Storm & Convective Discussion 12z 21/7/14 ------>

[Supacell]

A bit taken by surprise by this as did not expect anything convective from it but the rain band pushing east appears to be producing the odd sferic on it's back edge.

[Joey.G]

You're right there Joey, fantastic storm passed over us for about an hour, plenty of Lightning and cloud rotation too, passed NE though, not sure if you are inline or not. It really built out of nothing and intensified, I got very excited about the cloud rotation but it moved off on its merry way taking the rotation with it into the distance. Some pics:

 

Ahh lucky you! Sounds great, it's always nice to hear a report from the front line when your looking at something on the radar, even better when theres photos! Doesnt look like we're going to get anything here, electrical activity has died away.

[pip22]

A few strikes off the coast of Lancashire:

 

http://www.lightningmaps.org/realtime?lang=en

[SparkleS]

Weve just had lightening

[Supacell]

Looks like a chance of some thunderstorms today across more northern parts of the UK with the best area looking to be an area from the NW of England by the middle of the day into NE England by late afternoon/evening. There seems quite good agreement on this, with perhaps somewhere along that NE Yorkshire coast likely to see the best chances.

 

Although CAPE is fairly good (nearly 1000j/kg and a LI -4 to the north of the Humber) there is little in the way of deep or low level shear and so storms are unlikely to be organised or severe. However, there does look to be a number of convergence zones across northern England which could help to focus storms in certain areas and with downpours likely to be torrential this could lead to localised flooding despite the fact storms shouldn't be too slow moving. A risk of hail and CG lightning also.

 

It's a complicated set up through the rest of this week with tomorrow currently looking like the least likely day for any storm activity (but this could change). I do have my eye on Friday night, it is a long way off and with the models chopping and changing as much as they are I am not going to go into too much detail at this stage, but the latest charts show some interest for us storm fans The weekend brings more possibilities too, so not boring by any means.

[Weather-history]

Weve just had lightening

Caught it on the time lapse last night. Also between 16s and 22s near the horizon in the bottom right you can see some flashes.

[Biggin]

Weve just had lightening

Grrrrrrrrr. lightning lightning lightning

[Mokidugway]

Hour long storm between 1030 and 1130 last night ,plenty of lightning ,nice .............

Edited August 6, 2014 by Mokidugway

[Summer Sun]

We had some torrential rain, thunder and lightning around 03:00 the side of the road was like a river for a time

[Greeny]

In and around Norwich some thick dark clouds in contrast to blanket light cloud, rain from light and sometimes quite heavy in places. No t heard or l seen.

Just been through a torrential downpour near Acle Norfolk. Sky went very dark.

[Paul]

Certainly pretty damp overnight for many of us, as shown on the radar totals. 

 

 

As Supacell mentioned above, it's the northern half of the UK and across parts of of Ireland and Northern Ireland where the highest storm / hefty shower risk exists today. A couple of charts from our new (still in testing) NMM model.

 

 

TT index is something some of you may not be familiar with, it's a simple index which gives a rough guide to the storm risk - higher the index the more likely storms are. Anything above 45 means convection/storms are possible, above 50 and there's the risk of some more intense storms.

 

 

[Nick F]

Storm & Convective Forecast

Issued 2014-08-06 09:58:40

Valid: 06/08/2014 1000z to 07/08/2014 0600z

 

 

THERE IS A RISK OF THUNDERSTORMS FORECAST

Synopsis

Long-wave upper trough and surface low pressure system to the NW of the British Isles drives a cyclonic SWly flow across the UK on Wednesday. Occluded front - which brought heavy overnight rainfall, will clear all but the far north of Britain by afternoon, with airmass unstable to surface heating following across much of the UK.

 

... ERN EIRE, N IRELAND, N ENGLAND, S SCOTLAND, S and E ENGLAND ...

 

A fairly broad area of the British Isles will be in a moist SWly flow which will be unstable to surface heating, instability enhanced by drier and colder mid-level air flooding in aloft from the west. GFS develops 300-700 j/kg CAPE as a result across the above areas of the UK Weds PM. So heavy showers and thunderstorms are forecast to develop, Vertical directional shear will be rather weak today, though local wind convergence may allow storms to cluster/merge to bring a risk of large rainfall totals in a short space of time, leading to flash flooding. Also, storms may produce hail to 1-2cm diamater and gusty winds. The greatest risk of low-end severe weather (mainly localised flooding) is likely to be across S Scotland and NE England - where local breeze convergence is indicated, though other parts of UK/Ireland indicated may see a few more localised thunderstorms too.

Issued by: Nick Finnis

Edited August 6, 2014 by Nick F

[toggerob]

Had a rumble of thunder here in the past minute from the shower passing to the south towards Buxton.

[Methuselah]

It certainly feels as if we're in for something. It's as muggy as Hell!

[Polar Maritime]

Thunder over Edale way, Sky is black. Heavy shower stopped here for now.

[Guest]

A few strikes out to the west with the shower imminent in the next 20 minutes. Hopefully still electrical when it gets here.

[Greeny]

It certainly feels as if we're in for something. It's as muggy as Hell!

Reasonable theta - e values and dewpoints in the higher teens I guess rain water evaporating too :-) feels very hot in the sun, plenty of heat for higher levels of moisture in the air.

[Guest]

Yep, dark skies to the west and a rumble of thunder just now. Excellent

[Guest]

Good little storm this Had five rumbles in the last few minutes.

edit: seems to have lost it's electrical activity now after a good performance earlier. Missed us to the south so not much rain to speak of. Plenty of towers going up all around though!

Edited August 6, 2014 by SjV

[Utahraptor]

Some nice cumulus clouds here, hope they build up to something later in the day

 

Edited August 6, 2014 by Utahraptor

[Supacell]

A number of strikes across Lincolnshire currently; looks the place to be so far this afternoon. I still expect the main thrust of storm activity to transfer around the Hunber and north along that eastern side by tea time/ early evening.

Heavy shower here around lunch time but no TL. Feeling warm now in the sunshine.

[vladthemert]

just had shower from storm system which now in north sea looks like attempting to funnel with lovely vortices in development.

 

 

Just been reading about bertha it downgrading noticed this still can hit anywhere but news focus is most likely, storm tracking.  I just checked latest its speed gone upto 43 kts whether its upgrading again too early.

 

http://www.towndock.net/weather/tropical-system-3

[Mokidugway]

Just watch those storms over Northern Ireland die when they cross the Irish Sea !!.....

[Mokidugway]

And start up again on the other side !!...

[Jan]

I was just driving home from work and saw some huge towers out towards Warrington/Chester way?