Storm Reports for 15th August

[kar999]

Guess I'll start a new thread......

Just heard thunder rumbling in the distance from increasing banks of dark clouds to the South.

[Andy Bown]

Beautiful approach of the front with low CB bases and high anvils lit up by bright sunshine. It really was a great contrast to be here in sunlight and watch the jet black edge closer - even saw two sheets of lightning while the sun was shining :lol: . Something of a gust front developed and there was the hint of rotation with some fast moving scud (definitely no funnels visible). When the sun went in it was possible to see the front stretching right from the WSW to the ENE with torrential rain nearby.

I really think it gained strength over the Mendip Hills as watching the lightning returns on NW Extra they intensified between Bristol and here. I saw plenty of sheets, a few IC streaks and 2 CGs the other side of town. The rain was sporadic for 15 minutes and then torrential for about 20 minutes as it passed right overhead - 2 overhead flashes and rumbles just after 16.00 and over the last 15 minutes thunder has gradually become quieter as it's headed over Salisbury Plain.

The wind was very gusty from the SW while the pre-storm sun was shining, before dropping to calm during the storm and now we have a gentle WNW.

After wading into the garden I've just found 20mm of rain in the gauge!

(This will also be posted in storm reports).

[johnholmes]

nice concise report there Andy, tks

how about the temp and dewpoint through that period?

If you have an auto wx stn and its linked to the web it would be good to see the various parameters?

[Andy Bown]

nice concise report there Andy, tks

how about the temp and dewpoint through that period?

Hi John, thanks for the compliment. I have no dewpoint readings - would refer to the likes of Lyneham, Yeovilton, Boscombe Down and Larkhill for them. However the max temp I have for today is 22c (which would have been pre-storm) and the temp now is 16c, so that's an impressive drop.

[johnholmes]

cheers

[Greeny]

To add in Norwich near where I live I'm pretty sure I saw weak rotation in a cloud base that I was watching. Clouds just dropping down at a small portion from the main cloud seemed to be moving in opposite directions possibly a weak meso, Ive certainly seen that kind of rotation on tornado videos so looked familiar. It seemed to dissipate as it moved away. I think there was lightning in the storms that came past but never saw them although some mamotus certainly passed over.

[Greeny]

A larger cape according to the SKEW T chart now to when I saw it yesterday. The above suggests to me that the cloud base will be around 1800 feet or even lower and the cloud tops being around 22000 feet (John Holmes accurate estimation or not?) . Rain and dark clouds are coming over now but no lightning or thunder. Shame the cloud tops can't be a little higher and more cape and less Li hehe!.

[Sugar79]

http://www.torro.org.uk/torro/forecast/index.php

:lol:

[johnholmes]

A larger cape according to the SKEW T chart now to when I saw it yesterday. The above suggests to me that the cloud base will be around 1800 feet or even lower and the cloud tops being around 22000 feet (John Holmes accurate estimation or not?) . Rain and dark clouds are coming over now but no lightning or thunder. Shame the cloud tops can't be a little higher and more cape and less Li hehe!.

can't argue with your tops predict, with the temp and dewpoint shown I would suggest the base would be a fair bit below 1800ft, but it looks fairly unrealistic unless its a predict of the ascent through a storm.

perhaps you might pop your town/area into your avatar please?

many thanks

[kath29]

thunder and lightening about 2 o clock today

[Greeny]

Great thanks John I've been reading off SKEW T charts for a little while now and I started off with your tutorial (was a great help thanks) and I believe I'm getting used to how they work and what I've learnt about them has been quite alot. I guess there is a bit more of it I need to learn but its nice to get a 2nd opinion from time to time so I know I'm not reading it wrong and to affirm what I've learnt I've understood properly.

I thought the clouds could have been lower than 1800 ft but I think I was playing it safe. I certainly saw very low clouds passing over from time to time.

Thanks Sugar for the link to torro. I guess then it was a weak meso I saw and I wasn't just mad. The storm itself however wasn't intense enough to create even at least a funnel cloud but it was certainly interesting knowing it passed behind my house and I hadn't observed one before.