Convective / Storm Discussion - 22nd October onwards 2013

[Guest William Grimsley]

It's quite likely that heavy/thundery showers will move into SW England overnight. Hopefully, one of these will hit, here.

[Cakie]

Looks like a small squall line passing through Brighton just now.

 

hiradarzoomv42.png

Tell me about it, just got caught on the way back from the wine bar after a cheeky Chennin blanc while staying at Grandma Loo's. Completely soaked to the skin, more than on the water rides at legoland today

[Stuart]

Synopsis

Upper trough will migrate northeastwards across the British Isles throughout the forecast period, followed by a second, sharpening upper trough over the Atlantic - the culprit for the explosive development of low pressure 'Christian'. Cool mid-levels overspreading warm SSTs will promote another day of convection, particularly near windward coasts.

 

Discussion

... EAST ANGLIA, SE ENGLAND ...Occlusion (quasi-cold front) will continue to clear eastwards out to the North Sea between 00z-04z, with further line segment elements along the front as a result of strong DLS near the rear edge (40-60kts). Given low LCLs and slight veering of surface winds, there is a low risk of a short-lived tornado.... SW ENGLAND, SW WALES ...Main risk period is 00z-11z as a couple of shortwaves cross the area, associated with lines of deep convection. A few hundred J/kg and ELTs down to -40C suggests some lightning is possible with the strongest cells, and given 20-40kts DLS, increasing throughout the day as the upper jet approaches, such cells will be organised capable of producing some hail (locally up to 2.0cm in diameter), strong, gusty winds and perhaps a tornado given low LCLs.Showers will be replaced by frontal shield and rain as next low pressure system, 'Christian', approaches from the southwest with strong but largely non-convective-induced winds overnight. ... W SCOTLAND ...Showers and a few thunderstorms will affect the area for much of the forecast period, and with 20-30kts DLS forming bands at times and bringing the risk of local surface flooding. Strong LLS and low LCLs suggests the potential for short-lived waterspouts/tornadoes in any stronger, well-organised cells. Hail up to 1.5cm in diameter is also possible.Showers will affect many other areas through the day, and with strong low-level shear and helicity, some well-organised cells may exhibit some supercellular characteristics

 

http://ukasf.co.uk/storm-forecasts/292

 

[Flipflop]

Sorry not had time to read or catch up with current watches but just had a quick look at the radar and seen this...looks electrical in nature 

 

Will this have the legs to reach the East Coast! if so when... Cheers.

 

Back to Megastormendoftheworld if not.

 

[tara303]

here in West Limerick the sky is flickering to the east, the rain is hammering down on the veluxi and the wind is now beginning to howl through the trees.  Candles at the ready here for the inevitable!

[A.J]

just had quite a well defined squall line pass through in the past 30 mins giving very heavy rainfall and gusts well in excess of 40mph...certainly pretty lively and more to come overnight as further troughs are forecasted to pass through

[Nick F]

Storm & Convective ForecastIssued 2013-10-26 22:58:58Valid: 27/10/2013 0000z to 28/10/2013 0000zTHERE IS A RISK OF THUNDERSTORMS FORECASTSynopsisUpper trough moves through from the west over next 24 hrs, with surface cyclone to the NW of Britain and another deepening secondary low further southwest. An active cold front moves east across the UK tonight, reaching the east coast by 06z. An unstable rPm airmass follows in wake of the cold front.... WHOLE OF THE UK AND IRELAND ...Cold front, currently over Ireland, will continue east across the UK tonight reaching the east coast around 6am Sunday. Deep convection with thunderstorms have occured across Ireland this evening near/along this front, with a risk of further thunderstorms tonight with passage of the front over mainland UK - bringing hail, gusty winds and heavy rainfall with a risk of localised flooding. Once this area of showers/storms near/along cold front clears the east of England during Sunday morning, further deep convection, with risk of thunderstorms, will spread in from the west across northern, central and western areas through the day - as upper trough overspreads from the west.Any thunderstorms that occur will be in a highly sheared environment characterised by deep layer shear of 30-60 knts and low-level shear of up to 35-40 knts across the UK and Ireland - which will be sufficient for storm organisation, with a risk of strong convective wind gusts and also isolated tornadoes can't be ruled out - the latter most likely near coastal areas where boundary layer will be most unstable given seasonally warm SSTs.Any potential severe weather events look to be rather isolated and difficult to pinpoint, so have refrained from issuing a SLIGHT risk to cover all the UK, but this doesn't mean a SLIGHT risk of severe weather will not materialise.Issued by Nick Finnis

Edited October 26, 2013 by Nick F

[I Cumbria Marra I]

just had a very heavy 5 minute shower and iv heard 3 very distant rumbles with my window slightly open.

[Cheshire Freeze]

That's some squall just coming into Wales. I'd imagine there's some T&L associated with that lot, so some people could be getting woken up shortly.

[I Cumbria Marra I]

OMG its getting closer, just seen a flash.

and another! best thunderstorm all year this looool

[Cheshire Freeze]

OMG its getting closer, just seen a flash.

 

Part of me wants to stay up and wait for that lot out west to get here. However I have work tomorrow so sleep is a must really. Could be my first thunder and lightning of the year though.......torn! Why do these things have to happen at such silly times?

Edited October 27, 2013 by CreweCold

[I Cumbria Marra I]

Part of me wants to stay up and wait for that lot out west to get here. However I have work tomorrow so sleep is a must really. Could be my first thunder and lightning of the year though.......torn! Why do these things have to happen at such silly times?

that sucks, we always seem to get more thunderstorms in autumn than summer these days

[I Cumbria Marra I]

Epic squall approaching Wales.... 

[Cheshire Freeze]

I wonder if there's a tornado risk associated with that lot about to hit Wales?

[swales]

Yep, just had hell of a blinding flash as I was looking out of the window here in West Wales. Exciting.

[ChezWeather]

Wow that is a really nice looking squall line! Hope it makes it inland and to here! 

[paul m]

Well i'm sitting tight, considering lightning is being reported, thanks Shaun

Case of anything could happen now, all moving along pretty sharpish mind.

Bit quieter in here too lol

[Cheshire Freeze]

Good question indeed, I believe estofex also issued a level 1 for parts of the Uk yesterday. Should be with us in an hour or two, wind already picking up, gulp... This second belt is certainly looking a fair bit livelier than yesterday's half hour soaker...

Yes, a high end level one for severe wind gusts associated with this feature.

[Panayiotis]

Should be over me in the next hour, and I will stay awake for this one me thinks.

Edited October 27, 2013 by Panayiotis

[Raidan]

Quite windy here but have more interest in weather there will be anything thundery but struggling to stay awake and wondering if its worth trying to up with the possibility nothing will happen

[georgiedre]

Wow 2 thunderstorms in 2 hours!!! And the rain was immense!

[paul m]

Meteo radar gone a bit iffy so cannot see where it currently is

[paul m]

Wind picking up here

[ChezWeather]

Debating on whether to stay up or not! 

Edited October 27, 2013 by ChezzieStorms

[paul m]

Im going to give it an hour then get some sleep ready for the rollercoaster potential storm forum lol