Storm/convective Discussion

[dogs32]

should be an interesting day even though things are not very electrical at present..

Now the sun is up

[Wilxy]

It is game over for me now midlands have best chance as it expected up there miday onwards great chance for storms then.

[SteveB]

Here a screen grab i took from the video footage i got from last nights storm also this was the strike that took out an electricity sub-station

Morning Mark,

I saw that strike hit the sub station. I was looking out of my skylight and saw the lightning hit the sub station, then saw a bright green light for around 3-5seconds.

Not a bad night last night, looking forward to more this morning.

BBC has us under these storms until lunchtime.

[Wilxy]

What storms there is no storms at the moment in the uk. If there are very weak and isolated.

[SteveB]

What storms there is no storms at the moment in the uk. If there are very weak and isolated.

Did you not see the forecast at 6.30am

I am guessing you missed out last night.

Well IF the bbc are right, then you should see something later.

Edited June 26, 2009 by SteveB

[Wilxy]

Did you not see the forecast at 6.30am

I am guessing you missed out last night.

Well IF the bbc are right, then you should see something later.

Its all died tho.

[A.J]

should be an interesting day even though things are not very electrical at present..

Now the sun is up

Pat, what are the skies like down your neck of the woods.....Just woken up here, peered out of the window, and all I've got is featureless uniform grey, and cant work out whether its thin low cloud, or high-level cirrus crud from the complex down south....I seriously hope its the former, which will burn off, otherwise the latter would infer that already today is going to be a non-starter :lol:

[Karen Ann]

Finally got a half decent storm here last night. Started in the distance with regular flashes and the odd rumble at about midnight. By 1am it was here. Funnily seemed to be coming from all directions, lots of bright flashes and a good amount of cracks and rumbles. It eased off at about 2.30am and by 3.30am it was gone. Good, long lasting storm for a change. I'm gutted though as I was unable to watch properly as my dear dog for some reason, decided that he wanted to bark his head off at every flash and every rumble (close or distant) - so I ended up in my daughters bedroom (which has black out curtains) with the door shut, sat on the floor trying to shut him up so that the rest of the house managed to get some sleep. Very odd, he normally sleeps through/ignores storms! Bah hum bug. Little sod.

[Andy Bown]

Andy is sat here with rain pouring down hoping for thundery activity to kick off :lol: ! There wasn't a drop all night & an hour spent between 02.00-03.00 glancing out of various directioned windows didn;t yield a distant flash either :lol: .

Fantastic photos by those who've shared them. It seems Somerset through to S.Wales caught the brunt.

Pylon has just been struck in front of my house.

Wow!

[Jane Louise]

Morning all,

I have a feeling it's going to be a non storm day here in my area. There is so much cloud cover and mist at the moment.

[SteveB]

What storms there is no storms at the moment in the uk. If there are very weak and isolated.

Maybe they are thinking given a bit of daytime heating and any breaks in the cloud, then it might pep up the showers again.

[twister2005]

Morning all, hopefully jane the sun will heat things up we are still under a weather warning :lol:

[Jane Louise]

Morning all, hopefully jane the sun will heat things up we are still under a weather warning :lol:

Let's hope so! we need the sun out to burn the clouds away. Maybe our storms will be this afternoon :lol:

[SteveB]

We have light rain here at the moment.

Very warm already 16.2c

And muggy

Edited June 26, 2009 by SteveB

[Nick F]

Think there could be some rather lively surface based storms today once we get some breaks appearing in the cloud and some strong insolation, some breaks appearing here now. The 00z Trappes (Paris) ascent sampled a rather unstable airmass above 800mb - with CAPE above 1000j/kg and high PWAT value of 39, the humid airmass across Sern England being sourced from Nern France today ...

... increasingly humid airmass is advecting NW across Sern England this morning with dew points of 16-17C already across SE England on latest obs, GFS shows dewp getting as high as 19C across SE England - so with temps reaching 24C we could see some decent CAPE values reaching 1000 j/kg and cloud tops may get as high as 35000ft looking at forecast soundings allowing some strong storms to develop, with main threat being high-extreme spot totals, hail and frequent cg lightning.

[MAF]

...................with main threat being high-extreme spot totals, hail and frequent GC lightning.

sounds good to me Nick :lol:

i see the new roof is been employed at Wimbledon this morning. wonder if they use the NW 5 minute radar

[SteveB]

Think there could be some rather lively surface based storms today once we get some breaks appearing in the cloud and some strong insolation, some breaks appearing here now. The 00z Trappes (Paris) ascent sampled a rather unstable airmass above 800mb - with CAPE above 1000j/kg and high PWAT value of 39, the humid airmass across Sern England being sourced from Nern France today ...

... increasingly humid airmass is advecting NW across Sern England this morning with dew points of 16-17C already across SE England on latest obs, GFS shows dewp as high as 19C across SE England - so with temps reaching 24C would could see some decent CAPE values and cloud tops may get as high as 35000ft allowing some strong storms to develop, with main threat being high-extreme spot totals, hail and frequent cg lightning.

Where is the prime area for these storms Nick, and will this area of rain stretching across Southern England inhibit storm development?.

[MAF]

dont forget the lightning detector

http://www.netweather.tv/index.cgi?action=lightning;sess=

[Nick F]

Where is the prime area for these storms Nick, and will this area of rain stretching across Southern England inhibit storm development?.

Yes, the cloud could hamper surface based storms roughly N of the S Midlands, but satellite shows some clearer skies to the south of the band of thundery rain spreading slowly N, so southern counties up into the S Midlands could see some strong and slow-moving sfc based stoms develop inland - Wimbledon and London could be at risk of a torrential downpour.

