Convective Weather Discussion UK

[Backtrack]

Having heavy hail showers atm!

[Jane Louise]

Sunshine and showers here today. One heavy shower included! The sky did look very stormy at one point I was hoping for a rumble of thunder, but no, there was nothing apart from rain lol

[Static Prevails]

Nothing at all here. One extremely light 'shower'.

[Arnie Pie]

[Had that shower pass over here a short while ago, accompanied by small-size hail on the leading edge and two rainbows! Nice! Kept my eyes on it for a fair while in the hope of seeing the odd flash of lightning, but I didn't, sadly.]

This afternoons clouds from Birmingham including the rainbows and some nice movement with some convection.......Well a little bit

Hope you enjoy

Edit; No funnel clouds, Anvils or spinning dicky bows in the following timelapse,,,,,just boring old clouds and a wicked tune

http://youtu.be/H8eF5kG1seM

Edited April 12, 2011 by windypants

[Thundery wintry showers]

Your locations seemed to dodge nearly all of the showers judging by that timelapse!

[Rob]

Had a convective shower here this afternoon.

[Coast]

Expecting I think is overstatement - but it did appear that there were going to be some ingredients around for thunderstorms - some moisture, decent dew points, a cold front, increasing lapse rates...indeed, there was a lot of CIN brought about by the HP to our south, but some ingredients after 6 months of naff all will start some discussion, lol

Indeed, there have been a few convective bits starting up at different places around the UK - odd sferic here and there.

More than I thought would happen looking at the info available in the morning, so potential for the coming season eh?

[Harry]

More than I thought would happen looking at the info available in the morning, so potential for the coming season eh?

I really hope so Coast! I don't think it could be worse than last year for my location - just 4 thunder days in an ENTIRE YEAR, compared to the average 21 events over 15 days last year!!

Some areas did better than that, especially some of the places that are less likely to catch storms - such as the NE which iirc had a relatively good year.

Fingers crossed - am hoping for a typical summer I remember growing up - a few pokey night time plume storms, with rashes of daytime storms where you can get 4 or more storms within an afternoon

Edited April 12, 2011 by Harry

[Thundery wintry showers]

You are right, Cleadon in Tyne and Wear had 8 thunder-days last year which is about average for that area of the country, although three of them happened in November!

[Mesoscale]

I really hope so Coast! I don't think it could be worse than last year for my location - just 4 thunder days in an ENTIRE YEAR, compared to the average 21 events over 15 days last year!!

Some areas did better than that, especially some of the places that are less likely to catch storms - such as the NE which iirc had a relatively good year.

Fingers crossed - am hoping for a typical summer I remember growing up - a few pokey night time plume storms, with rashes of daytime storms where you can get 4 or more storms within an afternoon

We only had 2 days where thunder could be heard last year!!! we can all hope for this year though!

Edited April 13, 2011 by Mesoscale

[vortex_liam]

Alantic is doing its thing, could make something intresting although it would probally be in the north!

[camiscool]

Has anyone noticed those sharp showers ahead of the main band today?

[Hughsey]

Has anyone noticed those sharp showers ahead of the main band today?

yeh. had a rather heavy shower for 5 minutes or so at lunchtime but dried up out here now.

[camiscool]

sorry if this is a bit off topic, but behind the main band a very heavy area of precipitation is starting to develop. If this starts to move north we could catch it.

[Costa Del Fal]

sorry if this is a bit off topic, but behind the main band a very heavy area of precipitation is starting to develop. If this starts to move north we could catch it.

The rain will fizzle out and move away very soon and will not affect more of the UK than it is now.

[Stuart]

Long way off yet we may see some storms around the uk in under 15 days time :lol:

[Hughsey]

Long way off yet we may see some storms around the uk in under 15 days time :lol:

i agree lots of storm potential cropping up on the GFS in 5+ days time or so but unfortunately it wont stay that way id imagine.

[Coast]

i agree lots of storm potential cropping up on the GFS in 5+ days time or so but unfortunately it wont stay that way id imagine.

:lol: Not for Stuart yet again!

[Stuart]

Thanks Coast you now makeing me

[Hughsey]

:lol: Not for Stuart yet again!

haha, sorry coast im a complete amuteur and so those charts dont really mean much to me, is the london one good for storms?? the only thing that makes much sense to me on there is the lifting index which does look good for SE, Aberdeen one not so good lol, unlucky Stuart.

[Coast]

haha, sorry coast im a complete amuteur and so those charts dont really mean much to me, is the london one good for storms?? the only thing that makes much sense to me on there is the lifting index which does look good for SE, Aberdeen one not so good lol, unlucky Stuart.

Me too! I think you have the general idea of things that may mean there are possibilities later on. But this far away its a very rough guide not a forecast.

