Storm & Convective Discussion - 1 September 2015 onwards

[marksp]

well had an eventful holiday on costa del sol, great weather and witnessed an amazing storm over the mountains of Nerja.

best lighting I have seen ever, plenty of videos mainly on phone but one on a camera. will try to upload on to youtube and then post link but the storm was a special one.  BELIEVE ME when i say in real life it was special !!!

[Costa Del Fal]

Met office mentioning the risk of thunderstorms or thundery showers moving east tonight. Interesting but can't see much of a risk myself!

[pinball wizard]

well had an eventful holiday on costa del sol, great weather and witnessed an amazing storm over the mountains of Nerja.

best lighting I have seen ever, plenty of videos mainly on phone but one on a camera. will try to upload on to youtube and then post link but the storm was a special one.  BELIEVE ME when i say in real life it was special !!!

 

Great pic, cheers for sharing

[IanR]

Met office mentioning the risk of thunderstorms or thundery showers moving east tonight. Interesting but can't see much of a risk myself!

risk of  thundery showers in western coastal areas according to the forecasts,  but doubt anything for the irish sea areas of north west england,   it will be the usual areas that will probably get the thundery stuff,   ie  channal coastal areas ,  dorset to isle of wight maybe , and eastwards from there 

[Thunderbolt_]

This is my take on tonight. It all looks very marginal to me in the west, so I think the area with the greatest risk of thunder will be the south coast.

 

[NO LONGER POSTING]

This is my take on tonight. It all looks very marginal to me in the west, so I think the area with the greatest risk of thunder will be the south coast.

 

Risk of thunder - 210915-220915.png

 

Good take on things given the models look all different.. 

 

What about this!

 

 

 

 

Thats some wrap around where ever it occurs! IF it even does!

[virtualsphere]

risk of  thundery showers in western coastal areas according to the forecasts,  but doubt anything for the irish sea areas of north west england,   it will be the usual areas that will probably get the thundery stuff,   ie  channal coastal areas ,  dorset to isle of wight maybe , and eastwards from there 

 

This is my take on tonight. It all looks very marginal to me in the west, so I think the area with the greatest risk of thunder will be the south coast.

 

I'm in an area which is prone to this kind of activity and so tonight will be interesting, although the peak for here seems to be November - January with occasional thundery episodes in October and February.  September has been one of the quietest months here for convective activity in recent times, although that might be because of the synoptics we've had rather than because September can't deliver under the right conditions.  

 

I also wonder about the effect of the cooler Atlantic this year on coastal thundery showers - if I understand correctly the storms are triggered because of the temperature difference between the sea and land, as the warmer air over the sea is forced to rise as it hits the cooler land.  Therefore, under normal circumstances, we get storms in a cyclonic autumn / winter SW'ly because the sea cools at a slower rate than the land, creating a greater temperature difference than in spring / summer (when the sea takes longer to warm up).  So, if the ocean is cooler than usual, presumably this would inhibit storm development?

[Spikecollie]

Nothing much being exported to the UK from my side of the channel here in France. It's been a beautiful few days with low to mid 20s, although I've been working and haven't got out in much of it. Lots of very varied clouds about tonight here in Limousin and light to moderate rain progged for tomorrow, but then we're back to nice again.

[Nick F]

CONVECTIVE / STORM OUTLOOK TUESDAY 22ND SEPTEMBER

 

 

Issued: 21-09-2015 2130z

Valid: 22/09/2015 0000z to 23/09/2015 0000z

 

Synopsis

Break-away upper low/trough moves SE across southern UK during Tuesday. At the surface, area of low pressure will be slow-moving over the North Sea, while a secondary wave/low moves ESE across Wales then southern England, exiting into southern N Sea early afternoon.

 

... IRELAND, WALES, IRISH SEA, W and S ENGLAND ...

 

Upper low and associated mid-level cold pool (-20C to -25C at 500mb) will steepen lapse rates atop moist maritime airmass, producing a pool of a few 100 j/kg CAPE. This pool of instability, currently over Ireland producing a few thunderstorms, will move across Wales, western and southern counties of England Monday night, through Tuesday morning and early afternoon, supporting an increase in heavy showers and scattered thunderstorms moving E, before more stable airmass moves in from the NW by early evening. 

 

Any showers or thunderstorms maybe accompanied by hail, gusty winds and torrential rain leading to localised flooding. Strong winds aloft and modest 0-6km layer shear (30-40knts) in the morning towards SW and far south of England may allow organisation of storms here and through the English Channel, perhaps bringing isolated strong convective wind gusts (35-40knts) and, combined with strong updrafts over warm SSTs around southern coasts - isolated large hail (1-2cm) and localised flash-flooding (25-40mm in a few hrs in a few spots). Vertical shear weakens considerably by early afternoon, so severe threat weakens. But have issued a MARGINAL risk for S Wales, SW and far S of UK. There is also a chance of funnel clouds or even one or two brief/weak tornadoes with stronger storms moving near or  along a wind shift or convergence zone towards centre of low crossing E over S England during the morning.

 

Issued by: Nick Finnis

Edited September 21, 2015 by Nick F

[Flash bang flash bang etc]

I will be in Sittingbourne tomorrow hopefully a good place for storm's but maybe not I don't know. Fingers crossed eh?

[William Grimsley]

Well, looks like nothing happened thunder wise! 

[NO LONGER POSTING]

Well, looks like nothing happened thunder wise! 

 

No, but check out the rain in the South east STREWTH! 

[Wilxy]

A damp morning after showery bursts of rain overnight 10.4mm of rain recorded overnight.

[sunnijim]

25mm now in SE London since 430am,alot of 'pavement bouncer' convective drops.

[NO LONGER POSTING]

Holy moly!

 

[Eye to the sky]

Holy moly!.I agree some spectacular cloud formations today giving some isolated but heavy showers especially around here.Had the windscreen wipers on fast mode as we came back from Mansfield around an hour ago.Apart from that a pleasant day to be fair.

 

DSC_1134.JPG

[Flash Elvis]

Holy moly!

 

DSC_1134.JPG

Think you might have a drop of rain from that!!!

[Nick F]

Nice rope tornado/funnel cloud caught on video in Cambridge today:

 

https://www.youtube.com/watch?v=dtRFsZyY0cU

Edited September 22, 2015 by Nick F

[Dami]

wish I'd taken a pic, had the pleasure of watching a lovely storm/shower heading to me complete with towers and a lovely dark base. By the time I got home you could see how dark and rainy it all looked. I expected a nice heavy shower from it, but I actually got a few drops. Even the radar was showing bright echos. Oh well, it was a beaut. 

[Flash bang flash bang etc]

Squall line appears to be forming across the SE. Now heading into Sussex. Quite a nice little feature and looks to be intensifying a bit, too.

[Weather-history]

A few showers last night

[Thunderbolt_]

I found this video on YouTube. It is a time-lapse of the Blitzortung lightning detector for the whole of summer 2015. That surge of lightning over the UK between 2:00 and 2:12 was the incredible Spanish plume of 30 June to 4 July. Never will I ever forget that spell of weather!

 

[Mokidugway]

Just shows how bad we do compared to our southern neighbours !!.

Edited September 25, 2015 by Mokidugway

[East_England_Stormchaser91]

Glad i got to see and make the best of what was available this year (1st and 4th July, 16th July, 22nd August)!

[Costa Del Fal]

Had to laugh at the very end of that video, look how the sferics clearly stick to the English Channel only and seem to curve around our coast!!!