Convective Storm/Discussion thread - 16/07/16 onwards

[Convective]

Any chance of another plume, mother nature? Thanks in advance... 

[Gordon Webb]

Met Office has cancelled all Warnings with the exception of SW England

[Darren Bown]

2 minutes ago, Gordon Webb said:

Met Office has cancelled all Warnings with the exception of SW England

At the moment, only NW England have any showers of any potency at the moment.

[Carl46Wrexham]

Pretty intense non electrified shower at the moment. Had one earlier in the day which quickly brought about surface water flooding.

[Harsh Climate]

Looking at where the bulk of showers are devloping at the moment, I would think the warning should be for north west england and parts of yorkshire.

[Dangerous55019]

We had a very heavy shower with thundery rain here about half an hour ago... But I've just seen this sky over towards the west. 
Sadly I doubt it'll be electrical though 

[Dangerous55019]

24 minutes ago, Darren Bown said:

At the moment, only NW England have any showers of any potency at the moment.

 

22 minutes ago, Carl46Wrexham said:

Pretty intense non electrified shower at the moment. Had one earlier in the day which quickly brought about surface water flooding.

I've just been driving through one of them... Really quite potent!! 

[I remember Atlantic 252]

anyone just west of Stafford? seems very heavy shower just missed me, maybe over gnosall area, tracking NE

[IanR]

a very warm and humid feeling week here, peaking on tuesday, enduring all that stickiness, hoping to get a storm at some point

 

but just one pathetic rumble heard on wednesday morning, no lightning seen, 

tuesday had so much potential  , but the timings where wrong as usual, imagine if that cap had lifted during the late evening when it was still 29c at 10.00pm , instead of wedeneday morning when the air had cooled, could have been widespread activity over the north west,  instead of just over the extreme western edges   bitterly dissapointed , the wait goes on 

 

Edited July 22, 2016 by IanR

[Weather-history]

Showers just missed here

 

[Harry]

So, the CZ threat ended in a bust (such is to be expected with such unpredictable aspects of our weather). It is nevertheless very warm and humid this evening, which assuming skies remain largely clear tomorrow will easily allow temperatures to skip close to 30C...yay!

[Allseasons-Si]

Can i have one of these please before the summers out

 

 

[Summer Sun]

Day 2 Convective Outlook

VALID 06:00 UTC Sun 24 Jul 2016 - 05:59 UTC Mon 25 Jul 2016

ISSUED 18:45 UTC Sat 23 Jul 2016

ISSUED BY: Dan

A complex frontal system will spill northeastwards across the British Isles on Sunday, beneath an upper trough. A messy mix of dynamic and convective precipitation is expected with marginal instability, and hence the broad LOW threat level issued - although it is quite likely that many areas will be void of lightning.

The environment may be slightly more conducive for lightning within a narrow window of a few hours on Sunday afternoon over Northern Ireland in the immediate post-frontal airmass. Dewpoints in the mid teens Celsius combined with surface heating should yield 200-400 Jkg-1 MLCAPE, with the potential for a few scattered showers, perhaps a thunderstorm, to develop. 30-40kts DLS should allow some cell organisation to occur, with perhaps some small hail from the strongest cells. Have issued a low-end SLGT to highlight this area better.

http://www.convectiveweather.co.uk/forecast.php?date=2016-07-24

[Dangerous55019]

13 minutes ago, Summer Sun said:

Day 2 Convective Outlook

VALID 06:00 UTC Sun 24 Jul 2016 - 05:59 UTC Mon 25 Jul 2016

ISSUED 18:45 UTC Sat 23 Jul 2016

ISSUED BY: Dan

A complex frontal system will spill northeastwards across the British Isles on Sunday, beneath an upper trough. A messy mix of dynamic and convective precipitation is expected with marginal instability, and hence the broad LOW threat level issued - although it is quite likely that many areas will be void of lightning.

