Convective Storm/Discussion thread - 11/06/16 onwards

[BrickFielder]

 Bit of a Spanish plume type scenario Wednesday into Thursday. Current charts would suggest elevated storms coming in over Wednesday night which might become boundary layer active as they move out over the north sea. This is then followed by further storms become active from mid morning onwards, possibly with an MCS scenario.

Typically these types of events do tend to move eastwards as we move closer to the event, but there is no guarantee. Dewpoint temperatures at 20 C seem a bit high for the UK and 18 C is usually where they top out. So its way to early to predict at this point.

[B87]

A bit late, but here are some pictures from Friday afternoon around 6pm, and some more from a train just after 7pm, as the storm headed south.  Also took a screen shot of the radar as it looked a bit suspicious..

[Summer Sun]

Day 2 Convective Outlook

VALID 06:00 UTC Mon 20 Jun 2016 - 05:59 UTC Tue 21 Jun 2016

ISSUED 16:28 UTC Sun 19 Jun 2016

ISSUED BY: Dan

Sharpening upper trough aligned Poland - Tunisia will encourage yet another day of severe thunderstorms across eastern Europe and the northern Balkans on Monday, with all severe hazards possible (large hail, severe wind gusts and tornadoes). Meanwhile, over the British Isles comparatively benign conditions are expected beneath a fairly strong jet streak aloft and a fairly complex frontal system crossing England and Wales - likely to lead to a split cold front regime with a well-marked shallow moist zone (SMZ) behind the main area of frontal precipitation.

Surface dewpoints remain at 14-15C into the afternoon (after morning rain), and although extensive low cloud seems likely in the SMZ, any breaks that develop to allow some diurnal heating, coupled with strong DLS and some areas of low-level convergence, perhaps along the trailing cold frontal boundary, may allow some elements of convection to occur in linear fashion parallel to the flow. Hence a few lines of showers may develop, although the depth of convection will be limited by very dry profiles above 600mb - and so lightning potential remains quite low, hence the broad LOW threat level issued. In fact, it is plausible that there may be no lightning at all, just a few heavy showers. Such events typically produce rather turbulent-looking low cloud bases.

http://www.convectiveweather.co.uk/forecast.php?date=2016-06-20

[Nick F]

Quick look at potential next week, as at work ...

Low risk that a few thundery showers could develop once the rain clears across southern areas tomorrow afternoon. 

Then, 12z GFS sweeps some elevated CAPE across the S/SE of England early Wednesday, then some surface-based CAPE Weds afternoon across eastern parts, so be interesting if something can develop out of that:

Weds 03z

Weds 12z

12z GFS just has a MCS Kent Clipper Wednesday night / Thurs morning ... seems to be the way it always goes I'm afraid, but still time for it to head NE further west. 00z ECM moved an MCS over the SE on Wednesday night ... so be interesting to see what it comes up with on the 12z.

Edited June 19, 2016 by Nick F

[B87]

Were there any reports of funnel clouds over Surrey or Sussex on Friday night, in relation to the pictures I posted above? It seemed like there was something trying to lower from the cloud base, though it could have been scud. The radar makes it look like there was rotation, but the base of the cloud was always behind buildings so I couldn't tell for sure?

I'm surprised nobody else managed to get pictures or mentioned that particular storm?

Edited June 19, 2016 by B87

[Harry]

GFS starting to get a real eastward wriggle on at the moment - rather disappointed but still scope for some change between now and mid week

[East_England_Stormchaser91]

30 minutes ago, Harry said:

GFS starting to get a real eastward wriggle on at the moment - rather disappointed but still scope for some change between now and mid week

Marginal improvements again since this morning, with a very very slight shift west. 

This is such a knife edge at the moment. Last year we did see miracles however at around this time out, it got corrected back west enough to get the majority in the game! I hope it can happen this time too. A very close eye will be kept by me on this over the next couple of days. 

I was up for binning it completely this morning, but I have a glimmer of hope, especially for those in the likes of Kent  

Edited June 19, 2016 by East_England_Stormchaser91

[Severe Blizzard]

Let's hope West Surrey & East Hampshire get a chance this time - this set up has brought nothing but disappointment last year and this year - The 'bust' repetition is getting very tiresome. Not much fun when the home-grown storms fail as well as over the last 12 days or so. Suffering Storm Deprivation Syndrome real bad now and will not be happy if Thursday is another let-down to add to the 32 others this year to date in Guildford.

