Convective / Storm Discussion - 23rd August onwards 2013

[Guest William Grimsley]

Lots of cumulus congestus clouds around, now. It seems like the cap in the atmosphere is too low, though. Most of them seem to be accelerating upwards then dying. Maybe some showers, later.

[East_England_Stormchaser91]

As this thread is dead as a dodo at the moment, heres a cam of Palma, some decent lightning strikes about there, they have been having some insane activity throughout today. http://hdtv.webcam.nl/website/page1/page18/PTZ_WebCam_Palma_de_Majorca.html 

[Guest William Grimsley]

As this thread is dead as a dodo at the moment, heres a cam of Palma, some decent lightning strikes about there, they have been having some insane activity throughout today. http://hdtv.webcam.nl/website/page1/page18/PTZ_WebCam_Palma_de_Majorca.html 

I saw that earlier, a great thunderstorm!

[Flipflop]

Is this it? or is there some hope way out in noddy land to grace us with a crack or two..... OR are we now looking for Thundersnow now to give us a flash or two BABOOOMMM...

Electric blue flash with big flakes and the thud that rattles the windows on quiet nights when all is quiet on the roads when you can set up a tripod in the middle of the road...as you do

 

Restless and sick of taking pics of stuff of stuff.

[poseidon]

Given the lack of UK storms again atm, take a look at this 8 min vid I shot on Sunday morning before sunrise in Italy. The intensity ramps up through the video as the storm passes over my location (on top of a hill). It occurred on the boundary between Estofex level 1 and level 2 alert areas. I abandoned filming in the end as rain was pouring in. The wind was so high (the foreground trees were being battered from 6:00 onwards) that there was quite a force on the window. Listen to it on headphones with the volume up for best effect and make sure your laptop screen is at the right angle as it's quite dark. Quality's not great as it's shot through a mosquito mesh, I was getting hosed with rain and YouTube seems to have lost the HD resolution. Gives an idea of what it was like though. Once I stopped filming there were a number of extremely loud shotgun thunder claps right overhead that vibrated the building. It lasted 2 hours. I was pretty lucky as we had 4 thunderstorms while I was there, this being the best of the bunch.

 

http://youtu.be/5IS1sUV7WUQ

 

Here's what Estofex had to say...

 

Storm Forecast
Valid: Sun 25 Aug 2013 06:00 to Mon 26 Aug 2013 06:00 UTC
Issued: Sun 25 Aug 2013 05:27
Forecaster: VAN DER VELDE

A level 2 was issued for Italy and northwestern Balkan mainly for severe convective wind gusts and large hail.

A level 1 was issued for Italy and northwestern Balkan mainly for severe convective wind gusts, large hail and tornadoes.

SYNOPSIS

A multicore low pressure system is situated over France, Germany and northern Italy. Cool airmass has entered France and the northwestern Mediterranean. Warm unstable airmass is sticking around Italy and the western Balkan, as well as in a small pocket over eastern Spain. An occluded front with weak conditional instability stretches from the Alps to the Netherlands. From Czechia to Moldova it has the form of a warm front. A merry-go-round of shortwave upper troughs affect Netherlands, western France, northern Italy and Hungary.
An occlusion of another low with a zone of unstable air is present over western Russia. Northern Africa is also active and very high-based.
Model buoyancy profiles look weak in the mixed phase region over France, Germany, Romania and Russia, with reduced potential for significant electrification and hail production.

DISCUSSION

...Italy, Slovenia, Croatia and surrounding area...

A large area with 500-1500 J/kg MLCAPE and 15-20 m/s deep layer shear is expected to continue producing severe storms. The Adriatic CAPE is a bit more capped. The highest potential is over northeastern parts of Italy and the northwestern Balkan, because these areas are crossed by upper shortwave troughs which can destabilize mid levels and enhance upper winds and shear. GFS model hodographs appear the roundest over eastern Italy, while over Slovenia and Croatia they look more helical in the lowest levels. Supercells and mesoscale convective systems are the expected mode. Large hail is likely. Of particular interest is delta-theta-e, enhanced over 16-20K over a large area, apparently created with help from cooler, drier mid level air behind the mid level cold front overrunning the warm moist low level air. This parameter suggests enhanced downdraft intensity with severe gusts, and combined with mesoscale forcing widespread damaging winds may occur. Tornadoes are not that likely given a not very low cloud base height and somewhat weak 0-1 km shear, but local orographic enhancing factors combined with veering profiles in a large region probably will allow an isolated event.
After the big storms, (18Z and later) waterspout tornado potential increases over the northern Adriatic as low level lapse rates steepen during the night as cooler air comes in.

Edited August 26, 2013 by poseidon

[Coast]

Very quiet this week coming:

 

 

 

[Guest William Grimsley]

WOW! 52% storm chance for me, this evening! Look at the UK storm risk chart for 19:00!

 

Still, the UK CAPE+Lifted Index chart doesn't look that amazing with a UK CAPE of 200 - 300 j/kg and a Lifted Index of 0!

