Convective / Storm Risk Discussion - 14th June 2013 onwards

[Boro Snow]

Some sferics towards coast from that heavy band over you Boro Snow.

not seen anything or heard any thunder paul just very heavy rain

[ZONE 51]

Do I get a film for the SLR for next week... bulb they call it.. open shutter for a minute or two and you might get one of those photos of lightning at night... this may shock the camera as it's not seen that before.. 

Edited June 16, 2013 by ElectricSnowStorm

[ZONE 51]

Data GFS 00z.

The image below is for this evening, this shows the hot and humid moist plume over Spain moving through France and towards the UK, Thickness 850/1000hpa:

Surface temps hot over Spain and France today:

 

This is the hot air-mass heading our way arriving as warm potentially very warm air across the south more especially the SE on Monday, the hotter air not to far away by Tuesday with a very humid air for some across the south.

I wouldn't be showing this in a convective thread if there wasn't the risk of thunder, so let's take a look at that risk. Just before that though I want to show you the Thickness 850/1000hpa for Tuesday:

 

Here it shows the warm and humid air has arrived, the deeper oranges across the southeast indicating very warm air here.

Next is the lifted index over the next 3 days, the yellow is unstable air, the oranges and reds indicate very unstable air-higher risk of thunderstorms more energy available in the atmosphere to use to create them:

Sunday evening(today)

Not much showing inland.

The unstable air comes with the plume of moist warm air, depending on how the Atlantic low pressure moves and where-this pulling up this air-mass:

This chart shows that area of low pressure to our southwest this evening.

Next more lifted index charts.

Monday morning:

Unstable air over France getting near to our shores

Monday afternoon(next)

This is thundery air, arriving through Monday, especially Monday evening and night

Monday evening/night:

Thunderstorms over France moving towards south UK, these most likely for the southeast

Tuesday 0000hrs next:

 

 

Precipitation Monday morning into afternoon:

 

 

Wet into SW UK.

 

 

 

Taking a look at Monday evening potentially thundery rain into the south/se, clusters of thunderstorms perhaps an large scale storm..could there be an MCS? won't answer that now..

 

 

Next is into Monday night/early hours of Tuesday:

 

I'm going to leave it there now look forward to posts from other's on this potential.

 

ESS

Edited June 16, 2013 by ElectricSnowStorm

[Supacell]

After a quieter day today there is another opportunity late tomorrow for some as per charts and explanation by ESS.

 

As is always the case with air-masses moving up from France a lot of caution is needed, for example will any storm activity that builds over France survive the Channel crossing? If the GFS is correct then eventually (probably more Tuesday/Wednesday) we import enough of this warm, humid and thundery air to develop our own home grown storms. IF being the operative word though, met office forecasts still only showing temperatures around the low 20's (not the high 20's being shown on GFS) although 21-23c is still plenty high enough for storms to develop if conditions are right. Furthermore, the met office tend to only use the "t" word around 24-48 hours before, so for now the fact they mention "heavy showers" will suffice

 

Monday evening and night does currently look like the south coast could see some thundery activity imported over the channel, but could just as easily be that the showers and storms stay just offshore giving those on the south coast a distant light show. A better idea later on today I think.

 

NAVGEM model shows temps of 32c in the SE on Wednesday.

 

 

Edited June 16, 2013 by Supacell

[ZONE 51]

Thanks SC. Just a thought, I think it is possible that some active electrical storms could not so up on the usual ppn charts even show nothing(until the near hrs where they are shown as small patches or intense cells if heavy). sometimes not much ppn reaching the ground.

Edited June 16, 2013 by ElectricSnowStorm

[Supacell]

Thanks SC. Just a thought, I think it is possible that some active electrical storms could not so up on the usual ppn charts even show nothing(until the near hrs where they are shown as small patches of intense cells), not much surface ppn from some stms.

 

Certainly next week looks interesting with a number of possibilities. Monday evening/night is the first opportunity of many

[Coast]

Certainly next week looks interesting with a number of possibilities. Monday evening/night is the first opportunity of many

 

I'm looking to Wednesday and Thursday for the main events on current potential:

 

 

 

 

Just a little bit to the North please!