[Hughsey]

Me too! I think you have the general idea of things that may mean there are possibilities later on. But this far away its a very rough guide not a forecast.

ah ok cheers and yeah the charts will probably say something completely different in next couple of days but fingers crossed we will see some Tstorms soon

[Harry]

ah ok cheers and yeah the charts will probably say something completely different in next couple of days but fingers crossed we will see some Tstorms soon

With the influence of Low pressure quite limited and the nearby High likely to cause a high level of cloud cover, I think the opportunities in the coming week for home grown storms looks fairly limited. I think our best bet is if we get a plume setup materialise, of which the charts are pointing towards with the ECM and GFS models in rough agreement. GFS however, is one of the most erratic weather models particularly in respect of storm chances, which is what Coast's charts above depict. In literally one model run, GFS can change from high risk of storms, to no risk, and then back again. The orange bars at the bottom however I find interesting and relatively promising - lifted index (LI) is negative for a few days which indicates a more unstable atmosphere...this is common in plume setups and promising when considering convective possibilities. CAPE is also looking promising (I cant make this out from Coast's charts but can viewed on the main GFS models available on here)

Plumes however are notoriously tricky to nail down and to get a plume materialise, you need a relatively static setup to allow the moisture to advect and the air to become unstable on it's way northwards from Spain/France/N Africa.

The key to a proper, classic Spanish plume is explained in a handy and beautifully written Nick Finnis special, which can be found http://forum.netweather.tv/topic/29497-a-guide-to-uk-thunderstorm-setups/. Crucially, we need a relatively warm feed of moisture from the Med (our mini equivalent of the Gulf of Mexico) and/or the Bay of Biscay, and a dry feed of air to ascend the Spanish plateau to sit nicely like a giant lid over the feed of moist air at lower altitudes. This is like an atmospheric powder keg, whereby the air turns increasingly unstable, with the bouyant moist air trying to rise but the dry air surpressing it). With modest heating from the sun, the dry lid can break and in turn generate large, powerful thunderstorms, ranging from pokey single cells, to supercells and mesoscale convective systems (MCS), large mass of thunderstorms clumped together.

At the moment, the models (GFS and ECM) are pointing to this setup materialising. Our friend, the erratic GFS, is suggesting at the moment several days in April (more so in England and Wales at the moment) where thunderstorms are possible.

I would NEVER advocate trusting GFS until a day, two at the very max, in advance. If models are jointly agreed (as at present), it is looking good!!

Edited April 14, 2011 by Harry

[Hughsey]

With the influence of Low pressure quite limited and the nearby High likely to cause a high level of cloud cover, I think the opportunities in the coming week for home grown storms looks fairly limited. I think our best bet is if we get a plume setup materialise, of which the charts are pointing towards with the ECM and GFS models in rough agreement. GFS however, is one of the most erratic weather models particularly in respect of storm chances, which is what Coast's charts above depict. In literally one model run, GFS can change from high risk of storms, to no risk, and then back again. The orange bars at the bottom however I find interesting and relatively promising - lifted index (LI) is negative for a few days which indicates a more unstable atmosphere...this is common in plume setups and promising when considering convective possibilities. CAPE is also looking promising (I cant make this out from Coast's charts but can viewed on the main GFS models available on here)

Plumes however are notoriously tricky to nail down and to get a plume materialise, you need a relatively static setup to allow the moisture to advect and the air to become unstable on it's way northwards from Spain/France/N Africa.

The key to a proper, classic Spanish plume is explained in a handy and beautifully written Nick Finnis special, which can be found http://forum.netweat...rstorm-setups/. Crucially, we need a relatively warm feed of moisture from the Med (our mini equivalent of the Gulf of Mexico) and/or the Bay of Biscay, and a dry feed of air to ascend the Spanish plateau to sit nicely like a giant lid over the feed of moist air at lower altitudes. This is like an atmospheric powder keg, whereby the air turns increasingly unstable, with the bouyant moist air trying to rise but the dry air surpressing it). With modest heating from the sun, the dry lid can break and in turn generate large, powerful thunderstorms, ranging from pokey single cells, to supercells and mesoscale convective systems (MCS), large mass of thunderstorms clumped together.

At the moment, the models (GFS and ECM) are pointing to this setup materialising. Our friend, the erratic GFS, is suggesting at the moment several days in April (more so in England and Wales at the moment) where thunderstorms are possible.

I would NEVER advocate trusting GFS until a day, two at the very max, in advance. If models are jointly agreed (as at present), it is looking good!!

wow thanks harry great post, was really helpful. and the gfs has never seemed very reliable when I have been following it so certainly wont get too excited by it but yes things are looking fairly good at the moment so hopefully it will be the same picture on the weekend. and sorry I just voted negative for your post, meant to click positive lol, dont think I can change it now but thanks again, very useful.

[MP-R]

Apologies for going slightly off topic but any idea why the wetterzentrale lightning archives stop at 11th December 2007 or is it just with me? I can't seem to access anything more recent than that. Thanks.