Uk General Convective Discussion & Forecasts, 13th March 2013 onwards

[weatherobsuk]

Things initiating quickly in this part of the pennines, waking at 9am it was perfect crystal-clear blue skies and now columns of CU that are visually ascending are visible all around. Its almost as hot this late morning as it was yesterday during the afternoon. 19'c and according to the thermometer rising +1.3'c per hour.

[Coast]

Things initiating quickly in this part of the pennines, waking at 9am it was perfect crystal-clear blue skies and now columns of CU that are visually ascending are visible all around. Its almost as hot this late morning as it was yesterday during the afternoon. 19'c and according to the thermometer rising +1.3'c per hour.

 

That might give you a bit of that SBCAPE to trigger things off - fingers crossed up for you guys up there!

[Stuart]

yes thre a bit of SBCAPE here to but not sure there be anything bar a few shap showers

[NUT]

Tiny little clouds just starting to bubble a little here but nothing major.............yet!

[Coast]

Tiny little clouds just starting to bubble a little here but nothing major.............yet!

 

I suspect you'll be in one of the best areas if it does kick off!

[Methuselah]

I suspect you'll be in one of the best areas if it does kick off!

Not Lincolnshire again!

[Coast]

Not Lincolnshire again!

 

Cumbernauld!

[NUT]

Cloud bubbling up nicely now. Waiitng game see if anything happens.

[Cheshire Freeze]

Nothing kicking off yet. It was always a low risk though.

[NUT]

Nothing kicking off yet. It was always a low risk though.

 

Yeah i'm thinking it may well end up just being 1 of those sunny start/cloud fills in days but mostly stays dry (still time though)

[Cheshire Freeze]

Yeah i'm thinking it may well end up just being 1 of those sunny start/cloud fills in days but mostly stays dry (still time though)

 

Usually we've seen a shower/storm kick off over high ground by now i.e Pennines or Southern Uplands.

 

Probably GFS overdoing dew points as usual.

Edited May 7, 2013 by CreweCold

[NUT]

If anything the cloud's disappearing a bit again (reducing the shower risk probably) actually not a bad afternoon at all it's turned out to be

[weatherobsuk]

Scattered CU clouds have turned more into 'pockets' of larger CU with a hint of banding, but nothing significant visually that's made me keep an eye on things. Radar hinting at a small shower to the SE around the Nottingham area, maybe if that hits the localised CAPE it could provide enough latent moisture to take advantage of the updraughts that are around.

[weatherobsuk]

Also of note is the small MCS system moving out of Holland, if that gets caught in tomorrows low tonight (if that makes sense) there's a good chance vectoring could send it moving NW across Norfolk and into the Midlands. Something to keep an eye on in any case.

[NUT]

Turning cloudier here again and there looks as if there's a shower to the east but it's not heavy or anything major

[BrickFielder]

• Worth keeping an eye on the charts for tomorrow.UKMO synoptic fax charts suggest the rain band sweeping in over night is an occluded front with a further cold front to sweep in later in the day. This suggests we might still be in sort of warm sector conditions (not low 20s temperature but maybe 18C in places).

  Occluded front may well break up and become convective which is perhaps something to watch for in Eastern and Northern areas. Possible low level wind convergence zone around the bristol channel which could spark some convection and develop as it goes in land. Some directional wind sheer through the mid levels, dew points dont look overly cooked, but lapse rates are really only just good enough for storms. Forecast skewt's suggest a cap at 800hpa  - 850hpa height being broken by temperatures in the region of 19C with drier air coming in aloft. Looks a bit touch and go at the moment with instability on the thin side (cape). Too dynamic and marginal to say much more at the moment, but certainly a chance of a storm.

   

[NUT]

We did end up getting a shower here (well OK about 4 drops of rain) but we got something

[Coast]

Let's start this morning with the ESTOFEX forecast, which doesn't specifically cover our area but says:

 

 

Storm Forecast

Valid: Wed 08 May 2013 06:00 to Thu 09 May 2013 06:00 UTC

Issued: Wed 08 May 2013 06:41

Forecaster: PUCIK

A level 1 was issued for Western Turkey mainly for large hail and severe wind gusts.