[stainesbloke]

Plenty of Summer left to get some nice storms, though I must agree with others in saying how very tiresome it is to constantly miss out on anything interesting electrically whilst the near continent gets pounded yet again. Definitely a huge shift in our climate in that regard since the new century began, especially here in the SE that saw decent storms every summer. I attach a newspaper clipping from August 1981 when true daytime darkness was experienced here from storms that reached over 50,000 feet high - yes that's about 8 miles!! 3 people were struck by lightning at Heathrow. I remember it well and it scared the crap out of me but got me fascinated by storms. The photo is from midday...unbelievable really. It happened again in the 80's a few times, the last time here in 1991. The 1981 storm occurred after a few hot (30C) days but in a run of generally crap summers like we are in.

Edited June 20, 2016 by stainesbloke

[Bolt from the Blue]

Weds & Thurs looking good for South Central and Eastern England, just take a look at those CAPE values on the near continent!

 

[Sprites]

20 minutes ago, AIRMET said:

Weds & Thurs looking good for South Central and Eastern England, just take a look at those CAPE values on the near continent!

 

 

[Sprites]

1 hour ago, stainesbloke said:

Plenty of Summer left to get some nice storms, though I must agree with others in saying how very tiresome it is to constantly miss out on anything interesting electrically whilst the near continent gets pounded yet again. Definitely a huge shift in our climate in that regard since the new century began, especially here in the SE that saw decent storms every summer. I attach a newspaper clipping from August 1981 when true daytime darkness was experienced here from storms that reached over 50,000 feet high - yes that's about 8 miles!! 3 people were struck by lightning at Heathrow. I remember it well and it scared the crap out of me but got me fascinated by storms. The photo is from midday...unbelievable really. It happened again in the 80's a few times, the last time here in 1991. The 1981 storm occurred after a few hot (30C) days but in a run of generally crap summers like we are in.

 

[Sprites]

Plenty of Summer left to get some nice storms, though I must agree with others in saying how very tiresome it is to constantly miss out on anything interesting electrically whilst the near continent gets pounded yet again. Definitely a huge shift in our climate in that regard since the new century began, especially here in the SE that saw decent storms every summer. I attach a newspaper clipping from August 1981 when true daytime darkness was experienced here from storms that reached over 50,000 feet high - yes that's about 8 miles!! 3 people were struck by lightning at Heathrow. I remember it well and it scared the crap out of me but got me fascinated by storms. The photo is from midday...unbelievable really. It happened again in the 80's a few times, the last time here in 1991. The 1981 storm occurred after a few hot (30C) days but in a run of generally crap summers like we are in.

 

I remember seeing the top of this storm above the houses from my garden. 50,000 ft is about 9.5 miles, not something you will see very often unless in the US. May be once in a lifetime storm for the UK.

Edited June 20, 2016 by Sprites

[stainesbloke]

2 minutes ago, Sprites said:

I remember seeing the top of this storm above the houses from my garden. 50,000 ft is about 9.5 miles, not something you will see very often unless in the US. May be once in a lifetime storm for the UK.

Certainly a rare occurrence in the UK; it was actually terrifying! The darkness was intense and we had flash floods, that lifted a bit then the most amazing lightning display started for a couple of hours. I've experienced daytime darkness 3 times in the UK from storms where all the streetlights came on. Hasn't happened since the early 90's.

[Azazel]

21 minutes ago, stainesbloke said:

Certainly a rare occurrence in the UK; it was actually terrifying! The darkness was intense and we had flash floods, that lifted a bit then the most amazing lightning display started for a couple of hours. I've experienced daytime darkness 3 times in the UK from storms where all the streetlights came on. Hasn't happened since the early 90's.

I've only seen it once. Sometime in May 1999. Pretty sure it was an MCS but you know, we don't get stuff like that anymore.

[Harry]

31 minutes ago, Azazel said:

I've only seen it once. Sometime in May 1999. Pretty sure it was an MCS but you know, we don't get stuff like that anymore.

They were quite common in the 90s - almost annually if I recall correctly.

Could be very close call Wednesday evening.

[weather09]

Still while out and likely to be considerable change ahead, but adding to Nick's summary above, ECM/GFS still going for thunderstorms across far E/SE quarter from Weds eve and into Thurs when we see moisture-rich low-level airmass of high WBPTs advect over the region, destabilising with forcing with approach of upper trough/forcing aloft. Given likelihood of strong mid-upper winds with SW jet aloft, generating strong deep layer shear and large scale forcing, and drier mid-level air atop moist low-level airmass, creating a very unstable environment, strong thunderstorms and general MCS storm mode looks likely for aformentioned regions if current outputs verify, bringing hazards such a frequent CG lightning, potentially large hail, and strong downdraft winds.  

