Storm & Convective Discussion - 01/03/15 onwards

[Harry]

Whilst we've seen storms come out of not much, I'm not confident that laters set up has enough oomph to give anything more than maybe a couple of strikes for a very select few.

 

I am of course happy to be proved wrong!

 

Admittedly I'm of the same mind too, also hoping to be proven totally wrong

[Greeny]

Admittedly I'm of the same mind too, also hoping to be proven totally wrong

Speaking only as an amateur, it may depend on the position of the cold front intensifying during the night and catching the high theta-e present. judging by the wind charts the more west storms fire over in France the higher the chance that storms could clip south east and east. However at 850hpa winds take a sharp west turn if its early enough. The further east you go winds are heading towards the north sea and Benelux missing us completely. The storm risk chart indicates it as well.

[Mokidugway]

Speaking only as an amateur, it may depend on the position of the cold front intensifying during the night and catching the high theta-e present. judging by the wind charts the more west storms fire over in France the higher the chance that storms could clip south east and east. However at 850hpa winds take a sharp west turn if its early enough. The further east you go winds are heading towards the north sea and Benelux missing us completely. The storm risk chart indicates it as well.

as they normally do ...

[Daniel*]

Saying that Lauren we've had situations vice versa which failed spectacularly.

[Supacell]

Here is my take on the current charts and forecasts. BBC saying yes to some torrential downpours overnight and Euro4 shows something moving up from France behind the rain, but is this thundery? NMM earlier looked very good but has since shifted the activity to the far SE, although it does show some elevated CAPE across the south. GFS and WRF showing anything thundery will likely remain over the continent. Met Office show some interesting rainfall predictions moving into the south early on tomorrow but again, is this thundery.

 

In summary we have no real agreement with regards to any thundery activity which may import later in the night/tomorrow morning but we do have agreement on a lot of heavy rain along the complex of fronts tonight. I am assuming the thundery expectations are relating to what may happen after the rain band moves through and not within the rain band? Either way, the far SE of England appears best placed in the next 24 hours.

 

There are likely to be further thundery showers around the country through tomorrow, tomorrow night and Wednesday too but it is tonight which is generating the interest and rightfully so, plume thunderstorms are the best kind of storms in my opinion.

Edited May 4, 2015 by Supacell

[Lauren]

Saying that Lauren we've had situations vice versa which failed spectacularly.

Quite.

[Harry]

Here is my take on the current charts and forecasts. BBC saying yes to some torrential downpours overnight and Euro4 shows something moving up from France behind the rain, but is this thundery? NMM earlier looked very good but has since shifted the activity to the far SE, although it does show some elevated CAPE across the south. GFS and WRF showing anything thundery will likely remain over the continent. Met Office show some interesting rainfall predictions moving into the south early on tomorrow but again, is this thundery.

 

In summary we have no real agreement with regards to any thundery activity which may import later in the night/tomorrow morning but we do have agreement on a lot of heavy rain along the complex of fronts tonight. I am assuming the thundery expectations are relating to what may happen after the rain band moves through and not within the rain band? Either way, the far SE of England appears best placed in the next 24 hours.

 

There are likely to be further thundery showers around the country through tomorrow, tomorrow night and Wednesday too but it is tonight which is generating the interest and rightfully so, plume thunderstorms are the best kind of storms in my opinion.

 

Not at all, there seems to be some expectations that as the front starts organising, discreet embedded cells could fire anywhere along the warm front. This doesn't happen that often in the UK, but does in places like the US where warm front storms are not unusual by any stretch - in fact when I was out there 5 years ago (if I remember correctly) one of the best storms we witnessed was triggered by a warm front. 

 

Then in the unstable post frontal airmass, as the (if the FAX chart is anything to go by) army of cold/occluded fronts sweep through (around 6am ish) this could destabilise the warm/humid airmass behind the warm front, triggering something intense thundery downpours also. This to my mind seems the most likely chance to see any real thundery activity.

 

Just glanced at the UKMO and the rainfall intensity has dropped off along the warm front, however still keen on post frontal intense rainfall in the small hours (5-7am) across the SE. 

 

All a bit messy really...I don't like frontal stuff...too complicated lol!

 

For radar watching...Estofex in particular is quite clear that the atmosphere over BoB/W/N France is not set to detonate until evening/overnight 

Edited May 4, 2015 by Harry

[chapmanslade]

It does seem the two warm fronts are rushing N quicker than expected with quite a bit of dynamic rainfall on them about to hit the S coast soon.

 

It's the area to the N of Spain over Biscay where any action is going to start - the warm front looks pretty benign

[East_England_Stormchaser91]

Whilst we've seen storms come out of not much, I'm not confident that laters set up has enough oomph to give anything more than maybe a couple of strikes for a very select few.

 

I am of course happy to be proved wrong!

I remember one of best displays of lightning on 3rd July 99' I'm sure took place under similar Synoptics to this.

Looking back at various charts, witness feedback and satellite images to that spectacular night, the previous day saw modest temperatures of only 23-24c with a shallow low pushing up from France, with fronts pushing NE and the squeeze of very humid theta-e advection on the eastern edge. I'm sure this is what triggered the storms over the SE/ East Anglia that night.

This does not look to dissimilar as to what will happen tonight.

As has often been the case, some of the best events have happened at times when least expected, mainly with cloudy, humid and not excessively promising setups!

[NO LONGER POSTING]

Does feel like a good old storm is on the way though

[Lauren]

I hope so East!

[Harry]

Does feel like a good old storm is on the way though

 

I wish I had your optimism Surrey...while the skies have a kind of plume haze about them, if I hadn't been watching forecasts for several days I wouldn't be remotely inclined to think there was a thunder risk. That said, the conditions which may bring some thundery weather are some few hundred miles south of us currently, so I suppose it wouldn't feel remotely thundery anyway 

Edited May 4, 2015 by Harry

[Mokidugway]

Humidity has gone up starting to feel muggy out ,

[Lauren]

Feels like it's got colder here. Clouded over completely.

[Mokidugway]

Does have that feeling of it's going to go bang about it !!....

[Ǝssex Ǝasterly]

My guess is that the north sea will see most of the action

[Lauren]

Does have that feeling of it's going to go bang about it !!....

 

See, I don't think it feels that way at all.

[Flash bang flash bang etc]

If I was in France or Spain right now I'd get myself on the next train to Lincs... ;-)

[Mokidugway]

See, I don't think it feels that way at all.

and yet you're more likley to get somthing in you locale ..

[Sprites]

I remember one of best displays of lightning on 3rd July 99' I'm sure

Looking back at various charts, witness feedback and satellite images to that spectacular night, the previous day saw modest temperatures of only 23-24c with a shallow low pushing up from France, with fronts pushing NE and the squeeze of very humid theta-e advection on the eastern edge.

The temp. was 29c in London the day before.

I don't think we are actually in the "plume" this time...

Edited May 4, 2015 by Sprites

[Mokidugway]

Steric picked up on sat 24 ..

[Lauren]

and yet you're more likley to get somthing in you locale ..

 

Weather's a strange beast, innit?

[Atmogenic]

Well I just took my washing in and it has that muggy smell in the area where I live and iirc that was when a good storm came over me at night, it was a fantastic.

[A.J]

Steric picked up on sat 24 ..

if it's the one over the west country Moki, then I'm pretty sure it's a false detection....it showed up on the NWv6 radar then quickly disappeared off the radar archive, the atmosphere across southern england is relatively stable at the moment

[A.J]

first post frontal storms now firing over northern Spain....this is the expected area for development this evening (for interest to those in SE england)