The environment may be slightly more conducive for lightning within a narrow window of a few hours on Sunday afternoon over Northern Ireland in the immediate post-frontal airmass. Dewpoints in the mid teens Celsius combined with surface heating should yield 200-400 Jkg-1 MLCAPE, with the potential for a few scattered showers, perhaps a thunderstorm, to develop. 30-40kts DLS should allow some cell organisation to occur, with perhaps some small hail from the strongest cells. Have issued a low-end SLGT to highlight this area better.

http://www.convectiveweather.co.uk/forecast.php?date=2016-07-24

Well, being as Tuesday (just gone) gave us 2600+ Jkg of MLCAPE, along with a lifted index of -8 to -9 (according to what was forecast anyway) and all it gave this area was one poxy clap of thunder, I'll take whats forecast... It can't do any worse. Lol 

[Dangerous55019]

On 22/07/2016 at 21:16, IanR said:

a very warm and humid feeling week here, peaking on tuesday, enduring all that stickiness, hoping to get a storm at some point

 

but just one pathetic rumble heard on wednesday morning, no lightning seen, 

tuesday had so much potential  , but the timings where wrong as usual, imagine if that cap had lifted during the late evening when it was still 29c at 10.00pm , instead of wedeneday morning when the air had cooled, could have been widespread activity over the north west,  instead of just over the extreme western edges   bitterly dissapointed , the wait goes on 

 

Morning IanR 
Sadly it was the same here... So much potential... Such a  ... But I shouldn't complaint, as June was quite thundery around here 
But having said that, I've seen many days where the MLCAPE figures are almost nil and quite a decent storm has seemingly popped up out of nowhere.
So keep the faith, hopefully something good storm wise will come soon 

[Stuart]

Day 1 Convective Outlook

VALID 06:00 UTC Sun 24 Jul 2016 - 05:59 UTC Mon 25 Jul 2016

ISSUED 13:09 UTC Sun 24 Jul 2016

ISSUED BY: Dan

UPDATE 13:09 UTC N & E Scotland upgraded to a low-end SLGT for the potential for embedded lightning activity to develop through the evening / overnight hours as the approaching upper trough causes mid-level lapse rates to steepen. It is quite likely many areas within the SLGT will remain void of lightning, but there is increasing potential at least for lightning over this area later today. The placement of this SLGT is subject to subtle E-W shifts given some uncertainty over the exact track of the developing low this evening

 

UPDATE 11:56 UTC No changes to the map on this update, although the (already marginal) SLGT is being considered for removal from Northern Ireland. At the same time, parts of NE Scotland may require an upgrade for the evening hours to a SLGT - trends will be monitored

 

A complex frontal system will spill northeastwards across the British Isles on Sunday, beneath an upper trough. A messy mix of dynamic and convective precipitation is expected with marginal instability, and hence the broad LOW threat level issued - although it is quite likely that many areas will be void of lightning.

 

The environment may be slightly more conducive for lightning within a narrow window of a few hours on Sunday afternoon over Northern Ireland in the immediate post-frontal airmass. Dewpoints in the mid teens Celsius combined with surface heating should yield 200-400 Jkg-1 MLCAPE, with the potential for a few scattered showers, perhaps a thunderstorm, to develop. 30-40kts DLS should allow some cell organisation to occur, with perhaps some small hail from the strongest cells. Have issued a low-end SLGT to highlight this area better.

 

http://www.convectiveweather.co.uk/forecast.php?date=2016-07-24

[Summer Sun]

Day 2 Convective Outlook

VALID 06:00 UTC Mon 25 Jul 2016 - 05:59 UTC Tue 26 Jul 2016

ISSUED 11:54 UTC Sun 24 Jul 2016

ISSUED BY: Dan

Broad upper low sits across the Atlantic, south of Iceland, with various upper troughs rotating around the main parent centre. Despite cool air being present aloft on Monday, the steepest lapse rates will have passed through Scotland overnight, and therefore not phasing favourably with diurnal heating on Monday daytime. Nonetheless, numerous showers are expected across the LOW threat area, but with a relatively low risk of lightning given marginal instability - perhaps lightning most likely (if any at all) across E / NE Scotland.

http://www.convectiveweather.co.uk/forecast.php?date=2016-07-25

[Richard Taylor]

sferics have been showing up in Aberdeenshire in the last hour or so. 

Edited July 24, 2016 by Richard Taylor

[doctormog]

12 minutes ago, Richard Taylor said:

sferics have been showing up in Aberdeenshire in the last hour or so. 

