Convective/Storm Discussion Thread - 1st August onwards

[Chris.R]

 Maybe some potential for up here tomorrow morning and then further to the east in the afternoon. 

[Windblade]

So, last night after so much potential turned out to be a bust. Still, we had some lovely cooling showers and I did see a storm on the Le Havre surf cam which was pretty powerful with flashes every 10 seconds or so. Couldn't post the link as was on xbox, but for future reference just go to google and type in Le Havre live webcam and its the surf cam that comes up. Nice and cool today as forecast. Glad that awful heat and humidity has buggered off!  Hoping there is still some potential left for this week as we are now into the last part of the season, but unsure at this stage?

Edited August 30, 2017 by Windblade

[Flash bang flash bang etc]

1 hour ago, Windblade said:

So, last night after so much potential turned out to be a bust. Still, we had some lovely cooling showers and I did see a storm on the Le Havre surf cam which was pretty powerful with flashes every 10 seconds or so. Couldn't post the link as was on xbox, but for future reference just go to google and type in Le Havre live webcam and its the surf cam that comes up. Nice and cool today as forecast. Glad that awful heat and humidity has buggered off!  Hoping there is still some potential left for this week as we are now into the last part of the season, but unsure at this stage?

Feeling like - unless there's another Indian summer on the cards like, soon - we're done for this year. One big storm and that's 2017 right there.

Truely awful - considering the last 2 months were mostly grey, cool and showery - and looking at the shocking number of failed plumes (in fact I only really consider 2 to have made any impact).

Last night really sums it up. You could draw a line where the lightning stopped and it would have neatly hugged the UK coastline up through Kent. Just 50 miles north or east and it would have been at least visible from our area - but no.

Too much to ask for two thunderstorms this year.

Just putting together dates for a late September holiday and I will certaintly be considering potential for Mediterranean storm possibilities as part of the decision process.

[Windblade]

2 hours ago, Flash bang flash bang etc said:

Feeling like - unless there's another Indian summer on the cards like, soon - we're done for this year. One big storm and that's 2017 right there.

Truely awful - considering the last 2 months were mostly grey, cool and showery - and looking at the shocking number of failed plumes (in fact I only really consider 2 to have made any impact).

Last night really sums it up. You could draw a line where the lightning stopped and it would have neatly hugged the UK coastline up through Kent. Just 50 miles north or east and it would have been at least visible from our area - but no.

Too much to ask for two thunderstorms this year.

Just putting together dates for a late September holiday and I will certaintly be considering potential for Mediterranean storm possibilities as part of the decision process.

I feel for you buddy, although my storm season this year has actually been far better than 2016 (dismal by all accounts). I've witnessed a couple of decent elevated storms (one at night - my best time for a storm), seen a nighttime supercell over london that had constant strobe lightning for over two hours - visible from my house 20 miles away, seen quite a few pulse storms (one or two flashes and rumbles only) had a couple of thunder days/evenings and seen a funnel cloud. The only thing I have yet to see this year is fork lightning (all the stuff I've seen has been IC only). I did miss two really good (apparently) storms right over my house this month so annoyed about that as it would have been two more to add (with the possibility of seeing forks) but we still have september to go which has produced some decent storms in the past so don't give up hope just yet friend. 

Edited August 30, 2017 by Windblade

[Windblade]

Also Flash, netweathers daily article today mentions possible storms tomorrow and also friday night. Might be worth keeping an eye on. 

[Dangerous55019]

Evening everyone. 

We've had some beautiful covectivity going on around here today... And here is an example of this evenings offering. 

Doubtful it'll go bang... But it's still nice to see. 

[Allseasons-Si]

Netweather has upped it's storm risk tomorrow to 52% here on the 12z gfs,now lets have a look at the latest models and i will pick 18z tomorrow

WFF-NMM 2km ppn and sbcape/li

WRF-NMM 0.05 ppn and sbcape/li

APERGE ppn and mucape(had to pick 5pm mucape,no 6pm)

gfs 5pm and 8pm ppn and cape/li

HIRLAM ppn,no cape/li charts on this model

AROME ppn and mucape

so both the WRF models go for something similar whilst the APERGE goes for showers to break out earlier then die away mid to late afternoon,the gfs over egg's it with the ppn lol but not much cape/li values,love the AROME though with the skeletor looking cape chart lol

good luck tomorrow peeps

[Cheshire Freeze]

14 minutes ago, Dangerous55019 said:

Evening everyone. 

We've had some beautiful covectivity going on around here today... And here is an example of this evenings offering. 

Doubtful it'll go bang... But it's still nice to see. 

I think you're being very generous calling that convection. Shallow convection at best.

[Summer Sun]

Day 2 Convective Outlook

VALID 06:00 UTC Thu 31 Aug 2017 - 05:59 UTC Fri 01 Sep 2017

ISSUED 19:50 UTC Wed 30 Aug 2017

ISSUED BY: Dan

Upper trough and associated cold pool / steep lapse rates will drift gradually southeastwards across the British Isles, generating several hundred Jkg^-1 CAPE. Showers will be ongoing over western areas at the beginning of the forecast period, with several high-res models suggesting a cluster of thunderstorms possible over N Wales / NW England and adjacent Irish Sea during the morning, lightning activity then becoming more widespread through the day as showers develop more widely. Late arrival of upper trough means showers may be late to arrive / develop over East Anglia and SE England, and hence linger for quite some time during the evening.

