Storm & Convective Discussion - 01/03/15 onwards

[Harry]

Estofex largely as I had expected to be honest...Kent clipper the best realistic chance. Could be quite a painful watch as no doubt an immense blob will charge towards us during the night and veer off over Benelux. Although estofex even doubtful how much oomph it will have in reaching Benelux.

Look forward to seeing experts' views later on...I note SE quarter under a 15%, echoing Dan's views on Convective Weather (formerly UKASF which I only learned yesterday).

[Nick F]

Netweather storm forecast covering the overnight/Tuesday morning period of most interest with the unstable plume pushing north across parts of England and Wales overnight.

 

THERE IS A RISK OF THUNDERSTORMS FORECAST

 

 

Valid: 04/05/2015 1200z to 05/05/2015 1200z

 

Synopsis

During the forecast period upper trough is slow-moving to the west of the UK, with a deep surface low to the west of Ireland slowly sinking south, while a secondary low to the west of Portugal at the base of the upper trough, moves NE across the Bay of Biscay and deepens as it approaches SW UK.

 

... ENGLAND AND WALES ...

 

A plume of warm and moist boundary layer air of sub-tropical origin will spread north across Iberia and France today in a warm sector ahead of deepening low moving NE across the Bay of Biscay. This plume will push north across England and Wales tonight behind a warm front arriving across southern England later this evening. The seasonally high wet-bulb potential temperature of the moist plume (theta-w values of 14C+) advecting north will become modestly unstable overnight as increasingly cold air in the mid-levels spreads NE aloft steepening lapse rates. Also increasingly dry air in the mid to upper levels of the troposphere will spread NE which further help destabilise the plume.

 

Increasingly divergent air aloft as left exit region of strong SWly jet approaches Sern Britain, falling pressure/heights from the SW and cold front moving in from the SW will all create forced ascent of the plume ... which will support mainly elevated convection embedded in rainfall spreading north along fronts and in warm sector ahead of depression moving NNE across western UK early Tuesday.

 

Elevated thunderstorms are possible from this embedded convection spreading north early Tuesday morning, deep layer shear of 40-50knts will allow organisation of storms in multi-cell clusters, with a risk hail, gusty winds and torrential rain leading to localised flooding. Although confidence in coverage of storms overnight into Tuesday morning is low, there appears to be enough low-end potential for severe weather ... mainly risk of strong wind gusts and risk of flooding, with any storms across Sern and Ern England ... where lift will be maximised towards left exit of jet and triple point of fronts moving NE. So have given a marginal risk of severe weather (5-10% risk of damaging wind gusts and flooding) for these areas.

 

These storms will clear NE across England and out into the North Sea during Tuesday morning, as cold front moves NE and introduces cooler and more stable conditions behind it.

 

Issued by Nick Finnis

 

Forecast issued here: http://www.netweather.tv/index.cgi?action=convective;sess=9f43849247ce404d39fd40e19ddacfcf

 

 

[Harry]

Thanks NickF/W09 - I stand corrected with my over-pessimism.

Roll on tonight (and the snooker, of course!!)

Edited May 4, 2015 by Harry

[Thunderbolt_]

Hmm very interesting, especially during the night hours.

[Nick F]

Thanks NickF/W09 - I stand corrected with my over-pessimism.

Roll on tonight (and the snooker, of course!!)

 

Think I'd rather watch the radar than the snooker - as the latter will probably send me into a coma!

[Captain Shortwave]

There is certainly enough from the models to give some hope of something thundery tonight, though there is nothing so far coming from the metoffice/bbc.

Oh well time to enjoy the pleasant day ahead.

[Supacell]

Liking the look of that forecast from Nick. I didn't expect to be even close to a thunderstorm risk zone tonight

[Azazel]

If i remember rightly, the push of rain was progged by the BBC to move up across this area in the evening, rather than the early hours of the morning. Has it been pushed back a little?

