7 July 2011 - Storm/convective Forecast, Discussion And Reports

[Lancashire Lass]

Lots of lightening strikes showing up on the radar. Nothing here for a while. Maybe I'll get lucky with the next approaching band of rain.

[Alex95]

The Yorkshire Dales look nice at the moment! I doubt it'll reach this far North, but it is exhibiting the characteristics of a weak multicell storm.

[Snow free zone]

That is a BEAST in N Lanchasire. Lucky people up there....

Yes it is very slow moving as well, could be some large localised rainfall totals in there somewhere.

[peterf]

christ i hpoe this next one weakens instead of gaining,looks awesome.

[Katherine]

What's the best URL for storm activity mapping and rainfall radar?

[Darren Bown]

Yes it is very slow moving as well, could be some large localised rainfall totals in there somewhere.

Dont wish that, it might die out as quickly as it formed!

[Eabie]

Nothing happened here yet except (as usual) light showers.

[P-M]

christ i hpoe this next one weakens instead of gaining,looks awesome.

NOOOOO Peter you want it to intensify And then double in size when it gets 10 miles south of Conset

[Stuart]

Last Updated: 20:05 Thursday, 7th July 2011

Valid: 06:00 Friday, 8th July 2011 - 05:59 Saturday, 9th July 2011

Areas Affected:

Majority of the British Isles

Synopsis:

A slow moving area of low pressure both at surface and upper levels is forecast to remain dominant across the UK during the course of Friday. Frontal systems and associated troughs are forecast to affect many areas, along with various zones of PVA. The highly cyclonic environment is forecast to continue to combine with surface heating during the day on Friday to create a widespread convective situation across many parts.

Discussion:

A large area of the UK is at risk of convective activity during the day. Various forecast soundings from Scotland, Ireland, Wales and England all signal the threat of convective instability occurring with surface temperatures ranging between 14C and 17C and Td’s in the range of 8C to 10C. Diurnal heating will combine with the area of low pressure to create a completely unstable atmosphere across many areas and scattered heavy showers and a few thunderstorms are possible almost anywhere across the UK during the course of Friday.

However, of particularly concern is across parts of England and Wales. The centre of tomorrow’s low pressure is expected to be across the majority of Wales and there is forecast to be an occlusion, which is likely to act as a focal point for heavy showers, thunderstorms and perhaps more organised heavy precipitation. The latest UKMO MESO and NAE models are signalling the threat of some heavy and potentially thundery downpours developing across Wales, parts of the Midlands and up into Northern England during the day. Some large rainfall totals are possible across these areas. Forecast atmospheric soundings across these areas are signalling in excess of 600 to 700j/kg of SBCAPE and around 400 to 500j/kg of MLCAPE, with LI’s near -2. There is a general lack of DLS and LLS given close proximity to the low centre, despite 0 to 6km DLS ranging between 20KT and 25KT. Despite this lack of shear, the depth of instability which is likely to be over 25,000ft to 30,000ft and the predicted CAPE is still likely to lead to some very heavy and thundery downpours, bringing gusty winds, torrential rainfall and a threat of hail.

The other zone of interest is across parts of the Midlands, Central-Southern and South-east England. An occlusion is forecast to bring a zone of more extensive frontal cloud and PPN for a time during the morning, but solar input is then expected by late morning and into the afternoon as cloud amounts become more broken. Forecast soundings are again signalling potentially up to 500 to 600j/kg of SBCAPE across the highlighted area. However, there is a significant risk of a greater LLS and DLS due to the location of the low pressure. Forecasted 0 to 6km DLS is between 25KT and 35KT, with perhaps over 20KT to 25KT of 0-1km LLS. There is also forecast to be some helicity as well, given variations in wind direction within the lower layers of the atmosphere and perhaps 100 to 150m2/s2 of helicity. A combination of the deep instability, quite high amounts of DLS and LLS and helicity may well lead to the threat of some well organised heavy showers and thunderstorms during the late morning and into the afternoon. There is a risk of funnel clouds and perhaps an isolated tornado, particularly given low LCL heights. Some medium sized hail could occur, along with the threat of some particularly strong wind gusts.

