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

[Jane Louise]

A new thread for Tuesday

I think it's more favored for the Eastern side again .

Good luck all.

[Nick F]

Convective / Storm forecast - Issued 18/07/2011 22:30

Valid: 19/07/2011 06:00 - 20/07/2011 06:00

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

Synopsis

Slow moving upper/surface low across NE UK will maintain an unstable NW flow towards the eastern side of the UK during Tuesday, .

... CENTRAL and SERN SCOTLAND, E ENGLAND ...

Generally slack NW flow across UK will be characterised by steep lapse rates towards the eastern half of the UK, close to the upper low near the NE. So scattered diurnal thunderstorms are likely to develop aided by insolation and also wind convergence zones likely from SE Scotland down the eastern side of England. These convergence zones will likely be the focus for storm development and given light winds aloft and high precipitable water content of atmosphere (PWAT of 25mm+), any storms will likely be slow-moving with potential of releasing excessive rainfall - bringing risk of localised flooding. Also given light winds aloft, wind convergence and low LCLs ... funnels or even a brief weak tornado cannot be ruled out with stronger updrafts. Storms should die out after dark.

Issued by: Nick F - Forecaster for Netweather

Also can be found here: http://www.netweather.tv/index.cgi?action=convective;sess=

[Purplepixii]

There's the possibility of some storm action down here tomorrow but I won't hold my breath - the south isn't the storm hotspot it used to be

:blush:

[ZONE 51]

you know what, this is-for some a thundery summer and that comes after quite an active spring, remember 2010 in many areas had 0%..and yet another convective day today! we can't all be in the same boat at once, if you are not in tuesdays zone your turn will come(if you want storms!) its not over yet with more activity ahead.

-

anyway today is looking very good, if the sunshine is out and the towers are building then you could be in for some action and even if its cloudy, don't forget the breeding grounds-this is where an area builds the storm and this moves into a cloudy area that would not develop one. on monday it was cloudy then soon as the sun broke through then mountains grew quickly, on tuesday cold upper air and ground heating as well as convergence zones/lines are going to create a very high potential for activity, in fact it could be one of the best! on the eastern side and middle!

Edited July 19, 2011 by ElectricSnowStorm

[ZONE 51]

here is some GFS 18z charts

CAPE, upper temperatures at 500hpa in the afternoon, lifted index for the early evening, and surface temps and dew points for 3pm.

as you can see enough CAPE to break out some active downpours, and storms then generated from these later with lifted index showing unstable air as yellow and slightly unstable as light blue but enough is there!, sunshine is hot this time of the year and it heats the ground and rises the moisture to build the clouds, then we have winds meeting up yet helping pump up those cumulonimbus into huge thunderstorm clouds and the moisture amounts to be held and dropped would cause flash flooding, we have low pressure to the NE this is the driving force of our action.

Edited July 19, 2011 by ElectricSnowStorm

[P-M]

Just watched this morning's regional BBC weather forecast for NE England and Hannah says quote "look at this map it's like something from a Batman movie, bang bang bang see how the lightning breaks out over the region this afternoon with heavy slow moving and torrential showers" - fills me with hope really but we shall see!

[Lynxus]

Wow estofex looks lovely for the rest of the EU.

Today however looks good again for those who already have seen storms.

Once again however it looks like a minimal risk for here again. Booooo

Goodluck yall.

[Bluebreezer54]

The North East has certainly had more than its fair share of storms in recent weeks, and it looks as though they right in the zone again today. Good luck to all but with the forecast for 'severe' lets hope the flooding doesn't get too bad.

[Stuart]

Last Updated: 22:27 Monday, 18th July 2011

Valid: 00:00 Tuesday, 19th July 2011 - 23:59 Tuesday, 19th July 2011

Areas Affected:

Eastern Britain

Synopsis:

An area of low pressure centred over the North Sea will continue to slowly fill through the day, putting much of Britain in a north to northwesterly airstream with cold air aloft. Various surface troughs may develop and move through that flow during the day.

Discussion:

A slowly decaying vertically stacked area of low pressure will continue to provide a cold pool aloft with modestly cold 500mb temperatures of around -20C in eastern Britain. Areas of PVA will continue to provide extra lift across SE England during the afternoon enhancing the risk for convection. ELTs will be near -35C in a small region between the Wash and the Humber during the afternoon, overlapping moderate SBCAPE values in the region of 400-500j/kg giving this area the largest potential for lightning in any heavier showers. The low pressure area is very washed out and mixed throughout the atmosphere therefore there is almost no DLS or LLS so funnels are very unlikely, and really only possible in any localised convergence boundaries or topographically enhance lift

Main threats: Isolated heavy downpours and a few CGs

http://www.ukasf.co.uk/storm-forecasts/44

[Coast]

Wow estofex looks lovely for the rest of the EU.

Then we really should get together and do some chasing!

