Convective Outlook

[coldfingers]

Southampton showing a 60 knot gust at about 11:25 am. that is 69 mph.

Check out http://www.sotonmet.co.uk/

Click on more details to check history graph.

Edited November 22, 2009 by coldfingers

[dave48]

ESTOFEX forecast gives yet another level 1 for parts of the UK, full forecast below.

http://www.estofex.org/

It's mainly for severe wind gusts and a small chance of tornadoes.

Lightning activity looks unlikely.

[Coast]

ESTOFEX forecast gives yet another level 1 for parts of the UK, full forecast below.

http://www.estofex.org/

It's mainly for severe wind gusts and a small chance of tornadoes. Lightning activity looks unlikely.

I'll take that!!!

... United Kingdom ...

The forecast remains more complex for parts of UK during the passage of the developing trough. Models saw-saw in respect of BL moisture content and attendant CAPE, but overall potential for stronger updrafts looks better and better for each run, so we decided to include a level 1 for severe wind gusts and isolated tornadoes, but no thunderstorm area was yet included. Highest chances for deep convection probably exist along the SW coast of UK and beneath the coldest mid-levels over Wales and eastwards.

and this too!!!!

TORNADO WATCH 2009/012

A TORRO TORNADO WATCH has been issued at 23:45GMT on Sunday 22nd November 2009

Valid from/until: 03:00- 17:00GMT on Monday 23rd November 2009 for the following regions

Parts of (see map)

SW England Cent S & SE England Midlands E Anglia Mid and South Wales Channel Islands

Southern parts of Eire

THREATS

Tornadoes; wind gusts to 65-70mph; hail 10-15mm diameter; isolated CG lightning

DISCUSSION

A rather complex frontal wave (probably comprised of several smaller waves) will cross the region later tonight and through Monday, with a cold front (perhaps 2 cold fronts) moving south-eastwards through Monday. Models simulate instability and some convection in several locations around the wave, including along the leading edge of the moisture plume/warm front; within the moisture plume; and along the cold front(s). Deep layer shear will be sufficient for cell rotation/mesocyclones, with the flow veering from SW at surface to WNW by around 500 hPa). Low level shear will also be rather strong (850 hPa winds at 60 knots atop 25-30 knot surface winds, with a slight veering). Low-level mesocyclones may develop in any stronger, deeper cells, whilst along the cold front, misocyclones are possible. This complex combination brings a risk of severe wind gusts, along with a few tornadoes. Due to the uncertainty as to the mode(s) of convection in this case, it is hard to ascertain the potential strength of any tornadoes which may develop...however, the shear is sufficient that given any stronger cell development, a stronger tornado (T4+) is possible.

Definitely worth keeping an eye on the complexities of todays convective weather!

[dogs32]

we have had torrential rain on and off since 5.am...

A few roads being reported flooded.

The rain here currently is very heavy with squally winds wouldnt be surprised to get a few cracks of thunder today

looks nasty down in DEVON

Edited November 23, 2009 by dogs32

[weatherobsuk]

From 11am-1pm it has been eerily Dark here in South Manchester as this developing Low has been crossing East, bringing light-moderate rain. But as it must be moisture packed its blocked out any avaliable sunlight casting a twilight-like atmosphere for the past couple of hours.

All the houses in the street have had their lights on, although the street-lights didnt. I believe that they came on in Sheffield though. Even now a second batch of precipitation from this Low is developing and bringing yet more rain. TORRO got their warning box about 70 miles too far south, although they were correct on the developing Low-Waves Forecast.

[Coast]

A few sferics showing up around Nottingham now

[butler_son]

A few sferics showing up around Nottingham now

Oh...so that's what it was...

The weather had a funny spell about half an hour ago, certainly...

[Neilsouth]

Large anvil with mammatus to my south!!

[fujita5]

Violent squall just ripped through Brentwood - best winds I've seen for quite a while! Streams of leaves were being torn from trees and flying horizintally with sheets of rain. Most exciting weather moment of the year for me!

[Neilsouth]

I've just seen a funnel cloud to my south!!!! , going dark to my east now , surrounded by anvils

[Coast]

Violent squall just ripped through Brentwood - best winds I've seen for quite a while! Streams of leaves were being torn from trees and flying horizontally with sheets of rain. Most exciting weather moment of the year for me!

