2nd Aug 2011 - Storm/convective Forecast Discusion And Reports

[multi cellular thunderstorm]

Hi, my first post since moving to Nottingham.

It's so hot and humid i'm just not used to this up north! 26c here now and partly cloudy with some sun and only weak convection.

Looks like my old place of work up in Consett is getting a storm right now

Come on Nottingham show me what you can do!

[P-M]

Hi, my first post since moving to Nottingham.

It's so hot and humid i'm just not used to this up north! 26c here now and partly cloudy with some sun and only weak convection.

Looks like my old place of work up in Consett is getting a storm right now

Come on Nottingham show me what you can do!

Yes I am watching that from my west. Strange as the sky has gone quite milky in places and yes I agree about the humidity, it's killing me at work and with no air conditioning just makes things worse!

[Coast]

Might have been a nit of a mistake to go out on the bicycle at lunchtime - its really humid!

Small amount of sferics across Southern and Eastern France, I'm not expecting them to make any impact here today, but I'm still holding out for tomorrow for something.

[Noctilucid]

Afternoon all

Impressive high based downpour early this morning, currently there is towering cumulus rather getting its act together to my North East, most likely around the Brentwood/Chelmsford area.

[P-M]

From Tony Gilbert at UKWW:

Interesting thunderstorm just west of Newcastle ATM. Showing some signs of a sustained updraft!

I am watching it from my west and the sky looks pretty amazing like, just need it to hold out as this would be a direct hit! Good luck to you all who are storm starved, if I was God I would send some your way

[Wet'n'Dry]

Afternoon all

Impressive high based downpour early this morning, currently there is towering cumulus rather getting its act together to my North East, most likely around the Brentwood/Chelmsford area.

Afternoon, yes I can see them towering from my West to East. Milky skies otherwise and nothing to my South. The humidity is killing me so hopefully I'll get a drenching but somehow I doubt it

Edited August 2, 2011 by Wet'n'Dry

[Lancashire Lass]

Temperature has shot up since the sun burnt the cloud off. Currently 26c, dewpoint 19.c. Some good cloud formations and some hefty looking showers heading this way but nothing electric I don't think.

[P-M]

Deep thunder heard to my west now, distant but deep.

[Raidan]

If that mass coming up from the bay of biscay makes it to the uk what areas are likely to be effected?

[maxemoo]

Just read in The Sun that apparently it is set to reach 29c today and we could see 30c tomorrow. But "violent" thunderstorms will soon bring the spell to an end.

You never know. The Sun may be right for once!!!!!!!

[Coast]

You never know. The Sun may be right for once!!!!!!!

If they are, then they've probably got that from a real forecasters answer phone...... <_<

[Flash Elvis]

Afternoon, yes I can see them towering from my West to East. Milky skies otherwise and nothing to my South. The humidity is killing me so hopefully I'll get a drenching but somehow I doubt it

I can see them to my west...nothing happening around here...damn clouds !!!

That stuff going across Bay or Biscay looks like missing us unless winds shift to a more northerly direction

[Arnie Pie]

If they are, then they've probably got that from a real forecasters answer phone......

[topsweep1506]

Thunderstorm in Cramlington now rain not to heavy though just heard thunder on cam!

Torrential rain now

TONY

[VillagePlank]

Whilst we're all sitting around waiting ... today seems to be a day where surface heating is likely to be the trigger for storm generation. But how can we tell whether convection will kick off ...

Well, the physics is a little awkward, so I've made two charts for handy reference:

Lots of numbers. Handy.

Let's get the temperature and dew-point at the surface, first:

Taking the first chart the numbers down the left hand side are your dewpoints, the numbers across the top are temperatures. If you cross reference them - I'd say Temp=24C, DP=16C for Rochester which gives us the number 22C. Technically, this is an approximation of what is known as the Theta-W temperature, or, the wet-bulb equivalent potential temperature ...

