Convective/Storm Discussion Thread - 1st August onwards

[Andy Bown]

Some serious downpours in West Wiltshire this evening . We had hail half an hour ago and now very heavy rain. Thunder was heard to the North a while ago.

[tomp456]

Looking very black to the north over the downs! 

[ThundersnowDays]

Who else heard the big rumble of thunder a few mins ago?

[Methuselah]

7 minutes ago, tomp456 said:

Looking very black to the north over the downs! 

It's dark?

[matt111]

That line of storms in the channels been going on for hours now and not really moving anywhere. 

[biddie]

Been like that for days especially at night

[Julian 777]

Can see infrequent lightning over the channel..Earlier that lot was moving south but now there seems to be a more northward drift...I relly need some shuteye but will wait a few more mins..

[matt111]

Yes I noticed it looks like it's very slowly moving WNW now. 

[matt111]

Can see a bit on Bournemouth webcam.

https://www.sortedsurfshop.co.uk/webcam_bournemouth

[Julian 777]

Bournemouth/IOW looks like the best place to be at the moment.

 

[matt111]

If I was to walk down the road I'd probably get a decent view of it. Not going to this time of night though. 

[Julian 777]

Quote

 

Don't blame you ,but I would be tempted.

[matt111]

Looks like more developing just north of the main line. 

[Julian 777]

yea more sterics along that new line

[Julian 777]

off to bed now.. good luck with the cell near IOW !!

[Summer Sun]

Day 1 Convective Outlook

VALID 06:00 UTC Sun 17 Sep 2017 - 05:59 UTC Mon 18 Sep 2017

ISSUED 07:38 UTC Sun 17 Sep 2017

ISSUED BY: Dan

Upper vortex centred over NW Germany on Sunday will provide another showery day at least to England and Wales, though in general with quite dry air aloft showers should be a bit more isolated than on Saturday, but still sufficiently deep for some isolated or sporadic lightning - moreso towards East Anglia and SE England where elements of low-level convergence may aid forced ascent such as Essex-Herts-London drifting south into Kent-Surrey etc, and hence a SLGT has been issued here.

 

Overnight, focus then turns to the North Sea and Norfolk / Suffolk (and later perhaps Essex and Kent) as the cold pool aloft expands, and instability increases in response to warm SSTs. Showers and thunderstorms will probably become more numerous offshore overnight, these then drifting inland at times - and hence a SLGT has been issued.

 

Hail up to 1.5cm in diameter will be possible with the most intense cells, with perhaps a few funnel clouds and minor surface water flooding.

http://www.convectiveweather.co.uk/forecast.php?date=2017-09-17

[wimblettben]

Was up till 3:00AM last night looking at heat lightning in the distance to the south.

Judging by peoples posts on here from last night, I can't believe I was seeing lightning from storms at the coast as some of it was quite bright.

Very odd!

[MP-R]

Is it normal to have heat lightning in such a chilly airmass? I thought that was more typical of plume setups.

[wimblettben]

1 minute ago, MP-R said:

Is it normal to have heat lightning in such a chilly airmass? I thought that was more typical of plume setups.

I don't think it matters.

All heat lightning is is lightning which is too far away for the thunder to be heard, but because its nighttime its darker so therefore can be seen much further away then during the daytime.

Basically, as long as there is some kind of storm nearby at night, then you will see the lightning, just won't hear the thunder.

[alexisj9]

4 minutes ago, wimblettben said:

I don't think it matters.

All heat lightning is is lightning which is too far away for the thunder to be heard, but because its nighttime its darker so therefore can be seen much further away then during the daytime.

Basically, as long as there is some kind of storm nearby at night, then you will see the lightning, just won't hear the thunder.

Also the storms hight helps, i think last nights storms were very high based, also tbe fact they were over water shows this. I think the cause quite simply is the cold air fron the north over the warm waters.

[Methuselah]

Some pretty hefty looking activity to the east and south of here; the anvils over the North Sea look very interesting indeed.

[MP-R]

Fair enough, thanks for your replies!

[Chris.R]

2 hours ago, wimblettben said:

I don't think it matters.

All heat lightning is is lightning which is too far away for the thunder to be heard, but because its nighttime its darker so therefore can be seen much further away then during the daytime.

Basically, as long as there is some kind of storm nearby at night, then you will see the lightning, just won't hear the thunder.

 Yeah I think the word heat here refers to the phenomenon being seen commonly during elevated plume set ups in hot weather.  More of a traditional term rather than a meteorological one. 

[Allseasons-Si]

Hearing thunder to my east

[Julian 777]

2 hours ago, wimblettben said:

Was up till 3:00AM last night looking at heat lightning in the distance to the south.

Judging by peoples posts on here from last night, I can't believe I was seeing lightning from storms at the coast as some of it was quite bright.

Very odd!

I too was up till 4am in my case. Strange as through the afternoon quite a few Cb,s were moving over the South Coast from North to South but by night fall they seemed to stall at the French coast and head back to mid channel like a waving front..Wish I was on southern tip of IOW last night.