Same here in Benny Burgess Hill! Only gusting to around 30 mph according to local Wx but looks more with all those leaves buzzing around in a circle in the air. Can I pretend it was a brief tornado?

More to come?

[dave48]

The thunderstorms currently moving through the south east need to be watched very closely, rotation within the cloud is extremly likely as just confirmed by a funnel report, they may well take on supercellular characteristics if they haven't already. Strong chance of more funnels and even a tornado.

[Neilsouth]

The thunderstorms currently moving through the south east need to be watched very closely, rotation within the cloud is extremly likely as just confirmed by a funnel report, they may well take on supercellular characteristics if they haven't already. Strong chance of more funnels and even a tornado.

It certainly looked a nasty storm , lots of mammatus... Funnel Cloud... Very strong squall with it aswell

[fujita5]

To be honest I wouldn't be surprised if there was a tornado report from somewhere very close to here (Great Warley, Brentwood). The wind was unusually strong and was certainly at least double the 30mph reported in the area. Also it was sustained for 30 seconds or so rather than gusty and seemed to shift in direction during that time. I was looking out of a window in my offices and the leaves initially were blowing from L to R before slowly turning so they were head on. The roof was creaking and there was a very loud rushing sound, although this is most likely due to the nearby trees.

I haven't experienced winds of that strength for several years, actually very glad I wasn't outside!

[maidstone weather]

typical!

i seriously am in the wrong place

[dave48]

It certainly looked a nasty storm , lots of mammatus... Funnel Cloud... Very strong squall with it aswell

The mammatus indicate a strong updraft was or is present, which again suggests they could be very strong cells, the radar returns are really impressive, potentially LT supercells? I think they might be.

[Neilsouth]

BOOM! , the storms are moving through so quick though... blink and its gone

[dave48]

Shouldn't jump to conclusions regarding the likelihood of there being tornadoes in these cells, however the conditions are certainly there. The cells toward the SE have formed into a line so to me, it sounds like a squall type feature has setup over this region, which would increase wind strength considerably. Looking closer there is now a strong core within that line, so anyone underneath it, will probably be experiencing very strong winds and some decent sized hail.

Indeed, I would be interested to see just how big the hail is, the Larkhill sounding shows a significant dry air intrusion, but it is quite high up, about 500mb. There is a small one at about 700mb, but that combined with a strong rotating updraft might be able to produce some larger hail.

[Coast]

Coast you sad old git - desperately watching the lines of fast moving clouds out over the Channel, imagining every bit of scud is actually starting to rotate and could form a funnel if I turn away! Sorry folks, I must be losing it today!

Edit: Nice radar and sferic reutrns along the SE coast around Kent now.

[Neilsouth]

Well i was well chuffed to see a funnel cloud! , haven't seen a tornado for years though

[BrickFielder]

Unconfirmed reports of a tornado near Derby today.

[Coast]

TORNADO is believed to have hit Derby this afternoon.

Heavy winds and gusty weather hit Littleover at about 1.30pm today, striking Dennis Close, Leslie Close and Matthew Way. Firefighters said they had been called out to the area and the Met Office has confirmed the conditions were in place for tornadic activity.

www.thisisderbyshire.co.uk

Here: maps.google.co.uk

Tornado strike damages buildings

Dozens of homes in Derbyshire have been damaged by what is believed to have been a tornado.

Garage doors and roof tiles were ripped off properties in the Dennis Close and Haven Baulk Avenue areas of Littleover just after 1330 GMT. One eyewitness described being in the area as, "like driving into a washing machine".

The emergency services are now inspecting nearby buildings to make sure they are safe. There are no reports of any injuries.

news.bbc.co.uk

13.00 hrs:

[Coast]

Also sad to report, about 5 miles away from my work:

In West Sussex, the van driver was killed today after being hit by a falling tree in Bramlands Lane, Woodmancote, near Henfield.

The man, in his 40s, was trapped in his vehicle. West Sussex Fire and Rescue Service and the Sussex Police helicopter attended the incident but the man was pronounced dead at the scene.

www.independent.co.uk

[fujita5]

I commented earlier on another thread about the shape of that cluster, seemed to organise very nicely around that time and stayed coherent as it passed out towards the North Sea. Be interesting to hear if any more touchdowns occurred.

[Coast]

Nothing from the usual sources for today, but starting to already shape up for tomorrow:

Hold onto your hats, round 2 is going to be interesting again!