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

[Mesoscale]

Just damp here in Southampton, look at those storms in NE France and Belgium they are really going off!

[Supacell]

Some heavy showers around across the southern half of Wales and the SW currently, ahead of the main rain band presently crossing Ireland. There was a rogue sferic detected at around 5am near Swansea so the potential in there for the odd rumble, nothing significant though (with regards to thunderstorms) although the winds today could certainly be significant.

 

I haven't got time to post up charts but there is likely to be some heavy showers later this evening across northern England, especially to the west of the Pennines just to the south of the low centre as it moves west to east across southern Scotland. Could be some very squally winds in this, perhaps gusting 60mph and the odd weak storm may be thrown in, although again the risk is a low one.

 

Northern Ireland may be better placed as there looks to be some weak instability here during the afternoon. 

Edited May 9, 2013 by Supacell

[Coast]

I can't see much in the way of electrical storms for today, but the wind should keep people on their toes. Also, in a land far far away......

 

[Panayiotis]

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

 

 

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.

 

Hi where can I access these charts or do I need to subscribe to Netweather?

Edited May 9, 2013 by Panayiotis

[Coast]

Hi where can I access these charts or do I need to subscribe to Netweather?

 

Well everyone needs to subscribe to Netweather of course!! :lol: But some of the specific charts posted for people's reference, can be found here:

 

http://lightningwizard.com/maps/

[NUT]

I can't see much in the way of electrical storms for today, but the wind should keep people on their toes. Also, in a land far far away......

 

 

A snow symbol!  

[Coast]

Probably have to wait until mid-next week for the next widespread thunderstorm risk day,

 

 

 

 

[Convective]

Nice area of sharp showers circling the centre of low over Northern Ireland.

[weatherobsuk]

Sleet falling here momentarily as the frontal passage made its way through, temps dropping below 7.5'c currently and I must say that was quite a surprise to be seeing anything wintery considering what we've had the past few days.

[Coast]

Did you guys catch this on BBC Two last night, skip to 45 mins if you just want the weather related stuff:

 

http://www.bbc.co.uk/programmes/b01pqmxw

[Panayiotis]

Well everyone needs to subscribe to Netweather of course!! But some of the specific charts posted for people's reference, can be found here:

 

http://lightningwizard.com/maps/

Thanks for this, being at the age of 17 and not owning a credit card etc I cant subscribe to Netweather but I will be in the future!

 

 

Did you guys catch this on BBC Two last night, skip to 45 mins if you just want the weather related stuff:

 

http://www.bbc.co.uk/programmes/b01pqmxw

V.Interesting watch!

[Convective]

Nice line of showers running south of here. Nothing too heavy but quite scenic to watch bob up and down as they move east into North Wales

 

[Chris.R]

Occasional moderate convective showers here on a strong wind.

[Panayiotis]

Early days but Tuesday is definitely a day to watch for some convectional activity with the centre of the low over most of the UK, the cape is looking good and a fairly unstable atmosphere could spark off some storms:

 

Edited May 9, 2013 by Panayiotis

[Coast]

Morning storm fans!

 

Starting with ESTOFEX today, they only have Ireland in their sights:

 

 

 

 

Storm Forecast

Valid: Fri 10 May 2013 06:00 to Sat 11 May 2013 06:00 UTC

Issued: Thu 09 May 2013 21:26

Forecaster: TUSCHY

A level 1 was issued for parts of Lathvia, Lithuania and Estonia mainly for an isolated tornado and large hail event.

 

A level 1 was issued for NE-Italy, extreme S-Austria and W-Slovenia mainly for heavy rainfall amounts.

 

SYNOPSIS

 

The upper streamline pattern features a transient phasing of the upper jets over W-Europe, before high-over low blocking over E/SE-Europe forces both jets to diverge over S-C Europe into a nothern branch (towards the Baltic Sea) and a southern one (towards N-Africa). 

 

Low geopotential heights prevail over NW-Europe as numerous vortices round the base of a major longwave trough. One vortex exits the North Sea during the start of the forecast and approaches Norway and Sweden from the SW. This will be the main synoptic feature, which results in organized DMC. Otherwise, this pattern is not supportive for an organized severe thunderstorm risk over the rest of Europe.

