Uk General Convective Discussion & Forecasts, 28th August 2012>

[Chris W]

Probably some turbulence too, unless they can fly a fair way around it. Here's hoping it doesn't cause much damage for locals' and holidaymakers' sakes.

[Coast]

I'm heading to Rome on Tuesday, so i'm watching this low pressure system near Italy. Can i expect some thunderstorms?

Maybe in a weeks time, although it bubbles along with some chances for the next few days:

Looks like quite a bit of rain:

http://www.netweather.tv/index.cgi?action=world;loc=1192914~rome,%20Lazio,%20ITALY;sess=

[Karl83]

Looks like the eye candy is beginning to creep back in. Could be interesting after the weekend. Nice to see lots of energy down south so I hope it makes its presence felt here, should it materialise.

[snowfluff]

Can't say the outputs look particularly inspiring myself, currently. Profile on GFS and UKMO-GM doesn't really look unstable around the period in question, thanks to ridge aloft and a lack of real heating/moisture at low levels.

That was like taking candy from a baby,you cruel man

[Coast]

Looks like the eye candy is beginning to creep back in. Could be interesting after the weekend. Nice to see lots of energy down south so I hope it makes its presence felt here, should it materialise.

Hmmm, I'm still being reserved about it:

Not even that convectively special in the South:

Admittedly its only one model and very far out, but the trend is away from any convective potential at the moment I guess.

Here's the closest I can see it getting currently:

[Karl83]

Let me re-iterate. When I said South, I meant Spain/France areas, NOT England. I was only mentioning this as its nice to see the CAPE colours getting closer to the UK again (albeit too far out to take totally seriously) and my hope is we get that over here. I hope this clarifies my previous post.

[Coast]

Let me re-iterate. When I said South, I meant Spain/France areas, NOT England.

Well I'm not sure I'll be travelling that far this week, but with sunny and warm weather likely in most of the UK, it will be nice enough here despite not getting the storms further down into Europe. Anyway, I'm not sure I would recognise a TStorm now after being denied for so long!!

[Sprites]

i heard on the news that a decaying cat5 hurricane, may affect the uk late september, with severe gales heat waves and heavy rain, it was on the BBC so it must be true.

[The watcher]

i heard on the news that a decaying cat5 hurricane, may affect the uk late september, with severe gales heat waves and heavy rain, it was on the BBC so it must be true.

I would guess that is a call by none other than "he who must not be named". For one, it is not unusual for the UK to get decayed hurricanes at some point in Autumn, it is the matter of how decayed they are. I would expect a few ex-TS's or Hurricanes would have gave the UK heavy rain and severe gales by the end of November.

[Coast]

Still nothing in the foreseeable:

Small disturbance around the 10th, but currently not enough to get anyone excited.Back to the jigsaw puzzles.........

[AWD]

Patiently sits twiddling his thumbs awaiting just the remotest signs of any convective activity!

[Jane Louise]

And me lol. I wonder when the next lot will be! September used to be good here for storms years ago but not anymore. Oh well, an Atlantic storm when due will do for me in the meantime.

[PolarWarsaw]

The UK in general has had quite an active storm period this summer. It's been relatively exciting with numerous chases and opportunities country wide for the last 10 or so weeks. Im not surprised things have quietened down somewhat - it has to be expected!

[Coast]

+ = A relatively quiet period in September (foreseeable) with sun at last

- = No storms on view either for the foreseeable......

You can't have it all ways!

[Robbie Garrett]

+ = A relatively quiet period in September (foreseeable) with sun at last

- = No storms on view either for the foreseeable......

You can't have it all ways!

I'm happy with this Summer, I can't complain can I. But the MCS imports are one that seem to be a distant memory, we never even had a chance this year compared to last years 2 failed attempts in August that we sat up half the night watching disintegrate mid-channel then head east.

Thankfully we haven't had to go through that heartache this year.

[Coast]

Thankfully we haven't had to go through that heartache this year.

Well there is that of course, but I've still seen too many charts and SkewT's +24 that have held great promise for East Sussex only to turn to nowt I think I'll right off this year and see if anybody does charts for 8 months time and start getting excited about 2013!