 

SYNOPSIS and DISCUSSION

 

A negatively-tilted trough that is stagnating over the Central Mediterranean, should undergo a slow cut-off process, with slight amplification to the southeast. Towards the east, a large ridge will encompass most of Eastern Europe, its axis stretching all the way towards Southern Scandinavia. Western Europe will be under the inluence of a large cyclonic vortex, increasing in intensity, its center remaining near Ireland. Closer to the surface, widespread high pressure system will cover most of Eastern Europe, with pressure falling towards south and west.

 

Another area of interest will be Western Europe, namely NW Germany, BENELUX and France. Towards the south, degree of the wind shear should increase, as 20 - 25 m/s westerly flow ovespreads Southern and Western France. However, below 500 hPa, flow will likely weaken considerably, so that 0-3 and 0-1 km bulk shear will mostly stay marginal at best. Combined with meager instability and no concentrated forcing, area does not seem to need a Level 1 attm, albeit an isolated severe wind gust report from a stronger multicell will not be impossible in this setup.

 

 

No forecasts form UKASF, SkyWarn or TORRO (not sure what's happened to those guys???) so straight into the charts over the UK:

 

Aviation weather for today:

 

 

Little or no Mixed Layer CAPE through the day:

 

 

Small areas of convergence, but again nothing of real note:

 

 

Some small areas of lift to the East:

 

 

 

But reasonable levels of surface CAPE up along the NE coast:

 

 

Lower level lapse rates reasonable in places:

 

 

Upper levels almost non-existent:

 

 

I'm tempted to think that you will be lucky to get much in the way of electrical activity today, with anything of note way out in Benelux countries. Not ruling it out completely, but it's a struggle with the mix of ingredients on offer this morning.

 

Edited May 8, 2013 by Coast

[SimonP]

Good to see Estofex forecasts have returned! 

 

As a side note, it's now UKASF's turn - no forecasts will be issued between now and the 17th May, owing to forecasters chasing in the US and scheduled maintenance/updates to the site. 

[Coast]

As a side note, it's now UKASF's turn - no forecasts will be issued between now and the 17th May, owing to forecasters chasing in the US and scheduled maintenance/updates to the site. 

 

TORRO seem to have gone all together?

 

www.torro.org.uk

Edited May 8, 2013 by Coast

[SimonP]

TORRO seem to have gone all together?

 

www.torro.org.uk

 

Heh, seems everyone's having issues! They posted this on their FB page yesterday:

 

Hi all! Just to let you know that we have had issues with our web pages recently, hence why they're down. We can only apologise for this and let you know we're working on bringing them back online. Thanks - Paul.

[BrickFielder]

   GFS is not impressed with today although NMM and the UkMet office suggest some slight possibilites. Low level wind convergence zone towards the south west and extending a little into the midlands is still showing up in the NMM charts.

   It also looks to be giving some moisture pooling.

   Up in the north east the frontal system breaks down and could give a few storms.

   Along the south coast we have vorticity anomaly (trough or front) which could spark some storms if there were any instability  (NMM suggests not).

   Key area could be late afternoon around Cambridge and towards the Wash.

   It all looks a bit marginal with lapse rates only just high enough really for convection. Still there is an outside chance of some storms.

 

Over all it looks a bit marginal for storms today.

[Convective]

Quite a lot of small downpours around all over the place currently. Wonder where, if any, will turn thundery soon?

[NL]

Nice development here in the NE with the radar showing some bright echoes.

[Supacell]

The met office seem to think that there will be thundery showers around this evening but I cannot see that there are the parameters in place for this. Heavy showers yes, but thunder - i don't see it unfortunately. Having said that the eastern coast of Ireland is starting to see some sferics....

 

If there was to be the odd rumble squeezed out in England then i would say somewhere in a line between Gloucester and the Wash within the next few hours going on the charts.