Storm Forecast

Valid: Tue 19 Jul 2011 06:00 to Wed 20 Jul 2011 06:00 UTC

Issued: Mon 18 Jul 2011 20:49

Forecaster: KOROSEC

SYNOPSIS

An unseasonably strong and negatively tilted large upper trough still dominates across W-CNTRL Europe while making a slow eastwards progress. The main feature today will be a powerful DCVA maximum traveling from S France into the northern Mediterranean. At surface, a large cyclone is placed over central Europe, moving slowly towards NE where another secondary low forms over N-CNTRL Italy. There are two cold fronts that will be the focus for severe storms today. One extending from Baltic states towards N Balkans and the second one associated with the upper disturbance crossing N-CNTRL Italy. Locally, intense severe storms (a few significant events possible) are expected.

DISCUSSION

A level 1 was also extended for possible isolated storms along the NE Alpine region where favorable shear/SREH seem supportive for some organized storms. Combined with several hundreds of MLCAPE and easterly LL wind field, a few storms with larger hail threat cannot be ruled out there. Scattered convective activity will result behind the upper cold core from NW Alps towards Benelux, mostly during the daytime/heating hours.

Forecaster: Chris

Last Updated: 22:27 Monday, 18th July 2011

Valid: 00:00 Tuesday, 19th July 2011 - 23:59 Tuesday, 19th July 2011

Areas Affected:

Eastern Britain

Synopsis:

An area of low pressure centred over the North Sea will continue to slowly fill through the day, putting much of Britain in a north to northwesterly airstream with cold air aloft. Various surface troughs may develop and move through that flow during the day.

Discussion:

A slowly decaying vertically stacked area of low pressure will continue to provide a cold pool aloft with modestly cold 500mb temperatures of around -20C in eastern Britain. Areas of PVA will continue to provide extra lift across SE England during the afternoon enhancing the risk for convection. ELTs will be near -35C in a small region between the Wash and the Humber during the afternoon, overlapping moderate SBCAPE values in the region of 400-500j/kg giving this area the largest potential for lightning in any heavier showers. The low pressure area is very washed out and mixed throughout the atmosphere therefore there is almost no DLS or LLS so funnels are very unlikely, and really only possible in any localised convergence boundaries or topographically enhance lift

Main threats: Isolated heavy downpours and a few CGs.

SkyWarn:

Severe Weather Risk: Moderate

More heavy and thundery showers for Scotland, and Eastern and Southern England through into Tuesday. Strong winds for western and northern coasts.

A lot of agreement on the East side of the country under consideration for today. I am particularly drawn to the feature over The Wash, somewhere in between Nottingham, Grimsby and Peterborough, moving out towards Skegness later?

[Staffordshire]

Let me have a guess who's going to get them... um Scotland and eastern England by anychance?

I'm holding out hope for Thursday...

Edited July 19, 2011 by Staffordshire

[Static Prevails]

Looking more promising for me today. I'm not really that far from the main risk zones, and the sun is making an appearance here.

[Stuart]

the sun is out here so it look promising after a bust on moday and last few days thiis could will be my last storm before I move

[Alex95]

Here we go again! I reckon the storms will be more likely around 10 miles inland today if a convergence line is involved. Often in these situations I see lightning to my west, but the storms take hours to move here, and when they do they die out. We'll see.

[Coast]

Dew points looking OK for this time of the day:

Bit of a way to go yet, but plenty of time and the sun is out currently.

[grab my graupel]

As it's sports day at my son's school, I'll be keeping my fingers crossed for some nice beefy showers

WRT any electrical activity, there appears to be only a slight for my region today.

[sunny scunny]

Not looking good at all here today after seeing my local forecast.Most of the showers were forecast to be at the coast with areas 20 mile or further inland remaining dry.Happens a lot with a NW wind

[Coast]

As it's sports day at my son's school, I'll be keeping my fingers crossed for some nice beefy showers

Avoiding the egg and spoon race eh Brian? :lol:

[Stuart]

just seeen the local weather forecast on bbc website there say storms later this afternoon and this evening :drunk:

[Lynxus]

Chilly and Grey here at the moment.

Im hoping to see something today as its is "possible" however i fear the fun will be mainly for the east.

Fingers crossed.

Goodluck yall.

[Hodgheg]

Wow theres some amazing towers allready going up today. Never seen anything like it.

[Guest]

Wow theres some amazing towers allready going up today. Never seen anything like it.

You're not wrong there, son.

I'm not massively hopeful of anything here today, simply because the risk is further east, so I think although we'll likely see a couple of heavy downpours, I doubt I'll hear thunder.

I think we're more likely to be the breeding ground here. <_<

One thing I am hopeful for though is the direction the showers will be moving in - NW to SE, or even N to S at times. A little different from other days when the east has been at risk, so could be a better set up here.

Edited July 19, 2011 by UKStorms

[Adi F]

I am not holding my breath for us down on the south coast, there maybe a small chance of something around 17/1800 hours but I don't think it will come to much.

[Walkinglad2013]

9.49 - Leeds = Massive cumulinumbus clouds and towers building over West Yorkshire to S and SW of Leeds city centre.

I have never seen anything like it in the UK - more similar to storms you would expect in the tropics

I expect thunderstorms here later on today! I think it may already be raining over the Wakefield area and Pennine regions.

There is some sunshine in between the unstable clouds.

I would estimate that the tops of the cloud are easily 28000 to 30 000 ft maybe higher in places!

Very interesting weather ahead I think!

[Guest]

Welcome! Nice to see another Yorkshire lad 'ere