 

[Coast]

WOW! 52% storm chance for me, this evening! Look at the UK storm risk chart for 19:00!

 

Don't get too carried away William, you might be a little disappointed today (and this week)

[Guest William Grimsley]

Don't get too carried away William, you might be a little disappointed today (and this week)

Well today will see some activity, I know this week is looking quite quiet, though.

When you've got clouds like altocumulus castellanus and cumulus congestus peppering the sky, something must be going on.

[Supacell]

I have an awful feeling this years storm chase season may be coming to a close. If it does then i will have mixed feelings about 2013. Probably the shortest storm season i have seen since i started chasing with all the decent stuff falling in a 2 week period. However that 2 week period was littered with very active storms that are some of the best i have seen since those days as a kid when i would watch them from my bedroom window.

[Guest William Grimsley]

I have an awful feeling this years storm chase season may be coming to a close. If it does then i will have mixed feelings about 2013. Probably the shortest storm season i have seen since i started chasing with all the decent stuff falling in a 2 week period. However that 2 week period was littered with very active storms that are some of the best i have seen since those days as a kid when i would watch them from my bedroom window.

I have to agree. Only 1 thunderstorm here on 02/08/2013 and some showers. Was quite a boring thunderstorm season.

Edited August 27, 2013 by William Grimsley

[Supacell]

I have to agree. Only 1 thunderstorm here on 02/08/2013 and some showers. Was quite a boring storm season.

2nd Aug saw a fantastic storm near here with almost constant flashing from a browny black sky that then produced hail, wind and torrential rain as it passed over. It moved fast though so didn't last too long.I have seen good storms in October before so i suppose its early to call the end of the season but its just a hunch.

[Guest William Grimsley]

2nd Aug saw a fantastic storm near here with almost constant flashing from a browny black sky that then produced hail, wind and torrential rain as it passed over. It moved fast though so didn't last too long.I have seen good storms in October before so i suppose its early to call the end of the season but its just a hunch.

Yeah it was a fantastic day thunderstorm wise.

 

Yeah hopefully some more action this year. 

[Guest William Grimsley]

Run 06z is now out and nothing much has changed with the UK storm risk chart except higher chance further S than me now, still in the 40% boundary, though.

 

[andymusic]

little surprise today - couple of rumbles of thunder - and now some heavy thundery rain - very localised - but hey!

[A.J]

just to add to my post in the south west regional, some lively showers and thunderstorms are breaking out over South Devon, more particularly Newton Abbot (not poppleford..lol) Torquay & Totnes moving in towards Plymouth

 

 

image courtesy of NetWeather.tv

[nitro_deluxe]

Very isolated heavy shower poss storm over C Wales too, W of Welshpool.

Edit, looking quite an active one at that, Newtown area.

Edited August 27, 2013 by triple_x1

[poseidon]

Some new research on tornado tracks....

 

http://phys.org/news/2013-08-tornadoes-tend-higher-elevations-greater.html

[philglossop]

Absolutely black as the ace of spades to the North and East of us here. Heard some thunder about an hour ago towards Ermington/Yealmpton way.

 

Very very humid as well.

[nitro_deluxe]

Indeed, showing up well on radar - pretty localised affairs that will deliver or should you be beneath them. Then hardly a drop just a few miles either side.

Absolutely black as the ace of spades to the North and East of us here. Heard some thunder about an hour ago towards Ermington/Yealmpton way. Very very humid as well.

[Raidan]

Why does it say that currently in Bristol the weather is thunderstorm? That's obviously a mistake as there definately isn't!

[Convective]

Seems like Thor has retired This is the best time of year now around these areas for thunderstorms as the sea is warmer than the air but without the energy in the atmosphere you get flat cloud.. and there isn't much energy around for a while yet! Off to Tenerife in late October into early November so if we can get a nice, big, fat, juicy high over the UK then to shift all the lows down over the Canaries then I'll will be satisfied until the next UK storm season. Albeit that won't happen until I'm 80 and in a care home....... 

Edited August 27, 2013 by Convective

[Guest William Grimsley]

A bit disappointed that I didn't get any showers, today. All of the showers went SW of me. I wish I could of been in them or they had come over here. Some of them were very heavy with hail and thunder and lightning!

[paul m]

Seems like Thor has retired This is the best time of year now around these areas for thunderstorms as the sea is warmer than the air but without the energy in the atmosphere you get flat cloud.. and there isn't much energy around for a while yet! Off to Tenerife in late October into early November so if we can get a nice, big, fat, juicy high over the UK then to shift all the lows down over the Canaries then I'll will be satisfied until the next UK storm season. Albeit that won't happen until I'm 80 and in a care home....... 

Remember going to Tenerife when i was about 12. Thunderstorms every night loved it

[Guest William Grimsley]

Remember going to Tenerife when i was about 12. Thunderstorms every night loved it

When I've been on holiday, I've been in several thunderstorms. A few thunderstorms in France, 1 thunderstorm in Majorca, 1 thunderstorm in Croatia and 1 in Portugal.