25th into 26th Aug 2011 - Storm/convective Forecast Discussion And Reports

[Jane Louise]

Ok, not looking so good tomorrow, but maybe a slight chance for all. good luck anyway . Always the optimist am I lol.

England

At the cyclonically sheared flank of the strong mid-level jet streak, latest models indicate weak warm air advection over eastern England. In the wake of a frontal wave, new showers and thunderstorms may develop during the day. Given moderate low-level vertical wind shear, some storms may produce weak tornadoes. The threat seems to be too low for a categorical risk.

http://www.estofex.org/

Sorry I can't seem to post up the map I must learn how to do it lol.

[Costa Del Fal]

Looks like another dry day here. Tonights rain which looks too miss here will probably leave a legacy of cloud preventing showers or storms near. Just 6mm of rain in the last month and August itself may leave with just 4mm should it rain no more here for August which after Friday looks quite possible.

Edited August 24, 2011 by Blizzards

[Harry]

Ok, not looking so good tomorrow, but maybe a slight chance for all. good luck anyway . Always the optimist am I lol.

England

At the cyclonically sheared flank of the strong mid-level jet streak, latest models indicate weak warm air advection over eastern England. In the wake of a frontal wave, new showers and thunderstorms may develop during the day. Given moderate low-level vertical wind shear, some storms may produce weak tornadoes. The threat seems to be too low for a categorical risk.

http://www.estofex.org/

Sorry I can't seem to post up the map I must learn how to do it lol.

A warm front is forecast to move in through tomorrow night and into Friday....how amazing would it be if it nudged further west allowing some very unstable air in.......keep imagining as while its possible the risk is about 0.1%

[AWD]

That estofex forecast looks pretty pants!! I was hoping for a bit better!!

Radar at watching it is tomorrow then!

[A.J]

It will be interesting to see how tonights rain/possible embedded thunder pans out..The first pulse of 'stuff' seems further west than progged by the models..by between 50-100 miles further west IMO

[Jane Louise]

Areas Affected:

MODERATE: N IRELAND

SLIGHT: IRELAND, S AND W BRITAIN

Synopsis:

A well developed area of low pressure will be centred just off the west coast of Ireland by midday allowing for some very cold air aloft to spill into Ireland during the afternoon. A complex, waving cold front will be draped across central parts of Britain bringing the focal point for some very heavy rain for parts of the risk area.

Discussion:

A complex weather day expected across the British Isles. Best broken down into 3 seperate events.

Event 1 (A line from W Dorset to the Humber from 0z through 10z) - A wave will develop along the cold front and push a pulse of heavy rain across this area, likely to produce some localised flooding in places with some rain totals in excess of 50mm (2 inches) possible in places. This will also carry some instablity with it and even overnight (indicated by the GFS) with 200-400j/kg of CAPE possible. Outflow from the heavy rain could also produce some gusty winds along the forward edge of it as it arrives in places, although nothing too severe is expected from straight line wind gusts.

Event 2 (A line from the IoW to Lincolnshire and E'ward across E Anglia/SE Eng from 7z through 15z) - A secondary wave will develope along the cold front allowing for another round of heavy rain. (This wave will not likely be as significant as the first, but could still produce rain totals in excess of 30mm (1 inch) in places.) It may also tap into some early surface heating, especially into parts of E Anglia and SE England during the afternoon, and this may enhance thunder potential there.

Event 3 (SW Britaind and Ireland - particularly N Ireland) Cold air aloft generated thunderstorms are expected. Very cold air aloft, with ELTs in the range of -45C along with CAPE values approaching 1000j/kg during the afternoon, especially across the northern half of Ireland will likely generate widespread showers and thunderstorms. Both DLS and LLS are weak through the afternoon, so most storms will be of the pulse variety bringing frequent CG lightning and some gusty winds and small hail (1-2cm), but severe weather potential is limited due to the likely pulse nature of the storms.

http://ukasf.co.uk/storm-forecasts/83

[The watcher]

2nd bite at the cherry for me tommorow then.

LI and Cape are perfect, DLS and LLS not so good, so pulse storms likely, but should be quite vigorous pulsers at that.

[Cheshire Freeze]

It will be interesting to see how tonights rain/possible embedded thunder pans out..The first pulse of 'stuff' seems further west than progged by the models..by between 50-100 miles further west IMO

Yes I was thinking that too

Edited August 24, 2011 by CreweCold

[Aaron]

Tonight might have some thunder mixed in. I'm hoping so, but I'm just looking forward to proper sustained rain of we don't miss out on it (which we probably won't but knowing this location..)

[PolarWarsaw]

Am i missing something in thinking that im in a good place to get rained on tonight. All forecasts maps, BBC rain radar and tonights radar seem to suggest we're in line for a couple of hours of heavy rain. But other close midlanders aren't so keen on the idea?

[Neilsouth]

http://www.camvista.com/watch-live-video/europe/germany_berlin_capital_city_streaming_webcam.html

THUNDERSTORM OVER BERLIN :D, click LIVE

[Costa Del Fal]

I agree, the Rain for tonight for now anyway seems much further West than thought and so here may at last see some proper rain.

[Raidan]

Might of just heard thunder not sure,Going to stick head out window for a few mins.

