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

[shuggee]

A new thread for a new day of potential showers of heavy rain with possibilities of something electrical. Enjoy.

[paul m]

It would be nice if tomorrow gave us a storm. I have to say that the showers today were welcome with the garden enjoying a soaking

[jello]

How is all this evening..

So what do you make of this on NI facebook page

Weather Advisory in force. Valid: Thurs 7th July 2011. Torrential showers & Thunderstorms. With unstable air across NI tomorrow, storms are likely to develop. These storms are likely to produce updrafts which could lead to large hail in excess of 2 - 3 cm. There is also a risk of funnel clouds & small tornadoes.

[Liam Ellis]

Thunderstorm to the North West of here - Many reports on Facebook but I think many's milking it! Just had another rumble now - heavy rain.

[paul m]

Thunderstorm to the North West of here - Many reports on Facebook but I think many's milking it! Just had another rumble now - heavy rain.

Just a few strikes showing up in your area at the moment

Edited July 6, 2011 by paul m

[Liam Ellis]

Just a few strikes showing up in your area at the moment

Still some flashing but now more towards the South West....although saying that strikes only around 1 ever 3/4 min.

[paul m]

I take it thats the storm showing up just off the west coast

[georgiedre]

Just had a thunderstorm here for the last 45 mins seems to be spinning around my area.n.w wales

[paul m]

Just had a thunderstorm here for the last 45 mins seems to be spinning around my area.n.w wales

Send it Leeds way please

[ZONE 51]

estofex storm forecast-not seen this posted

-

-zoomed a box here..

level1 just over the channel there!

think some level1 energy might just clip the SE later thursday just a risk..

[Biggin]

Line of heavy showers approaching W London, not electric tho atm.

[Coast]

level 1 just over the channel there!

Unfortunately I think that's where it may stay...... SkyWarn have a watch out:

SKYWARN UK SEVERE WEATHER WATCH #034

ISSUED: 1000UTC WEDNESDAY 6TH JULY 2011 (GJ/SM)

SKYWARN UK HAS ISSUED A SEVERE WEATHER WATCH FOR THE FOLLOWING REGIONS: CENTRAL SCOTLAND EASTERN SCOTLAND HIGHLANDS

IN EFFECT FROM 1000UTC WED 6TH UNTIL 2100 THUR 7TH JULY 2011

STALLED FRONTAL OCCLUSION FROM LOW PRESSURE SYSTEM OVER EIRE

THERE IS A POSSIBILITY OF SEVERE WEATHER AFFECTING THE INDICATED REGIONS IN THE TIME PERIOD SPECIFIED. THREATS WITHIN THIS WATCH INCLUDE, BUT ARE NOT LIMITED TO: HEAVY RAIN...PERSISTENT RAIN...FLOODING

DISCUSSION:

RADAR-DERIVED PRECIPITATION ACCUMULATIONS AND STATION REPORTS SUGGEST 20-30MM HAS ALREADY FALLEN OVER THE AREAS IN THIS WATCH, WITH GOOD MODEL AGREEMENT ON A FURTHER 40MM POSSIBLE IN THE PERIOD WITH UP TO 60MM LOCALLY. AN OCCLUSION IS STALLED OVER THE AREA, WITH OCCASIONALLY HEAVY BUT NEAR CONSTANT RAINFALL EXPECTED ON NOW SATURATED GROUND AND SWOLLEN RIVERS. SEPA HAVE ISSUED FLOOD ALERTS, THE MET OFFICE ALSO HAVE RAIN ALERTS IN EFFECT. THIS WATCH MAY BE UPDATED.

UKASF have the whole of the UK covered:

Forecaster: Chris

Last Updated: 21:27 Wednesday, 6th July 2011

Valid: 06:00 Thursday, 7th July 2011 - 05:59 Friday, 8th July 2011

Areas Affected:

Most of the British Isles

Synopsis:

A well developed, vertically stacked area of low pressure will be centred near western Ireland with various occlusions and upper troughs wrapped within it's circulation. Areas of positive vorticity advection combined with a broad upper trough axis centred near Ireland will combine for an unstable atmosphere across most of the British Isles through Thursday and into Friday.