With rich moisture and large scale forcing, risk not dependent on diurnal heating, however daytime surface-based storms (which is most possible Thurs on current outputs) always bring increased risk of severe convective weather as they draw greater energy from good insolation and strong heating of boundary layer. 

Edited June 20, 2016 by weather09

[MP-R]

45 minutes ago, Azazel said:

I've only seen it once. Sometime in May 1999. Pretty sure it was an MCS but you know, we don't get stuff like that anymore.

Yes! 29th May 1999 brought daytime darkness here from a huge storm system that crossed over during the afternoon. Impressive storm that came only 36 hours after an MCS overnight 27th/28th May. Coupled with storms that came on the 02nd June, that was a brilliant stormy period!

[Azazel]

Just now, MP-R said:

Yes! 29th May 1999 brought daytime darkness here from a huge storm system that crossed over during the afternoon. Impressive storm that came only 36 hours after an MCS overnight 27th/28th May. Coupled with storms that came on the 02nd June, that was a brilliant stormy period!

thats the one! the sky went dark green here and all the streetlights came on. Some of the cloud motion was incredible too. Remember it coming up from the south-west so yes definitely the same one.

[MP-R]

26 minutes ago, Azazel said:

thats the one! the sky went dark green here and all the streetlights came on. Some of the cloud motion was incredible too. Remember it coming up from the south-west so yes definitely the same one.

It was terrific. I had only recently swapped my fear of storms for sheer interest, so I loved every minute of it. Storms like that have been fewer and further between in recent times.

[Vestan]

I always enjoy these days, with the expectation of something very big around the corner, but at the same time knowing I will probably be disappointed when it all ends up to my east or a Kent clipper.  Although I've had a couple of rumbles around me, I'm still waiting for one right overhead, but there is a long way to go in the summer and I always thought July offered the biggest opportunities to experience something.

Will be reading the thread in anticipation over the next couple of days

Edited June 20, 2016 by Vestan

[Jimmyh]

3 hours ago, stainesbloke said:

Plenty of Summer left to get some nice storms, though I must agree with others in saying how very tiresome it is to constantly miss out on anything interesting electrically whilst the near continent gets pounded yet again. Definitely a huge shift in our climate in that regard since the new century began, especially here in the SE that saw decent storms every summer. I attach a newspaper clipping from August 1981 when true daytime darkness was experienced here from storms that reached over 50,000 feet high - yes that's about 8 miles!! 3 people were struck by lightning at Heathrow. I remember it well and it scared the crap out of me but got me fascinated by storms. The photo is from midday...unbelievable really. It happened again in the 80's a few times, the last time here in 1991. The 1981 storm occurred after a few hot (30C) days but in a run of generally crap summers like we are in.

I will still never forget that storm. it was unbelievable. water came cascading down the walls at home, that's when my dad realised there was a whole in the roof. cost us our summer holiday lol. never ever forget it

[Windblade]

2 hours ago, Azazel said:

I've only seen it once. Sometime in May 1999. Pretty sure it was an MCS but you know, we don't get stuff like that anymore.

That's the thing though, why don't we get this kind of stuff anymore? I remember night time storms that were still rumbling and flashing away at 8-9am the next day. Haven't had anything like that in years, but cannot understand why?

[Farmer Dave]

I'm a fruit grower in north Kent and I can remember some mega storms over the years but not recently. We did get hail damage on our fruit crops last year though from two storms - one storm had hail the size of a 50p. The irony is I love a good storm but my crops can be ruined in seconds!

[Speedway Slider]

4 hours ago, stainesbloke said:

Plenty of Summer left to get some nice storms, though I must agree with others in saying how very tiresome it is to constantly miss out on anything interesting electrically whilst the near continent gets pounded yet again. Definitely a huge shift in our climate in that regard since the new century began, especially here in the SE that saw decent storms every summer. I attach a newspaper clipping from August 1981 when true daytime darkness was experienced here from storms that reached over 50,000 feet high - yes that's about 8 miles!! 3 people were struck by lightning at Heathrow. I remember it well and it scared the crap out of me but got me fascinated by storms. The photo is from midday...unbelievable really. It happened again in the 80's a few times, the last time here in 1991. The 1981 storm occurred after a few hot (30C) days but in a run of generally crap summers like we are in.

Was this a Friday?