[Mapantz]

If i remember rightly, the push of rain was progged by the BBC to move up across this area in the evening, rather than the early hours of the morning. Has it been pushed back a little?

According to them, it starts around 7pm and clears around 1am, here. Although, their track record for forecasting rain from the south has been poor of late, so anything could happen.

[Harry]

There is certainly enough from the models to give some hope of something thundery tonight, though there is nothing so far coming from the metoffice/bbc.

Oh well time to enjoy the pleasant day ahead.

 

If you listen to Carol Kirkwood's online forecast, she does point towards the risk of thunder

 

In my experience, listening to the 'chaps-in-the-know' on here is more reliable than the MetO/BBC when it comes to thundery events.

[Paul Sherman]

I will be deploying tonight right on the East Coast looking for decent Lightning Opportunities, Early Spring Elevated Storms are always some of the best for CG Lightning around the SE Of England.

 

Hoping to share some of what I get tonight on here tomorrow and hopefully its not a damp squib of frontal rains with embedded rumbles and something a little more lively

[A.J]

I'm on the western flank of the 'warning zone' for severe weather, and will be watching the radar with interest this evening!

[Raidan]

Having read the forecasts I'm lead to believe that the south west has a chance of storms tonight.would be good to have a proper storm just hope that if we do get anything it's not to late in the night as have work in the morning.

[Harry]

I will be deploying tonight right on the East Coast looking for decent Lightning Opportunities, Early Spring Elevated Storms are always some of the best for CG Lightning around the SE Of England.

 

Hoping to share some of what I get tonight on here tomorrow and hopefully its not a damp squib of frontal rains with embedded rumbles and something a little more lively

 

Good luck Paul!!

 

While I think of it, is there a thread anywhere which lists good video cameras for recording thunderstorms (day or night)...had some amazing storms over the last couple of years which stills didn't do justice.

Think I'd rather watch the radar than the snooker - as the latter will probably send me into a coma!

 

Nick, if there's storms the snooker wont get much of a look in I can assure you

[NO LONGER POSTING]

Paul,

This is of proper interest!!

Early morning though :/

[Mapantz]

At least we have something interesting for a wider area, though I suspect the SE quadrant will be the place to be for thundery activity?! The WRF shows convective precip clipping Kent and East Sussex.

Plenty of rain to come though..

I'll have a nice Southerly view from the pub tonight, couldn't be better timing! Fingers crossed.

[Noahjoe]

I'm in a good location if anything does come up from the south but from what i remember last year we had this scenario at least 3 times and every time we just got a lot of rain overnight while the supercellular storms would continue trundling down eastwards along the northern Eueopean coast rather than crossing the channel...is there anything different about tonight?

[Noahjoe]

Paul,

This is of proper interest!!

Early morning though :/

Screenshot_2015-05-04-10-08-38.png

This would be amazing! A nice pre-work treat

[Flash bang flash bang etc]

Got to go to work tomo but I'll be out and about and I'll take a pillow with me in case it's a late one :-D!

Edited May 4, 2015 by Flash bang flash bang etc

[Harry]

0100 and 0700 on the UKMO rainfall projections look interesting.

[Paul Sherman]

Surrey & Harry

 

Yh the Invent looks interesting from what follows the initial Cluster but with it getting light at 415am now hoping the early stuff delivers for Camera effective lightning, not to say that at Dawn you cant reel something off with an F16- F22 Setting but obviously harder than when light.

 

Good luck to all for the first real Plume Risk of the Season!

[NO LONGER POSTING]

Someone is going to get lucky tonight I feel, just could be to far east.

Time will tell, radar watching time haha!!

[William Grimsley]

I think I'm too far west here for thundery activity but who knows? Even so, quite a lot of rain to fall tonight. I haven't seen this amount of rain forecast to fall for over a month!

[A.J]

the current state of play (image © sat24

 

Things brewing to the SW over Biscay into western France

 

[Lauren]

Hi William,

I was wondering if I'd see you back as storm season approaches