Discussion:

A large area of convective potential is possible. In fact almost all areas across the British Isles have the potential of seeing at least a sharp shower/heavy downpour and rumble of thunder.

Main risk of thundery activity will likely set up near an upper trough/band of PVA that looks to push out of eastern Ireland during the morning and into western parts of Britain around midday before moving into eastern Britain during the afternoon. Midday SBCAPE values will likely be in the range of 600-800j/kg across NE Ireland before increasing to similar values into afternoon across Britain.

**An area of complication will be E/SE England as a band of cloud associated with an occluded front brings showery rain during the morning (some of which could be heavy). This will likely lose it's definition into the afternoon, giving way to some sunny spells which will allow for surface based convection to form. Therefore, thunder risk in this area will likely be a little later in the afternoon.

DLS values will be weak to modest in the range of 25-30kt, this may just be enough for some tilting updrafts, but storms will likely form lines/clusters anyway due to vorticity banding around the low. LLS shear looks best during the morning across northern Britain and Ireland so convergence funnels will be possible with showers there. (It should be noted that funnels are fairly common in this synoptic setup (vertically stacked lows) in Britain during the summer time, mainly due to the multitude of convergence boundariess available to showers. Funnel / tornado risk will be greatest along these convergence boundaries during the middle of the day in the N and W, however LLS becomes more favourable during the afternoon across SE England, so heavier showers (stronger updrafts) may bring the risk of funnels later in the afternoon to East Anglia and SE England.

In summary, it's a complicated broad convective set-up with a zone of heavier/thundery showers likely developing in the west during the morning and moving eastwards into the afternoon.

21st OWS also have the whole of the UK covered, that would be nice!

NOAA's aviation charts show activity down the East side:

CAPE not really there until the evening, ahead of the convergence line:

Some wind sheer around London though:

A lot of rain and blustery wind, maybe funnels in the SE?

Not so much a thunderstorm day, more a funnel/tornado/heavy rain kind of thing with potential for a bit of lightning later in the evening?

[VillagePlank]

Lots of potential out there, today, with a good chances for a lot of people methinks

[Adi F]

Today is oneday work prevents me chasing but saying that I am working in Kent, doing a product photo shoot so i will have my cameras with me. So hope to see something.

[Phelpsy]

Very cooler today, windy to, cloudscape just looks messy, not expecting anything here but good old rain. As long as it holds off an hour for my washing to dry im happy

[slinky1989]

Well I'm off to knebworth today for sonisphere festival, so I'm hoping to christ that it holds off until I can get my tent up! haha.

Very cool as Phelpsy said though. Thick blanket of cloud over us in swindon atm. Was really rather warm when a break in the cloud let some sun through for all of a minute

[Coast]

That wind shear should prove intersting around London later, Heathrow could see some 'go-arounds'! :unsure:

[Alex95]

I'd expect to start seeing those showers turn thundery in the next few hours - there's an awful lot of them on the radar, and they're heavy all ready! In fact, its looking pretty threatening here now. Today will be the 7th storm of 2011 if I get one!

[peterf]

the radar keeps throwing hissy fits this morning and it's all down to guess work now lol.

[Alex95]

the radar keeps throwing hissy fits this morning and it's all down to guess work now lol.

Yeah, 10:15 radar not working properly.

[peterf]

scrolling back it's all over the place.

looks like problems at the Sunderland site,bet them mackems have stripped the copper out lol.

[jello]

Hey all. hope ya get some storms today... Any possible in Northern Ireland. I hope so, Some lovely skies out there now clouds are already building.

[SteveB]

I can see today being another day of showers, nothing in the way of storms.

[Jane Louise]

Hey all. hope ya get some storms today... Any possible in Northern Ireland. I hope so, Some lovely skies out there now clouds are already building.

Thanks jello, Here's hoping!:good:It's looking ok for you today http://www.weathercommerce.net/

Hope you get to see something. Clouds look pretty good around here at the moment. Again I missed out yesterday I think Friday has more potential for me.

[peterf]

I can see today being another day of showers, nothing in the way of storms.

i cant see anything lol.