Storms and Convective discussion - 10th April 2020 onwards

[Allseasons-Si]

15 minutes ago, Zak M said:

Here we go - updated version of Windy (they have many models on display in the bottom right but I am using the ecm)

   

   

The ECM is pinpointing East Anglia as the best place to see storms on Thursday.

I'd best put some fuel in.

[Paul Sherman]

Yh believe it when I see it - But if it holds together will be chasing that for sure

[Zak M]

Hmmm... has anyone seen the GFS 18z? (Or the GooFuS as @Paul Sherman likes to call it ) It has thunderstorms developing in the morning at 9am on Thursday... bit strange as that's the first model to show the thunderstorms developing that early but the GFS has its swings so it probably won't show it the next run 

Edited May 17, 2020 by Zak M

[Zak M]

Storm risk map is an eye-opener:

   

[Allseasons-Si]

1 minute ago, Zak M said:

Storm risk map is an eye-opener:

   

I'd best put a full tank in

[ChannelThunder]

19 minutes ago, Zak M said:

Storm risk map is an eye-opener:

   

Wow, GFS definitely upping the game now. Not sure on that timing though, it's got them first developing at 6am, so it must be seeing some elevated potential. If it could bring it forward by 6 hours so I can get some night time photos, I'd be delighted! 

[staplehurst]

19 minutes ago, Zak M said:

Hmmm... has anyone seen the GFS 18z? (Or the GooFuS as @Paul Sherman likes to call it ) It has thunderstorms developing in the morning at 9am on Thursday... bit strange as that's the first model to show the thunderstorms developing that early but the GFS has its swings so it probably won't show it the next run 

General consensus amongst model guidance is for two main areas of interest - potential for elevated showers/thunderstorms in the morning hours, not necessarily imported from France but perhaps more developing 'overhead' as the approaching upper trough engages with the warm plume over E / SE Britain. Assuming morning convection clears smartly then there would be potential for surface-based thunderstorms to develop in the afternoon / early evening across eastern England.

However, all of this is hugely dependent on the exact shape of the upper trough, and this varies from model to model, and even run to run of each model, hence the uncertainty. If the upper trough is less developed/sharp, then less engagement with the plume will occur and consequently the chances of anything developing will be less. We also need to consider timing issues - if the trough swings through too quickly, then it won't coincide with peak diurnal heating for example. Then of course, if elevated convection does develop in the morning hours, this notoriously produces a lot of cloud that tends to inhibit surface-based development in the afternoon. 

So lots to play for, and in forecasting terms a long way away. I've been keeping my eye on Thursday for a while now, but probably won't get too excited until at least Tuesday. there is potentially some reasonable shear at play, so any storms that do develop on Thursday afternoon could become fairly well-organised for a time - but again this depends on how the upper pattern evolves, and we'll have to wait a few more days to be able to iron out that detail...

[matt111]

40 minutes ago, Zak M said:

Storm risk map is an eye-opener:

   

Suddenly I'm interested 

[Flash bang flash bang etc]

2 hours ago, lancem said:

Wow, GFS definitely upping the game now. Not sure on that timing though, it's got them first developing at 6am, so it must be seeing some elevated potential. If it could bring it forward by 6 hours so I can get some night time photos, I'd be delighted! 

I was wondering about elevated potential, if I was to choose I would definately go for the early hours‘ storms as a preference cos I’m not driving to Kings Lynn again

[Thunder and Lightning]

Well the NetWx MR is definitely liking CAPE...

[Flash bang flash bang etc]

Just now, Thunder and Lightning said:

Well the NetWx MR is definitely liking CAPE...

Wow  

[Eagle Eye]

intersting netweather forecast 25% yet i'm in the mddle of the 60-70%

[Thunder and Lightning]

Don't always take % forecasts literally, also what forecast and what 60-70%?

 

[Eagle Eye]

thunderstorm risk map

[Eagle Eye]

thinking about it probably thinks i meant the woodchurch in liverpool

[ChannelThunder]

Yeah, really don't take percentages literally at all, especially 3 days out. Also, GFS is a low-res model.

[Eagle Eye]

On 13/05/2020 at 15:36, Xanderp009 said:

signs of rotation even if it is over 7 days away.

 

hmm isn't it remnants of tropical storm arthur

[Thunder and Lightning]

The UKV is looking really good so hopefully it keeps up! The weird thing is it is developing most of the storms in the morning which I don't want as I will be in exams.

Edited May 18, 2020 by Thunder and Lightning

[Thunder and Lightning]

Just now, Thunder and Lightning said:

The UKV is looking really good so hopefully it keeps up! The weird thing is it is developing most of the storms in the morning which I don't want has I will be in exams.

Or early in the afternoon

[Eagle Eye]

oh dear, for some reason bbc is saying on friday, every other weather channel says thursday

[Zak M]

Thursday looking really interesting now, especially for East Anglia!

It's showing a max of 2,000j/kg CAPE!! 

Edited May 18, 2020 by Zak M

[Harry]

23 minutes ago, Xanderp009 said:

oh dear, for some reason bbc is saying on friday, every other weather channel says thursday

BBC obviously thinking that the clearance of the instability will take longer - Darren Bett funnily enough mentioned this last week, that models have a tendancy to shunt Highs eastward more quickly and therefore speed up breakdowns. It wouldn’t surprise me therefore if they are favouring a slower breakdown and hence the emphasis more for Friday. I personally will take a slower breakdown as I have Friday off

[ChannelThunder]

21 minutes ago, Harry said:

BBC obviously thinking that the clearance of the instability will take longer - Darren Bett funnily enough mentioned this last week, that models have a tendancy to shunt Highs eastward more quickly and therefore speed up breakdowns. It wouldn’t surprise me therefore if they are favouring a slower breakdown and hence the emphasis more for Friday. I personally will take a slower breakdown as I have Friday off

Me too! Thursday morning is no good for anyone who has a 9-5 job! If this could all be delayed until Thursday night, that'd be ideal!

[Mapantz]

37 minutes ago, Zak M said:

Thursday looking really interesting now, especially for East Anglia!

It's showing a max of 2,000j/kg CAPE!! 

And for a comparison..

I suspect it's overcooking dewpoint temperatures, similar to what the GFS does.

[Ben Sainsbury]

Yeah agreeing with much of the chat regarding next Thursday, general consensus is for a few home-grown elevated storms to develop across CS England and the far South. The risk generally to transfer eastwards with the potential for storms to root to the boundary layer to become surface based or for other surface based storms to form late morning across SE England and East Anglia. NMM generally tends to over-blow CAPE values but even then we are still looking at 1000J/Kg respectively. Decent DLS too as mentioned so chance of organisation and/or weak home-grown MCS as hinted by NMM. Steep lapse rates too so some quite frequent lightning at times. Though all subject to changes over the coming days.