[Nick F]

Convective / Storm forecast - Issued 24/08/2011 23:30

Forecast Summary Map

Click for full size

Valid: 25/08/2011 00:00 - 26/08/2011 00:00

Headline: ... THERE IS A RISK OF THUNDERSTORMS FORECAST...

Synopsis

Deep upper trough extends south across Eire and Wern UK, driving a strong cyclonic SW flow across the British Isles. At the surface, an area of low pressure lies just to the W of Ireland with an occluding cold front moving E this evening across the UK becoming slow moving across England as a wave developing from SW moves NE across central England Thursday AM ... so by 12z Thurs front lies from Bournemouth - Scarborough with wave across Midlands. By 00z Fri, front clears E Anglia with a wrap-around occlusion moving N and E across Eire, Wales and SW England.

… SW ENGLAND, MIDLANDS, E and NE ENGLAND, …

Frontal wave moving up from SW England towards the Midlands tonight will see a return of warm/moist Tm air on warm side of slow moving frontal zone lying NE through England ... this increasingly moist air advecting NE beneath cooling upper air from the west may lead to some modest instability along/ahead of frontal zone tonight and Thurs morning with embbeded convection perhaps strong enough for a risk of isolated thunderstorms through Thursday morning. Given rather strong jet aloft parallel to the frontal zone (with 500mb winds of 55-65knts) and 40-50knts of deep layer shear indicated - convection/storms may organise into line segments bringing strong wind gusts and CG lightning along with torrential downpours with a risk of flash flooding. During Thursday morning and early afternoon, increasingly backed winds and low level shear across eastern England may enhance the risk for an isolated tornado where storms occur in wake of frontal wave in warm moist zone before cold front clears in the afternoon ... though lack of instability indicated suggests the risk is too low for a SLIGHT risk for now.

... EIRE, SW ENGLAND, WALES, N ENGLAND, SCOTLAND ...

Proximity of upper low/trough over Eire during the day will give steep lapse rates across N and W UK, allowing numerous heavy showers and thunderstorms to once again develop with surface heating across Eire and also across Wern and Nern mainland UK by the afternoon. Upper winds and deep layer shear will be weaker than further east, so storms are less likely to organise though hail, gusty winds, heavy rain and CG lightning are all possible with any storms.

Issued by: Nick F - Forecaster for Netweather

[Phil UK]

Cheers, Nick F. The rain from this front is just about knocking on Solihull/Birminghams doorstep. But if it does pull in the TM (Tropical Maritime) airflow then I think PPN intensification will occur.

And on that happy note, I'm off to bed. But have photo inventory set up just in case. (And with past set ups, usually meaning a waste of time! :-s )

Good luck. Goodnight.

Phil.

[Raidan]

Cool just noticed the storm risk for here has gone up,it was at 51% now its at 60% thats a good sign for Friday.

[dave reid]

Drivng from Bournemouth to Huddersfield in about an hr so hoping to see something exciting along the way. Will have the camera ready! Hoping for more than the other night when I drove to Portsmoth for frenchie. 3 distant bolts, all be it at the same time. BUST!

[sunny scunny]

Torrential rain at the moment

[Coast]

http://www.estofex.org/

Sorry I can't seem to post up the map I must learn how to do it lol.

http://ukasf.co.uk/storm-forecasts/83

[Coast]

Going to be a messy old day I think

CAPE builds through the day and peeks in the West of the country later in the afternoon:

Lifted index looks OK at that time:

KO index not indicating anything special:

Some convective cloud in Wales:

Shear also building nicely to the Western side

Convective rain just about anywhere and everywhere!

Plenty in the SE!

Chance of a funnel in North Wales or the North West - Cheshire/Merseyside?

Well I don't know what to make of today. Possibilities all down the Western side and Ireland, maybe some thunderstorms in Wales and a brief funnel further North than that. Rain all over and heavy as it moves East.

Then we have tomorrow.......

[SteveB]

Lots of heavy rain & showers around yesterday & last night, but not a sniff of any thunder or lightning.

Tday looks less likely to see any storms for my area, and tomorrow looks very messy.

[NO LONGER POSTING]

What I said I didn't get proven wrong then Nice little area of heavy rain moving towards me now

[VillagePlank]

[London/SE]

Here we go again. Another day with the now dreaded word 'thunder' in the forecast.

Doesn't look great for home grown storms - simply not enough moisture in the skew-T. For sure, there will be some but very few, I think:

There is CAPE/LI, and instability - it's not off the charts so can be believed. I imagine hail is quite possible, but strobe lightning - perhaps not.

The interest is overnight tonight. Low pressure in the Bay of Biscay and shunts an active system towards the SE - all models agree on this.

This is likely to produce excessive rainfall, and with it - potential for thunder. Back to the 1980's - middle of the night storms? Maybe.

IoW area looking at rainfall of 4 inches:

Edited August 25, 2011 by Sparticle

[Coast]

[London/SE]

The interest is overnight tonight. Cyclogenesis kicks off in the Bay of Biscay and shunts an active low pressure towards the SE - all models agree on this.

I won't kick off a thread about tomorrow until later in the day, but this could be the best chance for a while as things start to calm down a little after Saturday;

[Coast]

Already chucking it down here at work!