[paul m]

Well there is that of course, but I've still seen too many charts and SkewT's +24 that have held great promise for East Sussex only to turn to nowt I think I'll right off this year and see if anybody does charts for 8 months time and start getting excited about 2013!

Apparently we are due 5 hurricanes, Brimstone will fall from the skies but no bloody storms for up here lol.

[Coast]

Apparently we are due 5 hurricanes, Brimstone will fall from the skies but no bloody storms for up here lol.

I suspect Eastbourne will survive intact too. Interesting to see what the ex-hurricanes might do to our weather, current charts have nothing much for real convective weather so let's hope the output isn't reflective of the actual for a change.

[AWD]

Looks like we might have something to look for in the coming week as pressure drops and LP systems make inroads into parts of the UK.

Nothing of note seen yet, but at least there are now chances for something to appear rather than zero chance under HP.

[Coast]

Leslie looks like going further West of us?

Michael may grace us with a glancing presence:

Not a lot of chances coming up according to GFS, Scotland fairing moderately better:

That blip late next week may come or go of course.

Quiet down South

[Stuart]

been a long time

Synopsis:

An elongated area of low pressure approaches from the Atlantic, beneath a sharp upper trough. At the surface, a weakening cold front moves eastwards into western Britain. Ahead, slight destabilisation in the mid-levels is anticipated.

Discussion:

... CS & SE ENG, S & E MIDLANDS, EAST ANGLIA ...

Advection of high ThetaE will occur in the mid-levels, steepening lapse rates in the upper portions significantly. With the approach of a shortwave, destabilisation will result in an area of Ac and AcCas moving eastwards across the aforementioned areas during the afternoon and early evening hours.

Given past model performance with mid-level destabilisation, it is possible that isolated showers may develop within this AcCas zone, but with very dry surface air and large dewpoint depressions, this will probably result with virga and very little precipitation reaching the surface. Such mid-level convection is unlikely to be deep enough for sferic activity, and hence no threat level has been issued.

Models are all in more general agreement with mid-level showers developing over the Brest peninsula/Channel Islands during the afternoon, migrating northeastwards and becoming better organised as they move through the English Channel and into the southern North Sea by the end of the forecast period. Such area of showers may graze parts of Kent, Sussex and Essex, but the chance of sferic activity is currently considered too low to warrant a SLGT here.

... IRELAND, NORTHERN IRELAND, SW SCOTLAND ...

Behind the cold front, slightly cooler mid-levels accompanied by an upper trough will overspread the forecast SLGT area. Scattered showers, occasionally merging along embedded occlusions, may be capable of sporadic sferic activity given several hundred J/kg CAPE.

Low-level convergence and backed surface winds, especially across eastern portions of the area, coupled with 30kts DLS, of which 25kts is in the lowest km, may allow cells to exhibit supercellular characteristics, with the potential for a funnel or weak tornado.

http://www.ukasf.co.uk/storm-forecasts/220

[Coast]

been a long time

It has Stuart but I'm not sure if it offers a big chance?

ESTOFEX show a very weak area over Ireland backing the UKASF, but it's a low chance:

Maybe in Western Scotland around Glasgow at a pinch later?

[gottolovethisweather]

Has anyone been looking at the radars of late, take a look towards Brest? There are sferics in the English Channel and moving NE'wards up towards parts of the South Coast. An increase in turreted cumulus type clouds here in Newbury, Berkshire and just up the road into East Wiltshire.

Could something be brewing, I wonder. A max of 22.8c here so far, with somewhat yo-yoing dew points, albeit rather depressed at around 14c/15c.

Weather09, I see you are lurking, what is your take on it all.

I am obviously clutching at a large clump of straws but it does look rather interesting according to satellites and radars, are other parameters in place for action?

[Andy Bown]

An increase in turreted cumulus type clouds here in Newbury, Berkshire and just up the road into East Wiltshire.

Yes some lovely AltCas patches drifting SW-NE from late morning, definitely an interesting occurence.

[johnholmes]

a few spots just now from a mix of CuSc Ac Cas