Uk Convective General Discussion & Forecasts, 27th June 2012>

[PolarWarsaw]

Still nothing here. No rain, the odd distant rumble. Reckon the cell to the SE of this one has our name on it aj?

[Will Padz]

TORRO TORNADO WATCH 2012/004

A TORNADO WATCH has been issued at 0740GMT on Thursday 28th June 2012

Valid from/until: 0740 - 2000GMT on Thursday 28th June 2012, for the following regions of the United Kingdom & Eire:

Parts of (see map)

Wales

Midlands

E Anglia

N England

Southern and central Scotland

THREATS

Tornadoes; hail to 40mm diameter; wind gusts to 65mph; Frequent CG lightning

SYNOPSIS

Plume of high theta-w air has advected across much of Britain overnight with a large upper trough approaching from the west. At the surface, a cold front will move north-eastwards through the day.

Diffluent upper flow ahead of the trough is bringing forcing for ascent across portions of Wales already, and a number of thunderstorms have developed. At this stage they are likely marginally elevated above a coolish boundary layer, but strong cloud-layer shear suggests large hail to 20-30mm is possible with this early activity, with elevated supercells possible, with clusters of storms are likely. Gusty winds also possible.

This activity is expected to continue to move NNE and NE through this morning. Although there is a fair amount of mid-level cloud associated with the widespread large-scale ascent ahead of the trough, enough diurnal heating of the boundary layer is expected to allow storms to become surface based as the cluster of storms moves through the Midlands into N England, and later, Scotland. With 30-40 knots of deep layer shear, well-organised multicells and embedded supercell structures are likely. 20-30mm diameter hail and gusts to 60mph are possible. In addition, isolated tornadoes are possible.

In the wake of this activity, and across the more south-eastern parts of the WATCH area, further thunderstorms are expected to develop and the move north-east, although these will be more isolated with south-eastern extent. Modified ascents for afternoon temperatures suggest around 1200-1800 J/Kg of SBCAPE. WIth 0-6km shear remaining around 40 knots, and perhaps increasing a little, well-organised multicells and isolated supercells seem possible. With 0-1km SREH of ~150 J/Kg and fairly low LCLS, a few tornadoes may develop with this activity. Indeed, should an isolated supercell develop in an area with decent surface heating, a strong tornado cannot be ruled out. Hail to 40mm or so and wind gusts to 65mph possible with supercells too; otherwise, 20-30mm hail and 55mph gusts. If this activity can develop into northern parts of England too, it may tend more towards a squall line, with an associated wind threat.

The activity will end from the south-west through the afternoon and evening as the cold front moves in.

Forecaster: RPK

[Kain]

Thunder is fading now as is the lightning waiting for number 2 to come in behind! Kitchen wreaked though

[Cloudwatcher]

This thing seriously needs to take a left turn! Do storms have SatNav? Tell it to plug in Crewe (for my storm starved Cheshire East friend there) and then Warrington .

Very sunny here right now.

Hopefully we will both see a bit of action today! Can't see it doing a left though...

[Coast]

Lordy, you'd pay good money all year 'round to get a detector screenshot like this!!!!!

[A.J]

The outflow from this 'MCS-in-the-making' should be the trigger for numerous storms developing through the midlands in the next few hours....**strewth, what a lightning strike just then!!**

[OddSpot]

Looks like I'm in a good spot!

Hope so. Just rang me mum in Bolsover that a storm could be about to arrive in the next hour after checking out Sat24 and Rain Today.

[AWD]

Lordy, you'd pay good money all year 'round to get a detector screenshot like this!!!!!

How close could I be!!

[Deluxe]

Shout out to all my homies in Sheffield/Chesterfield and in general South Yorks and peak District area. Hope you see an epic storm today!

It's been a terrific morning reading this forum so far - the lightning detector image is stunning, and it should only get better

[Phelpsy]

Can hear faint distant rumbles, twitter reports of thunder in the forest of dean and some constant lightning and thunder in Worcester

[neil_b]

Thunder is fading now as is the lightning waiting for number 2 to come in behind! Kitchen wreaked though

And to think I'm out of town and missing this - how is it comparing to May 9th last year??

I'm actually sat in Leek, Staffs so what are my chances of seeing some of this?

[Lynxus]

Gloucester shield in full force!

[I Cumbria Marra I]

The storm is brewing!! just heard thunder!

[SalopWatcher]

Its almost merged into one big area of storms now, with new cells east of Malvern over Worcester, further back west over Leominster, and still new ones heading up from the breeding grounds of Newport and Chepstow. The whole thing keeps growing and growing anywhere west of a line from Newport to Stafford should start getting ready.

[Kain]

And to think I'm out of town and missing this - how is it comparing to May 9th last year??

I'm actually sat in Leek, Staffs so what are my chances of seeing some of this?

Best storm ive seen in 10 years Neil, May 9th looks abit pants compared it it. at one point constant lightning and thunder continusly for around 10 mins. I have taken a vid so

[Chris K]

Noooooooo If i wasn't working this morning I could be watching lightning from where I live across the Severn Estuary.

Dammit....I guess bristol is a no-go area for t-storms for today still?

Looks amazing just a shame it's so tantalisingly close but the direction everything is going isn't good for me.

[Jane Louise]

Nothing happened here as usual lol. I should of known better the storms from South wales were heading North but they came so close to me on the NW extra radar ! hoping something later may head my way .

[tinybill]

watching the radar Birmingham is in the firing line

[I remember Atlantic 252]

first flash seen, few rumbles as well, just moderate rain

[JinxTheCat]

Just starting up here

[Norfolk Sheep]

ooh looks like I might get some thundery rain in an hour or so *faints*

[Kain]

Lighting getting frequent again now and booms are getting louder...round 2

[c_jephcott]

Very distant rumble in Sutton Coldfield. Could have been bin men, but getting darker by the minute here. Something is happening shortly, be it rain or more!

Edited June 28, 2012 by c_jephcott

[A.J]

ok....absokutely drenched...got about 15 mins of video footage, need to recharge the camera again......in terms of lightning flashes, this blows MAY 9th last year out of the water 1-3 flashes per second from all parts of the sky...It's all high based though meaning it's mainly 'sheet' lightning thus I don't know how well it's going to come out on video...I'll upload all footage this evening

[Cheshire Freeze]

I'd give my right arm to be under that lot right now. Why oh why couldn't it have pushed N 50 miles further west?

It's funny how the stuff out in the Irish Sea has pushed north, missing me....and the stuff over the Midlands drifted east....missing me. Aaaargghhh!

Edited June 28, 2012 by CreweCold