Convective / Storm Discussion - 23rd August onwards 2013

[The PIT]

Maybe some stuff brewing round us. I want some heavy rain so I can was the car and not have to rinse it off.

Would be nice if the Met Office updated the warnings the present one is getting a bit old now.

[Darren Bown]

The rotation of the rain band in the SE is quite spectacular. I presume that is pulling in the humid air from the south?

[Coast]

I'm in Maidstone today, so perhaps in a prime location for action today?

 

Possibly more to the South, which is great with me!

 

[Guenhwyvar]

Got heavy rain and thunder and lightning here.

[Coast]

Been back a few pages and didn't find reference to these, apologies if it's already been posted:

 

ESTOFEX

 

 

 

... Ireland, Cornwall, Normandy ...

 

A frontal wave and another potent short-wave trough travel southward from the afternoon hours onwards. Neutral profiles and strong forcing might allow isolated thunderstorms, either along the cold front or on the cool side of the boundary. With deep-layer shear around 20 m/s, marginally severe wind gusts are not ruled out.

 

 

 

UKASF

 

 

 

Synopsis

 

Atlantic trough disruption allows surface cyclogenesis to occur across central/eastern Britain and nearby Continent. Around the base of a broader upper trough, a couple of discrete cut-off upper lows will drift southeastwards, with a strong jet on their southwestern flank.

Discussion

 

.. NE/E/SE/CS ENGLAND, E/SE SCOTLAND, SHETLAND ...

 

A warm, humid airmass in place at the surface will continue to destabilise as a surface cold front moves slowly eastwards, and sharp upper trough (turn cut-off low) drifts southeastwards towards northern France. Embedded convective elements are expected along the main frontal zone, capable of producing some occasional lightning given ELTs down to -10C to -20C locally. However, lightning activity is not thought to be too widespread from elevated convection.

 

Some models simulate surface development during Saturday along a zone of convergence along/east of the Pennines southwards to the northern/northwestern Home Counties. Given ample surface moisture, frontal and convergent forcing and any brief cloud breaks, there is scope for a few surface-based convective showers and/or thunderstorms to form during Saturday, with a continuation of more generic dynamic rainfall further east (with still occasional embedded convective elements). However, confidence remains fairly low on this occurring at this stage, and thus have refrained from introducing a narrow SLGT zone for this potential for the time being. Shear is rather meagre, thus produce a rather messy picture. Main concern, however, given PWAT of 30-35mm, is the risk of local flash flooding considering slow movement of torrential downpours in places.

 

... IRELAND, CORNWALL ...

 

Showery outbreaks of rain along an occlusion will spread southeastwards during the afternoon and evening hours. Again, instability is rather weak, so lightning activity is unlikely to be widespread (hence only an ISOL), but the odd embedded cell may be capable given ELTs down to -30C in places. Some 30-40kts DLS as the left exit of the jet aloft overspreads the area may allow convective elements to cluster into linear segments in places. As such, any stronger cell may be capable of producing some small hail and locally heavy downpours with PWAT near 30mm.

 

Edited August 24, 2013 by Coast

[Darren Bown]

Estofex doesn't really like us today. I'm almost as south as you can get and still not 'far south enough lol.

[wimblettben]

Well as expected didn't get anything overnight here.

 

Hoping we may get something later.

[Coast]

Estofex doesn't really like us today. I'm almost as south as you can get and still not 'far south enough lol.

 

Dan (Staplehurst) at UKASF does though and I'm liking the prospects a little more now too:

 

 

Right over Sussex through the Morning:

 

 

 

Come to Daddy!

 

 

Still lots of rain about for most of today here:

 

 

 

Spout index also of interest for some:

 

 

Steepening lapse rates:

 

 

 

and big moisture transport vectors:

 

 

 

Just got to hold on tight and watch the radar now!

Edited August 24, 2013 by Coast

[Coast]

I know this is nowcasting, but the often maligned TT Index is about right for this morning from NMM:

 

 

 

 

 

 

 

[TEITS]

We had some very impressive lightning and thunder last night around 3am which woke me up. I didn't manage to capture any this time as I was too tired to get up.

[jamesslater93]

Absolutely throwing it down here, some thunder and lightning too.

 

Just as I type, what I believe is called shotgun thunder, never heard thunder that loud before!

[Guenhwyvar]

Absolutely throwing it down here, some thunder and lightning too.

 

Just as I type, what I believe is called shotgun thunder, never heard thunder that loud before!

Just heard that.It was amazing

Edited August 24, 2013 by Guenhwyvar

[Captain Shortwave]

I like how it's chucking it down in the north east and south east, yet in the middle it's just persistent light rain, same old story as one would say 

Edited August 24, 2013 by Captain shortwave

[Guest William Grimsley]

Dan (Staplehurst) at UKASF does though and I'm liking the prospects a little more now too:

 

 

Right over Sussex through the Morning:

 

 

 

Come to Daddy!

 

 

Still lots of rain about for most of today here:

 

 

 

Spout index also of interest for some:

 

 

Steepening lapse rates:

 

 

 

and big moisture transport vectors:

 

 

 

Just got to hold on tight and watch the radar now!

Thunder for Cornwall? :O

Been back a few pages and didn't find reference to these, apologies if it's already been posted:

 

ESTOFEX

 

 

 

UKASF

 Interesting.

[Darren Bown]

I like how it's chucking it down in the north east and south east, yet in the middle it's just persistent light rain, same old story as one would say

If it helps, although there are heavy rain pulses here, I've got bright skies and light rain.

Apparently in Westhoughton, Bolton, they had a terrific storm around 2-3am! So unlucky, moving south for the weekend.

[Guest William Grimsley]

Apparently in Westhoughton, Bolton, they had a terrific storm around 2-3am! So unlucky, moving south for the weekend.

Lucky people!

[multi cellular thunderstorm]

Did an amazing job of missing everything here so far. The ground is dry and was only slightly dampened for a few minutes last night.

I don't have very high hopes for today, but I'll certainly be keeping an eye on the radar.

[Supacell]

Everything appears to now be moving from N to S, certainly around here as we are now on the western flank of the developing low. Forecast is for the rain to pull back west later. If it turns thundery then I may get another bite at the cherry, but I think it will be a long shot.

[Craigers]

As promised here is a photo from last nights storm!

Hope you all like it

[viking_smb]

excellent pic

[Harry]

Skies starting to look more dynamic here - darker to my south, with a nice cumuliform lump to my west. Winds are quite brisk at low-mid altitudes. Still on the stagnant muggy side too.

[Craigers]

excellent pic

Thanks viking_smb

[Darren Bown]

Feels fresher in Maidstone, than it was last night. I imagine the humid air is more east of here, pushing back west during the day.

[Keraunic]

As promised here is a photo from last nights storm!

Hope you all like it

P1090500 webedit1.jpg

 

Brilliant capture, Craigers. well done and thanks for sharing such a great photo.

[East_England_Stormchaser91]

Some good looking developing stuff over Belgium at the moment, hopefully that will cross over to us and intensify as it does(wishful!). Meanwhile across the SE/EA, showers developing moving generally NW, but at a snails pace and are all over the place!

Edited August 24, 2013 by East_England_Stormchaser91