In general, convection a little more limited in depth across southern areas than farther north, hence a better aerial coverage of lightning is more likely over northern England. There may also be an uptick in activity over the English Channel / Channel Islands during the early hours of Friday, hence a low-end SLGT issued here.

 

Hail up to 1.5cm in diameter will be possible with the strongest cells, allowing the the risk of some localised surface water issues given slow storm motion. A few funnel clouds cannot be ruled out.

 

http://www.convectiveweather.co.uk/forecast.php?date=2017-08-31

[Chris.R]

My forecast for coastal Northwest England/NorthEast Wales is as follows. Some intriguing potential in the early hours of ocean effect convection developing as a cold pool moves overhead. GFS is showing up to 1050 j/kg CAPE around in Liverpool bay by 07Z.  Heavy showers quite possible with a decent chance of some lightning activity I would say. This often tends to be an all or nothing type set up though.

After the diurnal minimum (09Z/10Z) it will probably be a fair day with Sonny spells and light showers but heavy perhaps thundery showers beyond 10 miles inland developing through land insolation.  

Edit: Just seen Convective-weather's forecast; sounds like similar thoughts regarding early morning tomorrow from them. 

Edited August 30, 2017 by Chris.R

[Nick F]

Storm & Convective Forecast

Issued 2017-08-30 21:58:02
Valid: Thurs 31 Aug 2017 - 6am to Fri 01 Sept 2017 - 6am

Day 1 Convective / Storm Forecast

Synopsis

Long wave upper trough axis will slide east across the UK during Thursday. A slack cyclonic and unstable westerly flow, veering NWly across the far west, covers the UK, supporting widespread showers and scattered thunderstorms.

... IRELAND, ENGLAND, WALES and S SCOTLAND ...

Upper trough and associated cold mid-levels will create steep lapse rates across much of the UK as it slides eastwards on Thursday ... which will support the development of heavy showers and scattered thunderstorms which, with light winds aloft, will drift slowly eastwards.

Troughs in the flow may focus showers/storms into slow-moving clusters capable of producing localised minor flooding, otherwise weak vertical shear / unidirectional wind profiles should discourage an organised severe risk, though there maybe isolated instances of hail to 1 - 1.5cm given steep lapse rates and potential for strong updrafts with surface heating in late August sunshine. Also, a few funnel clouds, which may even reach the ground as a brief/weak tornado, can't be ruled out - given favourable conditions of several wind convergence zones, light winds aloft and fairly low cloud bases.

Issued by: Nick Finnis

[Thunderstruck]

Sferic near Southampton? Guessing false return, but can anyone in the area confirm? 

Edited August 30, 2017 by Jcweather

[Liam Ellis]

Thunderstorm reported in North Wales Wales. Blitzortung has got a few lightning strikes up there. Gosh, it's been dire down here in Cardiff this year...

[Dangerous55019]

8 hours ago, CreweCold said:

I think you're being very generous calling that convection. Shallow convection at best.

Morning @CreweCold 

Admittedly it wasn't a patch on what I'd seen earlier in the day (which did give quite an impressive power shower), but after the nothingness of weak fluffy convection that we had in the first part of this year, I'm taking this as a positive step in the right direction. 

[Dangerous55019]

Well that was a dramatic and atmospheric drive into work... The dark blue of the dawn skies, lit up with good flashes of forked and sheet lightning. 

[James1979]

21 hours ago, Flash bang flash bang etc said:

Feeling like - unless there's another Indian summer on the cards like, soon - we're done for this year. One big storm and that's 2017 right there.

Truely awful - considering the last 2 months were mostly grey, cool and showery - and looking at the shocking number of failed plumes (in fact I only really consider 2 to have made any impact).

Last night really sums it up. You could draw a line where the lightning stopped and it would have neatly hugged the UK coastline up through Kent. Just 50 miles north or east and it would have been at least visible from our area - but no.

Too much to ask for two thunderstorms this year.

Just putting together dates for a late September holiday and I will certaintly be considering potential for Mediterranean storm possibilities as part of the decision process.

That's what I've done, hoping for a thundery Menorca later in September... which means you guys will have a thundery late September as I'll be away! 

[Frosty hollows]

I'm staying in the Ribble Valley. Woke up to a heavy shower and a clap of thunder.Skies look murky rather than organised though. Rain looks very slow moving

[Another Kent clipper]

I'm currently having a McDonald's breakfast in Clifton, (Salford). I'm ready to drive for some lightning, the action seems to be to the north and messy if the storm is anything to go by.  Any expert suggestions as where to go today?

[Dangerous55019]

Looks like something is starting to get going again just off the coast at Prestatyn.

[karyo]

23 minutes ago, Dangerous55019 said:

Looks like something is starting to get going again just off the coast at Prestatyn.

morning Dangerous,

looking at the radar, it looks like the showers are not moving anywhere. It is still dry here.

[Another Kent clipper]

Ramsbottom.  Wet.

VID_20170831_095158.mp4

[Dangerous55019]

41 minutes ago, karyo said:

morning Dangerous,

looking at the radar, it looks like the showers are not moving anywhere. It is still dry here.

Morning @karyo 

I agree mate... It looks to be stuck out at sea, just off the coast.

[karyo]

Just caught a brief heavy shower here. 

[Another Kent clipper]

Skies of preparation closer to home in ardwick, Manchester

 

 

[karyo]

2 minutes ago, Another Kent clipper said:

Skies of preparation closer to home in ardwick, Manchester

 

 

Did you catch the shower earlier? It was heavy here.