If you look at the second chart you can see how much convective rain you'd expect from such a forecast. The answer is... none for Rochester. However, nudge up to Dp=17 and you'd expect convective rainfall. Actually, the convective initiation point is 22C but as we're measuring a point in time, the chances of it lasting long enough to make big clouds is slim.

This is for surface heating initiated convection - of course, you have to factor in all sorts of other stuff, too. As there's not too much 'other' stuff in the SE to trigger convection, I'd go for no home grown storms in Kent, today.

The linear relationship between theta-w and subsequent rainfall totals (ie storm initiation) is in the Relationship between surface conditions and subsequent rainfall in convective storms paper.

Edited August 2, 2011 by Sparticle

[P-M]

Thunderstorm in Cramlington now rain not to heavy though just heard thunder on cam!

Torrential rain now

TONY

That's the one that passed to the west of me, sky was black and heard 3 rumbles altogether, nothing major but rain was torrential for a time. A notch up from yesterday's mini one

[topsweep1506]

www.livestream.com/ecmlcam is the cam still really load thunder

[Carl46Wrexham]

If that mass coming up from the bay of biscay makes it to the uk what areas are likely to be effected?

Clue 1....Areas in part of the UK made up of the following letters T A S E (rearrange to get the answer).

Clue 2....The bleedin obvious ones!

[gottolovethisweather]

Whilst we're all sitting around waiting ... today seems to be a day where surface heating is likely to be the trigger for storm generation. But how can we tell whether convection will kick off ...

Well, the physics is a little awkward, so I've made two charts for handy reference:

Lots of numbers. Handy.

Let's get the temperature and dew-point at the surface, first:

Taking the first chart the numbers down the left hand side are your dewpoints, the numbers across the top are temperatures. If you cross reference them - I'd say Temp=24C, DP=16C for Rochester which gives us the number 22C. Technically, this is approximation of what is known as the Theta-W temperature, or, the wet-bulb equivalent potential temperature ...

If you look at the second chart you can see how much convective rain you'd expect from such a forecast. The answer is... none for Rochester. However, nudge up to Dp=17 and you'd expect convective rainfall.

This is for surface heating initiated convection - of course, you have to factor in all sorts of other stuff, too. As there's not too much 'other' stuff in the SE to trigger convection, I'd go for no home grown storms in Kent, today.

Well Thanks Sparticle.

I'm currently 26.4c, 18c Dp and that returns 24c Theta-W so maybe there is a chance for storm starved Newbury.

The temperature and associated Dp should hopefully continue to be favourable for a wee while yet, so who know.

Cheers

gottolovethisweather

Edited August 2, 2011 by gottolovethisweather

[topsweep1506]

Had a feeling that was gonna happen went offline lol

[Purplepixii]

www.livestream.com/ecmlcam is the cam still really load thunder

Says offline when I try it...

Apologies all for my earlier smut, I must learn to contain it in the future! Anyways, spent a few hours at the beach in Lee-on-Solent and it was overcast with a lovely gentle cool breeze coming off the sea. Just got home (which is only 3ish miles away as the crow flies) and it's hot, muggy and sticky - weatherstation says 24.3C / 54% humidity.

[Wet'n'Dry]

Clue 1....Areas in part of the UK made up of the following letters T A S E (rearrange to get the answer).

Clue 2....The bleedin obvious ones!

E A S T

I guess you're not happy

[Carl46Wrexham]

E A S T

I guess you're not happy

After having experienced the grand total of 1 thunder day over the past 14 months you could safely say...no I ain't!

[anvilhead]

i'm going to take a stab at some activity forming roughly around the salisbury area a bit later thisafternoon - dont take my forecasts seriousely whatever you do though!

[VillagePlank]

I'm currently 26.4c, 18c Dp and that returns 24c Theta-W so maybe there is a chance for storm starved Newbury.

The temperature and associated Dp should hopefully continue to be favourable for a wee while yet, so who know.

Convection should initiate and then, hopefully, unstable conditions indicated by LI should be able to take over and tap into that CAPE. But don't forget - it might well initiate above your head, but someone miles away might get the benefit!

Edited August 2, 2011 by Sparticle