25-26th October 2011 - Convective/storm Discussion & Reports

[Nick F]

Heavy showers and thunderstorms look to develop across southern Britain today, please discuss and add your reports here.

Convective / Storm forecast - Issued 25/10/2011 11:00

Forecast Summary Map

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Valid: 25/10/2011 06:00 - 26/10/2011 06:00

Headline: ... THERE IS A RISK OF THUNDERSTORMS FORECAST...

Synopsis

Large upper low and colocated surface low over western Britain drives a cyclonic SW flow across the British Isles, by 12z ... cold front lies across NE Scotland with showery troughs moving NE across England and Wales.

... SW ENGLAND, SE ENGLAND, E ANGLIA, LINCS and S WALES ...

Upper low across the W/SW will spread increasingly cold upper air/steep lapse rates in from the SW across the Sern half of England and Wales today. Scattered heavy showers and thunderstorms will therefore develop across southern England and south Wales by lunch-time and continuing through the afternoon into the overnight period. Shortwave trough(s) moving NE will enhance convective activity and thunderstorm development, fairly strong upper flow towards eastern England and 30-40 knots of DL shear should be sufficient for some loosely organised convection capable of producing some strong wind gusts, hail and CG lightning, particularly across coastal central S/SE England this afternoon and through tonight. However, without a more robust indication of instability and stronger wind shear in the lowest km, no severe weather is anticipated. Heavy showers/t-storms across SE England will transfer north across E Anglia and other areas of E England by dawn.

Issued by: Nick F - Forecaster for Netweather

[Harry]

[Nick F]

Some nice Tcu building up here over south London in the bright sunshine. Showers are getiing going now across central-S England.

[Lauren]

What he said ^^^^.

Beautiful and sunny here at the moment, but some interesting clouds building up. I am scared to get optimistic this year after so much disappointment.

[Robbie Garrett]

Anyone in Area A1 will get Isolations of +SHRA/+TSRAGS with localised Embedded CBs from 01500ft-3000ft on the TROUGHS. According to the TAFs it's going to happen between lunchtime and midnight. Looking at the frontal synopsis anything between 1800 and 6am tomorrow, so any lightning should light the sky up.

LONDON LUTON EGGW 250500Z 2506/2606 17012KT 9999 SCT025 PROB40 TEMPO 2506/2508 BKN009 TEMPO 2512/2603 7000 SHRA PROB40 TEMPO 2515/2603 3000 +SHRA TSRA BKN012 BKN020CB BECMG 2603/2606 23012KT LONDON/CITY EGLC 250801Z 2509/2518 17009KT 9999 SCT025 TEMPO 2511/2518 6000 SHRA PROB30 TEMPO 2515/2518 3000 +SHRA +TSRA BKN014CB LONDON/GATWICK EGKK 250503Z 2506/2612 17008KT 9999 SCT025 TEMPO 2511/2612 7000 SHRA PROB40 TEMPO 2512/2612 3000 +SHRA TSRA BKN014 BKN025CB BECMG 2609/2612 20012KT LONDON/HEATHROW EGLL 250503Z 2506/2612 17010KT 9999 SCT025 TEMPO 2511/2612 7000 SHRA PROB40 TEMPO 2513/2524 3000 +SHRA TSRA BKN014 BKN025CB BECMG 2601/2604 22007KT LONDON/STANSTED EGSS 250500Z 2506/2612 17012KT 9999 SCT030 PROB40 TEMPO 2506/2508 BKN010 TEMPO 2512/2603 7000 SHRA PROB40 TEMPO 2515/2603 3000 +SHRA TSRA BKN014 BKN025CB BECMG 2603/2606 23010KT PROB30 TEMPO 2609/2612 7000 SHRA

Harry seeing as you're alive, I am guessing the location of that Trough and the wind direction is good for French Imports??

Some nice Tcu building up here over south London in the bright sunshine. Showers are getiing going now across central-S England.

Let's hope it builds throughout the day, Diurnal is not till 3/4pm when things should be at max pot.

Edited October 25, 2011 by Robbie Garrett

[Chris K]

Met Office predicts T-storm this evening for Bristol, where forecast radar doesn't quite agree...with it heading eastwards before reaching us.

Anyone know what the likelyhood of us seeing anything here is? Or is it more of a S/SE coastal affair?

[philglossop]

Looking at the IOW radar, something is brewing around Brest. Still it's early doors yet!

Edited October 25, 2011 by philglossop

[Robbie Garrett]

Looking at the IOW radar, something is brewing around Brest. Still it's early doors yet!