 

 

 

 

Mid-level aviation significant weather charts are clear for us:

 

 

Small amounts of CAPE in Ireland later:

 

 

Still a lot of shear about from the low:

 

 

and convergence out West:

 

 

Precip seems to be mainly in Ireland later too:

 

 

 

Small area of spout interest off the coast of Ireland too:

 

 

Lapse rates up out there:

 

 

 

All in all not great chances for a thunderstorm today. Ireland obviously stands out for anything that might get going, but I think that may be limited to some gusty wind, maybe hail and heavy, thundery rain in the West of the UK later  - possibly a very low risk of a spout.

 

[VillagePlank]

Very reasonable chance of some overnight thunderstorms in the SE tonight. Kent/E & W Sussex in touch with relatively moist and warm air,

 

 

Along with this strong vertical motion across the whole atmosphere profile indicates cell development,

 

500hPa,

 

 

700hPa,

 

 

925hPa,

 

 

Kent is favoured most, but upper air development does slide North and East towards Essex and E Anglia, with cells starting life out over Sussex (so may well grow them, but turn into T/storms over Kent)

 

Special mention for E Kent, E Anglia more towards 3am, too: could be some nice sea-CG overnight photos around the Dover/Calais area, and over the N Sea near Essex/E Anglia.

Edited May 10, 2013 by Sparkicle

[Sprites]

A kent clipper tonight then?, perhaps heavy showers with hail and thunder tmrw for eastern england. Although when the bbc starts mentioning thunder it often is just rain.

[VillagePlank]

Main problems are uplift development not really associated with normal bouyancy parameters, so skew-t looks like a no hoper, even though it does develop some MLCAPE (at midnight!!), LI suggests vertical motion should be downwards. Also dew-points and theta-w are right on the boundary of marginal. As well as all this NAE has the instability cutting straight through London, MetO have it through Kent, and GFS has it as coastal channel stuff.

 

I think it will happen somewhere, but where? Somewhere in the SE. Sharp showers overnight are likely, but will they develop into t/storms?

 

Edited May 10, 2013 by Sparkicle

[Sprites]

Yes someware in the S.E. of France lol

Edited May 10, 2013 by Sprites

[VillagePlank]

It looks to me as if the upward motion is being determined by a convergence zone in quite brisk winds,

 

Edited May 10, 2013 by Sparkicle

[BrickFielder]

   Not that impressed with mid level lapse rates today.

   Now compare that with overnight ones.

 

   Tropopause top looks limited today as well.

 

 

Some chances of some sharp showers today. Forecast SkewT's show limited cloud tops though.

 

Overnight we do appear to get some mid level instability, but it will not be surface based. Even here mixed level instability is limited  (MLCape). Foecast SkewT's look more frontal than convective, but there is a good chance of some heavy possibly thundery showers overnight  (not convinced myself).

 

Tomorrow sees a jet streak approaching and crossing the southern part of the UK. The jet streak exit region over the north and central UK should see some divergent winds aloft and hence conditions for lift.  There is also a suggestion of a surface moisture trough. Too early to say much about tomorrow at this point though, but northern and perhaps some central eastern areas late afternoon look best.

 

[Coast]

I think it will happen somewhere, but where? Somewhere in the SE. Sharp showers overnight are likely, but will they develop into t/storms?

 

Chances look very small (or less) to me for anything in the way of a thunderstorms overnight in the SE. Two Skew T's for the SE area at at midnight are not at all encouraging currently:

 

 

 

NMM from Netweather not showing signs either:

 

 

 

Although lapse rates are up a bit and tickling Kent later:

 

 

GFS not convincing either:

 

 

 

Maybe we should be looking at Thursday and beyond (a long shot, a long way away)?

 

[VillagePlank]

The chances that I thought possible were down to this cold front,

 

 

Leading to air going upwards, particularly at 700hPa.

 

 

Happy to be wrong

 

Edited May 10, 2013 by Sparkicle

[Coast]

 

Happy to be wrong

 

 

Would rather it came out right!! :lol: 

[VillagePlank]

Would rather it came out right!!

 

So would I! Still, always good to stick your neck out, once in a while