Looks like passing to the west of here (not that you'd spot anything through the mist anyway!)

[Stormeh]

Video from the storm that passed over the Aviemore area the other night

 

[Windblade]

So, the last few days have been quite strange. Friday that cell just sat smack bang in the middle of central london and didn't do anything at all.I'm extremely suprised it didn't electirfy as the structure, height, and colour of it was all pointing towards it doing something but absolutely nothing came of it. Its like anything slightly east of the centreline just had no convergence at all. Saturday I saw plenty of cells building in my area with very convective skies but they all drifted away to the east leaving absolutely cloudless skies once again for the afternoon which again was very hot, sticky and uncomfortable. Yesterday looked showery (and showers were forecast) and thankfully it was cooler, but not one single drop of rain fell. 

Edited July 25, 2016 by Windblade

[Nick F]

Bit of a quiet period we're in storm-wise thanks to cool westerly and northwesterly winds over the coming days, but not without some risk. 

Today

A small risk of catching a storm or at least a heavy shower across SE England and E Anglia this afternoon as skies brighten following clearance of morning cloud and rain.

Storm & Convective Forecast

Issued 2016-07-27 07:55:29

Valid: 27/07/2016 0600z to 28/07/2016 0600z

CONVECTIVE/STORM OUTLOOK - WEDS 27TH-JULY-2016

Synopsis

Upper low persists to the north of the UK centred over the Norwegian Sea, driving a deeply cyclonic westerly flow across the UK. Surface low crossing southern Scotland overnight is now moving east across the North Sea, trailing frontal system bringing cloud and rain across England and Wales will slowly clear this afternoon, the SEward-moving cold front clearing Kent this evening.

... SE ENGLAND and E ANGLIA ...

Residual surface moisture following clearance of cold front, clearing skies allowing insolation and dry mid-levels will create some modest instability (100-300 j/kg CAPE) to develop this afternoon across the above areas in sunny spells that develop. Therefore there is a risk of heavy showers and a few thunderstorms developing. Vertical shear will be weak and CAPE modest, so no severe weather is anticipated. 

Tomorrow

Surface low moves east across the far north of England during Thursday afternoon, GFS shows several 100 j/kg CAPE developing across N, central and E England, ascent created in vicinity of triple point and cold front combined with lift of shortwave moving east aloft, dry air intrusion across S/central England enhancing instabilty. Strong wetserly  jet streak aloft and veering winds as low moves through indicated to yield 30-40 knts of DLS and 15-20 knts of LLS ... which maybe sufficient for organisation of storms. Lightning wizard shows a STP (significant tornado parameter) across N and E England.

Friday

BBC/Met Office forecast indicates potential for heavy and perhaps thundery showers for SE UK, though GFS not highlighting sufficient CAPE away from eastern Scotland atm.

[carinthian]

This has been the best summer for thunderstorms widely across the Alps for quite a number of years. Still plenty to look forward to over the coming days. Ripe situation with minimal pressure difference, rising air masses and a fairly active cold front moving in from the west. A big one at the moment over Lake Como and growing. Some recent development across Germany with a developing strong sheer zone for the east and southeast of the country. Will be peak watching later, especially if this low cloud clears fro around these parts. Nice to see the UK getting some activity recently and as Nick reports some possible later for you.

 C

[Frosty hollows]

Very warm and oppressive despite the dark heavy clouds. Wouldn't be surprised if some of these showers turn heavy

[carinthian]

3 hours ago, carinthian said:

This has been the best summer for thunderstorms widely across the Alps for quite a number of years. Still plenty to look forward to over the coming days. Ripe situation with minimal pressure difference, rising air masses and a fairly active cold front moving in from the west. A big one at the moment over Lake Como and growing. Some recent development across Germany with a developing strong sheer zone for the east and southeast of the country. Will be peak watching later, especially if this low cloud clears fro around these parts. Nice to see the UK getting some activity recently and as Nick reports some possible later for you.

 C

There she goes . Storm clouds developing. Substantial cell development looking towards the South Tirol. Steady rain here at the moment. Lot of electrical activity in Southeast Germany at the moment . Reports of damage in the Liepzig region.

 C