TAF's have all just been downgraded, PROB30 TEMPO 2514/2523 17015G25KT 4000 +SHRA TSGR

[Snowkissed]

I can confirm that we are experiencing thunder and lightning and rain. A lovely storm! (Well as lovely as storms can be)

[Robbie Garrett]

I can confirm that we are experiencing thunder and lightning and rain. A lovely storm! (Well as lovely as storms can be)

Cries!

[Flash Elvis]

I can confirm that we are experiencing thunder and lightning and rain. A lovely storm! (Well as lovely as storms can be)

Are you winding us up.....I cannot see any lightening strikes anywhere on Radars

[Harry]

Harry seeing as you're alive, I am guessing the location of that Trough and the wind direction is good for French Imports??

HAHA!!! LOL!!! Yeah I've been fairly absent lately, combination of too much work, relationship, studies, social life and the likes...plus a distinct absence of convective potential!!

I think imports are decent bet...the Channel should serve to beef up any potential showers/storms/thundery rain, however it becomes a little bit less certain as things progress over land. The synopsis from Estofex and Nick F are promising, however UKASF is much more conservative with the focus around coastal areas.

Predicting how far inland any action gets will be difficult IMO. Normally 15-20 miles is a reasonable estimate, but with rapidly falling uppers it could continue well inland. In short, I don't know

[wimblettben]

As I predicted earlier the worst we have had so far here is just on and off light showers.

Still, looks quite dark to the south.

[Robbie Garrett]

Nice big Convective CB to my South West, probably over Streatham area.

[MP-R]

Very dark clouds to the west which were heading this way from the SW then veered straight northwards so that sun has stayed out all the time. Hoping for just a little push further east to affect this area.

[wimblettben]

I can confirm that we are experiencing thunder and lightning and rain. A lovely storm! (Well as lovely as storms can be)

Could you please confirm whether or not this is true and actually happening?

How come the radars aren't showing anything?

[Robbie Garrett]

Harry seeing as you're alive, I am guessing the location of that Trough and the wind direction is good for French Imports??

HAHA!!! LOL!!! Yeah I've been fairly absent lately, combination of too much work, relationship, studies, social life and the likes...plus a distinct absence of convective potential!!

I think imports are decent bet...the Channel should serve to beef up any potential showers/storms/thundery rain, however it becomes a little bit less certain as things progress over land. The synopsis from Estofex and Nick F are promising, however UKASF is much more conservative with the focus around coastal areas.

Predicting how far inland any action gets will be difficult IMO. Normally 15-20 miles is a reasonable estimate, but with rapidly falling uppers it could continue well inland. In short, I don't know

Haha!! Also your PM feature doesn't work anymore, wont let me PM you.

Yeah I am looking at it at the moment, the trough is just starting to come over the channel. Will be south of Brighton at 1800z according to the Aviation section of the MetOffice. Hence the convective showers being set off all over the south at the moment. Looking at the CAPE levels, it seems to be mostly over the channel or Le France, annoyingly.

So unless we get some big imports, it's a non-event this one unfortunately.

[Stormyking]

Ahhh good to be back in the Storm area, hope we get some thunderstorms, good luck fellow storm lovers

[Robbie Garrett]

This is what's over me at the moment, rather slow moving and going darker!!

[Chris K]

Nice to see the usual gap approaching Bristol area. Heavy showers to the SE heading N and a bigger clump to the SW heading off towards S Wales if it follows its current path. A nice circle of nothing on radar developing that's approaching us haha...

Story of 2011.

[Purplepixii]

ooooh I must confess I do have my fingers crossed for something stormy - it's been far too long without any! There are strikes showing on Meteox albeit only a few - but here's hoping!

[wimblettben]

ooooh I must confess I do have my fingers crossed for something stormy - it's been far too long without any! There are strikes showing on Meteox albeit only a few - but here's hoping!

Those strikes look very scattered to me.

Seems certain however that we will get heavy showers later as the showers move northwards.

[Mapantz]

There's been thunder & lightning and some good downpours here. Looks as though some more is pushing up from the channel.

[Robbie Garrett]

Huge anvils across London by the looks of things.

[A.J]

Hmm....looking at the NW radar now with more than just a passing interest....Some interesting developments in the west country drifting slowly NNW...Some good t-storm parameters in that area, some increased SB CAPE, the atmosphere is bouyant at the lower levels, and lapse rates are high, aiding convection...Not expecting anything here to the north of Birmingham, but one never knows for sure...

...Just editing my horrific spelling...lol

Edited October 25, 2011 by ajpoolshark