In summary another very highly convective day for a large portion of the UK, but parts of England and Wales in particular are at risk of experiencing some noteworthy convection and thunderstorm activity.

http://www.ukasf.co.uk/storm-forecasts/33

[Purplepixii]

That large amount of rain in the channel sure is sitting there! Anyone down on the south coast know if it is gaining intensity or of a stormy nature? Doesn't seem to be moving at all!

No storms here but sky is rather impressive! It's gone quite dark and there seem to be a multitude of different cloud types scudding across the sky - some slow (higher up) and some fast (nearer the ground) and of varying colours and shapes. Oh, and as I type it's just started raining again!

I did think that I heard thunder earlier but when I looked out of the window it was just one of the neighbours putting out his wheely bin - those damn things give me so many false alarms that I'm tempted to tie cowbells on them all so they don't get my hopes up!

:ph34r:

[Darren Bown]

No storms here but sky is rather impressive! It's gone quite dark and there seem to be a multitude of different cloud types scudding across the sky - some slow (higher up) and some fast (nearer the ground) and of varying colours and shapes. Oh, and as I type it's just started raining again!

I did think that I heard thunder earlier but when I looked out of the window it was just one of the neighbours putting out his wheely bin - those damn things give me so many false alarms that I'm tempted to tie cowbells on them all so they don't get my hopes up!

:ph34r:

I don't see that rain in the channel as being particularly heavy.

[tomp456]

What's the best URL for storm activity mapping and rainfall radar?

Well for rainfall its netweathers own radar...(if you poor and can't afford it google 'met office invent')

Storm activity...lightning?

btw im now following you on twitter

http://www.isleofwig..._storm_data.htm

Edited July 7, 2011 by tomp456

[peterf]

NOOOOO Peter you want it to intensify And then double in size when it gets 10 miles south of Conset

not today, as got to round the young pullets up and lock them in lol.buggars wont go in till it starts getting dark.

[P-M]

not today, as got to round the young pullets up and lock them in lol.buggars wont go in till it starts getting dark.

How many you got like? lol

[peterf]

How many you got like? lol

20 or so and ducks,as off to lock them in now.that cell looks like a bullseye lol.

[paul m]

Typical further north getting the action again.. Dont you think you have had enough

[Paul]

What's the best URL for storm activity mapping and rainfall radar?

For radar you have our own one available (although it is paid for @ £3.49 a month or £23.95 a year), it also includes lightning detection:

http://www.netweather.tv/index.cgi?action=other;type=radar;sess=

For lightning on it's own and freely, I'm obviously biased but our strikestar detector combines more than 30 detectors to give the most accurate picture possible:

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

[P-M]

Typical further north getting the action again.. Dont you think you have had enough

lol Howay man Paul it's usually us up here moaning that we don't get enough, but granted this summer so far has been great for the electric stuff! I feel your frustration bud but if it's any help that cell will probably have died a long death by the time it reaches Tyneside!

[paul m]

lol Howay man Paul it's usually us up here moaning that we don't get enough, but granted this summer so far has been great for the electric stuff! I feel your frustration bud but if it's any help that cell will probably have died a long death by the time it reaches Tyneside!

Its looking impressive at the moment

[P-M]

Its looking impressive at the moment

The one around Knaresborough and Boroughbridge looks like it's maintaining but the one just to the south of county Durham is slowly losing it's intensity and thats the one destined for Tyneside. Unlikely to start bumping up again IMO but you never know!

[Staffordshire]

Tommorow looks well... SEXY! I've been spoilt already today but looks like I could get more tommorow... Oh and paulym I have a feeling you will get your long awaited treat.

[tomp456]

Tommorow looks well... SEXY! I've been spoilt already today but looks like I could get more tommorow... Oh and paulym I have a feeling you will get your long awaited treat.

Some things in life are just not fair!

And that ^^ is one!

[P-M]

Tommorow looks well... SEXY! I've been spoilt already today but looks like I could get more tommorow... Oh and paulym I have a feeling you will get your long awaited treat.

Agreed, looks VERY unstable in places. The NE are just out of the warning zone according to ukasf but I am hopeful along with a big chunk of central UK...

[peterf]

done and dusted they all perched up now.looking like a hit for me here.

[P-M]

done and dusted they all perched up now.looking like a hit for me here.

Aye but looks like it's dying down a tad now and also appear to be moving more south to north rather than sw-ne like before. Is that just my eyes though!!