Storms Of 27th June , What Caused Them?

[Neilsouth]

I know how most storms develop however what caused them today ? , why did they become so vigorous in the west of south east up towards london?. Why was places like east kent , north kent spared the vigorous storms yet it was just as hot and humid here with numorus towers growing close by?

I also noticed the clouds change direction as the day went on , but we did have lower based cumulus coming from the north while storms generally traveled west , north and north west

B)

[Neilsouth]

LOL 0 Views

[maidstone weather]

I know how most storms develop however what caused them today ? , why did they become so vigorous in the west of south east up towards london?. Why was places like east kent , north kent spared the vigorous storms yet it was just as hot and humid here with numorus towers growing close by?

I also noticed the clouds change direction as the day went on , but we did have lower based cumulus coming from the north while storms generally traveled west , north and north west

With my little knowledge, a small surface Low developed right over Maidstone this afternoon. The storms developed to the east of Maidstone and stayed there for several hours, initially moving NW but as the Low developed the next batch moved more of a direct north. As i have been out all evening i haven't been able to keep up with the storms, but what i did notice is that as this surface Low moved away from Maidstone northwards into Essex, this meant the wind direction became a westerly and the storms over London moved eastwards across north kent this evening. Yet another day where central-west Kent and the extreme east Kent coast miss out!

http://212.100.247.145/fax/PPVA89.png

[Harry]

These are my thoughts, also on very limited knowledge I hasten to add - if anyone notes inaccuracies in the below, please tell me as it will aid my education and prevent me sounding like a plonker in the future!

I think the storms across London were caused by a combination of the higher temperatures, especially over London (UHI), and a CZ which was forecast to build along the Thames Valley region. There were very differing wind directions (as I think was visible to almost everyone in the SE) at different altitudes, and even seemingly same altitudes. This I think meant in some locations, it was a benefical wind shear scenario, while in others it caused more to wreck the developing storms than help them grow. There were plenty of examples I could see of towering Cu which when reached a certain height got smashed apart by differing wind directions, particularly aloft. Then of course there was the surface L which MW mentions - this helped I think streamline the storms, so anything which developed after the L formed tended to be more organised, while previous to this did appear more messy and destructive.

The storms along E Kent I think were helped by a sea breeze CZ - however the breeze (felt as far inland as here at times) noticeably dipped through the mid-later afternoon, which co-incided with the reduced activity at the same time.

What today's storms and the storms here around a fortnight ago seem to have in common, were that they were outside the main forecasted areas of CAPE/LI and storm risk. Kent having the London UHI affecting one end, CZ often forming along the northern flank along the Thames Valley, along with the coastal zones to N, E and SE means we do have a lot of CZ potential, along with often higher temperatures compared to other areas of the country. Being open to imports too is an added bonus .

This I think makes our small area of the world that bit more to predict as you can never really predict when strong sea breezes will develop, where they will develop and as a result, precisely say how that will interact with other weather patterns.

Edited June 27, 2009 by Harry

[Neilsouth]

Cheers both

[maidstone weather]

Cheers both

Sorry Neil, i forgot that link would change.

Luckily i managed to save a copy of the chart i was referring to from 7pm yesterday

[Phil UK]

Shallow LP development in your neck of the woods, hence why all storms over Kent appear to have become 'stuck'. It's not uncommon when there is a displacement of air masses, this being from the dry easterly as observed on Wednesday, then you have unstable air coming from two fronts, in this case SW and east. I last saw that in July 1989 when a front from the south met with one from Denmark stretching over into Germany.

Conclusion? One VERY severe thunderstorm over Coleshill/Solihull/Birmingham. I was coming home from work in Coleshill at the point that it all kicked off (About 5pm-ish) and I've never seen such extreme and frequent bolts of CG lightning as a storm from the south, and another from the east met in the same area.

But enough of my history lesson, you can wake up now.

Phil.