[SteveB]

Yes, the cloud could hamper surface based storms roughly N of the S Midlands, but satellite shows some clearer skies to the south of the band of thundery rain spreading slowly N, so southern counties could see some strong and slow-moving sfc based stoms develop inland - Wimbledon and London could be at risk of a torrential downpour.

So as soon as this band of rain clear North, then later today anywhere South of it could see storms develop later this afternoon/ Evening?.

[Karen Ann]

I have to stay despite the storm overnight and the continuing rain this morning tis very muggy here still. Just got out the shower and feel sticky already!

[cyclonic happiness]

Nice looking band of showers just popped up to the east of Brum http://www.metoffice.gov.uk/weather/uk/radar/

[Coast]

Woke at 3.30 am to the sound of distant rumbles and high level lightning. Guesstimate it was out in the Channel somewhere but couldn't get my head around it at that time of day!

Gotta love ESTOFEX for today: :lol:

'Broadly speaken, thunderstorms are forecast from Ireland to the Black Sea and from Poland to Sicily. We don't want to keep the outlook that short and hence focus on regions, where thunderstorm coverage and attendant flash flood risk ought to be enhanced. It also makes no sense to concentrate on the paths of the 'omnious blobs' in the QPF field of GFS, the result of a failure of the convective parameterization scheme, which does not handle the release of latent heat in a correct way, producing artificial storm clusters, which also affect the mass flux and therefore causes shear and QPF maxima. As far as possible we basically stick with the WRF solution to avoid that problem but keep their calculations in mind, which occured mainly over E-Europe. For the rest of the outlook we once again split the huge forecast area into smaller regions, to keep an overview:

... SW-UK, CNTRL/N/NE-France and extreme SW-Germany...

The main story at mid/upper levels is a gradually northward sliding trough, weakening during the forecast and forcing a weak front (most prominent in moisture fields) to the east/northeast. The front itself loses strength, so its circulation ought to weaken betimes. Nevertheless it will be the focus for scattered to widespread initiation as atmosphere is weakly capped and humid with surface dewpoints in the mid-tens. The shape of the W-E aligned upper trough favors some mid-/upper divergence due to a departing speed max over Ireland, so current model solution of ongoing thunderstorm activity over the English Channel and SW-UK during the morning hours is not unrealistic. This cluster ought to get fed by moist and warm air, so it will probably keep its strength over SW-UK with heavy rain/flash flooding being the main risk. Over NE-France, thunderstorms evolve during the morning hours in a very weakly sheared environment, so slow storm motion could result in locally heavy rain rates. Any cluster will slowly drift northwestwards and affect parts of S-UK during the afternoon/evening hours. A level-1 was introduced, where excessive rainfall is possible, probably maximized over SW-UK.'

and UKASF:

Regions Affected

Southwest England, Channel Islands, Central Southern England, Southeast England, East Anglia, The Midlands, Wales, Replublic Of Ireland (Extreme southern areas of Northern England, West Cornwall, Scilly Isles and Northern Ireland are also included in the WATCH)

Synopsis

Heavy thundery rain will continue across south Wales, Devon, Somerset and parts of southern England during the early hours of Friday morning - due to the state of the air mass across these areas, thundery activity is likely to be sustained for the rest of the night. A band of thunderstorms will cross the English Channel during the early hours, being fed by a warm and moist air mass, and as a result is not expected to weaken significantly during the Channel crossing. Due to the unstable condition of the atmosphere and a moist humid air mass, we are likely to see development of thunderstorms becoming more prominent during the morning daytime hours. Local flooding may present a problem across the West Country and south Wales for a time, primarily due to persistent torrential downpours. A trough aligned NW-SE from Wales down to SE England, will allow further development of thunderstorms during the day on Friday - the trough is expected to weaken, and this may restrict thunderstorm development across eastern areas, however sufficient risk remains for this area to be included in the THUNDERSTORM area of the forecast. Hail can be expected with many of the storms. A weak trough is expected to develop across the Republic of Ireland and this is likely to produce heavy showers and thunderstorms as a result of daytime heating. Thunderstorms are expected to become more scattered during the evening hours and slowly decay, although locally thunderstorms are expected to persist across central areas of England for much of the evening thanks to the favourable environment. We will continue to monitor the situation and further updates may be issued if required.

[Lynxus]

Obsolutely nothing here.

Just grey skies. and humid.

Looking at the rainfall and sat images, it appears to be dying off. Theres barely any sferics also.

Whats going on?

The metoffice are making out that armourgeddon is on its way but to me it looks like i may get some drizzle.

[Coast]

and still there at 18.00 hrs?

From IOW station, TStorm in Northern France heading this way?

*** NexStorm TRAC Report generated 26/06/2009 08:11:31

Tracking 1 thunderstorms

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Thunderstorm ID Q-1844 detected 05:50

Storm location bearing 121.9 dgr distance 206 mi

Last recorded activity 08:10

Intensity class Weak

Intensity trend Weakening

Current strikerate 1/minute

Peak strikerate 12/minute

Total recorded strikes 4521

Cloud-Ground strikes 2425 - 53.64%

Intracloud strikes 2096 - 46.36%

-- Strike type distribution --

Positive Cloud-Ground [+CG] 207 - 4.58%

Negative Cloud-Ground [-CG] 2218 - 49.06%

Positive Intracloud [+IC] 1433 - 31.70%

Negative Intracloud [-IC] 663 - 14.66%

-------------------------------------------------------

*** TRAC Report end - NexStorm V1.6.0.2553:PCI

Edited June 26, 2009 by Coast