 

 

BOOM!!!!!

 

[AWD]

CAPE looks good;

Skew T looks alright;

In simple terms, the 96 hour chart is the best I could get:

Unknown trigger?

Be an interesting and emotional few days me thinks!

[Coast]

Be an interesting and emotional few days me thinks!

 

Well it's difficult to be level headed when convective weather is a possibility and then are hopes are dashed, but we better try! :lol: 

[Ben Sainsbury]

What is up with the Charts!

[Coast]

What is up with the Charts!

Rmgfs876.gif ukcapeli.png

 

Well nothing from what I can see. Would be nice for a bit more of a Southerly element to those particular one (yes, in my back yard!!) but encouraging at this point.

[Cloud 10]

Yes,musn't start ramping for gfs potential 4 days away...

 

dewpoints..  temps...

 

 

precipitation..      ???...

 

 

[Ben Sainsbury]

Well nothing from what I can see. Would be nice for a bit more of a Southerly element to those particular one (yes, in my back yard!!) but encouraging at this point.

Can't get too excited;), but we'll have to see whether it develops or not.

[VillagePlank]

Wednesday looks very promising,

 

 

Primarily, this lot is caused by a warm moist plume advecting NNW'wards from Europe. You can see the extent of the heat and moisture,

 

 

But it's better (read: easier) to see the combination of heat and moisture using the Thete-E 850hPa chart,

 

 

Still, a few days, and this relys on macroscale synoptics to get it to reach our shores. Plenty of time for GooFuS to shunt it east .....

 

[AWD]

Remember guys, there is a lot more to this than just CAPE values.

For example, the GFS shows the best CAPE around the 84 hour mark, yet it doesn't show widespread thunderstorm potential until the 96 hour mark. Awaiting trigger???

[VillagePlank]

Remember guys, there is a lot more to this than just CAPE values.For example, the GFS shows the best CAPE around the 84 hour mark, yet it doesn't show widespread thunderstorm potential until the 96 hour mark. Awaiting trigger???

 

Surface heating is likely to be the trigger ...

[AWD]

Surface heating is likely to be the trigger ...

And that relies on the sun!

[VillagePlank]

And that relies on the sun!

 

Looks promising, at least for Heathrow area,

 

 

With that I wouldn't be surprised to see one or two local 28C pop up, especially with virtually no wind about, too.

Edited June 16, 2013 by Sparkicle

[Evening thunder]

Looks like a convergence line should provide a decent trigger should the GFS 00z happen exactly as progged:

 

This coincides with the best CAPE 

 

and sudden outbreak of precip (likely thunderstorms) at around this time:

 

 

Of course the details of this are very unlikely to verify exactly as shown right now, with considerable changes likely, but we'll see and could well get something interesting happening somewhere.

[AWD]

Looks promising, at least for Heathrow area,

850gefs.gif

With that I wouldn't be surprised to see one or two local 28C pop up.

I agree, temperature wise we look to see some very warm temperatures in the SE. How much sun and how much cloudcover there will be could be instrumental in determining the type and time of any convective activity though;

would prefer less cloud and more sun really, but this detail could chop and change. Whether we get homegrown storms Tues/Weds or we have to wait for the breakdown on Thursday is the question!

[VillagePlank]

GooFuS cloud cover forecasts tends to be very unreliable, I've always found, primarily because clouds are parameterised (ie high clouds will always be present in the model when RH > 70%, for instance?) I think we have to wait until it's into skew-t range. For now, an unstable warm moist atmosphere is forecast - and that's pretty good in and of itself!

 

EDIT: just checked my working; cloud condensate are now part of GooFuS as an independent variable.

 

Edited June 16, 2013 by Sparkicle

[Coast]

Potential solar radiation at the surface , midday Wednesday:

 

Surface temperature:

 

[VillagePlank]

Anyway, enough of this friendly banter. Time for some thunderstorm porn,

 

 

I'll eat my shorts if that comes off!

 

Edited June 16, 2013 by Sparkicle

[Coast]

I'll eat my shorts if that comes off!

 

 

Would you like ketchup with those Sir?

 

[IanR]

 More chance platting dry sawdust than a thunderstorm happening here this week