in the firing line for some settled conditions. We need to watch the timing, positioning, duration and evolution of this possible settled period of weather as who knows what will follow next week - could this be the start of a new pattern or will this just be a brief period of settled condtions as the high pressure to our NW prevails? We need to wait and find out - it'll be intruiging to see what follows.

[AWD]

Another settled and summery FI from the 12z GFS today. Settled and warm over most of the country if this were to verify.

Until then we still have a few days of rain to get through, maybe some problematic totals in places. From Sunday onwards it is an ever improving picture for the south, although there is a blip later next week when low pressure does return for a couple of days again, bringing more widespread rainfall.

For the north it takes a little longer to improve, hanging on the low pressure and showery conditions into next week here. However the settled conditions do prevail and influence much of the country towards the end of July.

So, an ever improving picture for the south, with warm summery weather becoming more prominent and rainfall becoming the new "blips". For the north, a little longer of the curren pattern before things turn summery here towards the end of the month.

[Summer Sun]

Hints of some summer like weather in FI from GFS but the short term remains unsettled

[Summer Sun]

Hints from UKMO tonight of high pressure trying to build

It doesn't look too bad for the south for a few days next week if this doesn't downgrade