Storm & Convective Discussion - 16/07/15 onwards

[andymusic]

estofex are awfully quiet?????????????????????????????????????

[alexisj9]

Certainly warming and destabilising nicely over here in Limousin if you're going to share the same airmass in the UK. We've had ACAS on and off since early morning and it's currently 31c and incredibly humid feeling. LIG METAR says t-storms from 0200 well into tomorrow. Will keep you posted, and I look forward to reports of what the UK has to offer...

Seen some ac cas here too, along with some cumulus blowing in from the east sort of moving in the opposite direction from each other.

[stevofunnelcl]

They are firing up down south, but i'll hold off, since The English Channel is a classic storm killer.

The thunder may get sucked out, and we end up with outbreaks of thundery rain instead

[Dami]

estofex are awfully quiet?????????????????????????????????????

I noticed this aswell, but don't they do forecasts later in the evening?

[Mesoscale]

I noticed this aswell, but don't they do forecasts later in the evening?

They would of had tonight's one out yesterday, so I am guessing nobody has any really idea what's going on haha. 

[alexisj9]

Oh dear, I never knew it was a saying! :oops:Anyway, thanks and good luck to you, too!

Interesting! 71% here! Yeah, a thundery sky nearly makes my day, a rumble of thunder as well? That's enough to make me happy! Good luck!

87% here which is less than earlier 91%. Think it's cause the sun has finally cleared through that milky high cloud we had earlier.

[Phantom2]

things really starting to get going at a pace now over Britanny, fingers crossed the English channel doesn't weaken them ..looking forward to a light show here in Southeast Wales in the early hours, we shall see !

[UKSupercell]

I'll be up around 5-6 tomorrow to hit the M25 down to work in Surrey. And to think I'm spending all tomorrow outdoors operating machinery. Waterproofs it is. 

[Chris K]

Seen some ac cas here too, along with some cumulus blowing in from the east sort of moving in the opposite direction from each other.

I may be totally wrong and im sure someone will correct me if so, but i think Cumulus cloud will be influenced more by surface/low level wind direction. The ac cas will be moving with the winds aloft(mid-upper levels).

Edited August 12, 2015 by Chris K

[Methuselah]

87% here which is less than earlier 91%. Think it's cause the sun has finally cleared through that milky high cloud we had earlier.

The sun has just come-out here, too...28C tomorrow?

[East_England_Stormchaser91]

They are firing up down south, but i'll hold off, since The English Channel is a classic storm killer.

The thunder may get sucked out, and we end up with outbreaks of thundery rain instead

This year though it hasn't been bad. The epic Bournemouth storm this year on the 4th July started in the channel. It's all about what goes on above the boundary layer in elevated storm situations.

[Flash bang flash bang etc]

I would recommend buster hill as a good stop tonight. It's where I would be was I not drowning my storm sorrows with wine and seafood :-P

But seriously I want a good storm and I envy u lot!

Just looking at Google weather it only says showers over Butser. That would be completely wrong would it not? I hope so cos then the 'hot and sunny and no thunder' forecast for here is wrong too! :-D

[Evening thunder]

I bet the BBC graphics will be right and Egham will get walloped again now I'm in East Devon lol, while during my uni years I often watched storms hit home while Egham got very little.

 

Still, an interesting 24-36 hours to come and hopefully we have a good chance here, especially looking at the latest radar/lightning detection for Brittany!

[East_England_Stormchaser91]

I may be totally wrong and im sure someone will correct me if so, but i think Cumulus cloud will be influenced more by surface/low level wind direction. The ac cas will be moving with the winds aloft(mid-upper levels).

Yep, you're spot on there. Generally TCU, Altocumulus, AcCas and cumulonimbus will be moved by the upper winds at 300-500hpa.

[William Grimsley]

Eyes to the south is all I say! Have a good night everyone!

[Chris K]

Yep, you're spot on there. Generally TCU, Altocumulus, AcCas and cumulonimbus will be moved by the upper winds at 300-500hpa.

So my assumption is once storms become elevated, they will go in the direction of winds aloft too?

[Greeny]

A long shot I know but does anyone know where I can get weather charts for Mexico? Could be worth at least looking at some CAPE and LI charts.

A typical day here in Acapulco below although not always thunderstorms, I now know what its like to be in 24C dewpoints! Good luck to everyone for storms this week!

[East_England_Stormchaser91]

So my assumption is once storms become elevated, they will go in the direction of winds aloft too?

Indeed they will do, yes. Best thing to look at for tracking storms are the winds at 500hpa or 300hpa. Not sure which one is optimum, but either of those two will give a good indication on what way the storms will track. 

Caveat being that if a storm develops supercellular characteristics and becomes severe, it will likely deviate 10 degrees or more to the right of the mean 500hpa winds. 

Hope that helps

Edited August 12, 2015 by East_England_Stormchaser91

[lassie23]

This latest quote from Weatherweb TV  "Still much uncertainty surrounds the thundery rain on Thursday. Current ideas are that thundery outbreaks of rain reach southern England early on Thursday morning before travelling erratically northwards during the morning, to be through Wales, the Midlands and East Anglia by the end of the morning and into the early afternoon. It's then the turn of northern England to experience the threat of thundery rain through Thursday afternoon, eventually arriving into Scotland in the evening. This progression is by no means certain and much could change."

 

It's in uncertain times like these, that one turns to Metcheck for guidance.  

[Rain123]

How do you find the winds at 500hpa?

[tomp456]

They are firing up down south, but i'll hold off, since The English Channel is a classic storm killer.

The thunder may get sucked out, and we end up with outbreaks of thundery rain instead

Everyone knows that is exactly what's going to happen. 

[Andy Bown]

It's quite rare to have a set up where storms are present already over Northern France rather than waiting for them to explode from the South Coast (as with 3rd July this year and July/Sept last year). But than in itself means we should probably expect further rapid development once the storm front/trough reaches the South Coast in the early hours tomorrow, so it won't matter if the current storms decay somewhat  although with them being elevated I don't expect them to.

 

In a way it's unfortunate that the timing means it will be daylight when things kick off because that makes lightning viewing harder and the storms have to be nearer your location, unlike the 3rd July where lightning was visible from miles and miles away.

 

Forecasts are now kind of irrelevant, it's a total nowcast and radar watch event from here on since we know the forecast rain/storm positions are extremely unlikely to be accurate.

 

I await the wailing and gnashing of teeth from those whose own back yards are not affected ; please remember the best (worst?) storms will only affect a relatively small percentage of the country.

[Cableguy]

They are firing up down south, but i'll hold off, since The English Channel is a classic storm killer.

The thunder may get sucked out, and we end up with outbreaks of thundery rain instead

Isn't that what's forecast anyway though? Edited August 12, 2015 by Cableguy

[Tom dewey likes thunder]

I think thoes stroms over fance wont die uk over here uk be it is humid and mugg out

[LeeKay]

A small development on going nr Gloucester, see radar & Sat 24 bearing North...