Storm & Convective Discussion - 01/03/15 onwards

[NO LONGER POSTING]

 

 

 

 

 

Backing up the post above small risk of a storm in the South east tomorrow... 

Edited May 21, 2015 by Surrey

[Flash bang flash bang etc]

All the frustration from the forecast models has brought out the poet in me:

Plume, plume come along,

Bring me lightning bright and strong,

Send me gust fronts, hail and rain,

From the warm air made in Spain.

Checking forecasts - fingers crossed!

No more chilly days or frost,

No more sparse anaemic lightning,

I want level 3's - they're frightening!

Checking radars - here they come!

Bay Of Biscay brewing some,

Impressive storms with epic cores,

Will they make it to our shores?

Supercells pushed up from France,

Making my emojis dance,

Rotating storms for us to chase,

And photos for my fireplace.

I'm running out of words that rhyme,

But hoping it is nearly time,

For all of us On this fair isle,

To get the plumes - and make us smile :-)

[Harry]

LOVE IT - you've now inspired me

 

Tuesday brought much needed thunder

But now I start to think and wonder

When a plume may come about

To give us all a chance to shout

 

But, there can be no denying

Plumes are awesome, awe inspiring

Hot and humid brings us the best

Perhaps a 2 from Estofex

 

Alas, for all so far this year

A decent plume has not come near

But when it does you can be sure

Awesome storms will come ashore.

 

An MCS brings joy for all

Forked and sheet but maybe ball

Torrential rains and maybe hail

With gusty winds, perhaps a gale

 

For now the charts may go nowhere

It's only May so dont despair

If July last year is now the norm

We will be in for awesome storms!!

 

Now to end this hopeful rhyme

A word of warning, its el nino time

I can't be any more specific

Beyond there's change afoot in the Pacific 

Edited May 21, 2015 by Harry

[Flash bang flash bang etc]

LOVE IT - you've now inspired me

 

Tuesday brought much needed thunder

But now I start to think and wonder

When a plume may come about

To give us all a chance to shout

 

But, there can be no denying

Plumes are awesome, awe inspiring

Hot and humid brings us the best

Perhaps a 2 from Estofex

 

Alas, for all so far this year

A decent plume has not come near

But when it does you can be sure

Awesome storms will come ashore.

 

An MCS brings joy for all

Forked and sheet but maybe ball

Torrential rains and maybe hail

With gusty winds, perhaps a gale

 

For now the charts may go nowhere

It's only May so dont despair

If July last year is now the norm

We will be in for awesome storms!!

 

Now to end this hopeful rhyme

A word of warning, its el nino time

I can't be any more specific

Beyond there's change afoot in the Pacific

Fantastic!

[Flash bang flash bang etc]

I cast a keen storm-chaser's glance,

On charts and radar, there's a chance

The giant storms - which likely will

Drift up past Urville-Nacqueville

Will reach us and bring forth the gift,

(With welcome CAPE, lapse-rates and lift)

The forks and balls and sheets and sprites,

Which entertain through summer nights!

Alas they fade - PAH! Foiled again!

And all we get is patchy rain.

I sulk, I sob, I sniff, I blub,

And put posts in the "No Storms Club"

My sweary posts are soon deleted,

I go to bed, all hopes depleted.

But then good news to make me cheer:

Another plume perhaps next year!

[Harry]

Nice CG cap there, Supa. Looks pretty close. 

 

Outlook wise in the medium term, as Harry says, looking crap to say the least with models showing no real signs of ridge building over mainland Europe, but instead troughs regularly dropping over UK or the east. 

 

Short term, still a marginal risk of heavy showers and an isolated storm or two late tomorrow afternoon across E/SE parts, where temps possibly to 20/21C and dew points in the low teens generates marginal CAPE build-up ahead of weakening cold front(s) moving south across the country. Conditions in general far from ideal - mid-level lapse rates not exactly high, weak shear, and forcing aloft absent. However, afternoon heating of decently moist airmass and light converging sfc winds may produce, as suggested by UKMet.  GFS the only model, though, that breaks out any precip.  

 

Agreed, GFS appears very keen to break something out across the SE tomorrow afternoon/evening - favoured spots appear to be Cambs/Suffolk/Essex and perhaps E Kent.  MetO pointing to risk of isolated heavy showers...in fact latest forecast suggests these are "likely to develop". The charts posted helpfully by Surrey point towards something more widespread geographically but still very isolated in nature.

 

I'm off tomorrow so would be awesome timing if there is something - best bet to check out the charts later this evening/tomorrow morning.

Edited May 21, 2015 by Harry

[NO LONGER POSTING]

Agreed, GFS appears very keen to break something out across the SE tomorrow afternoon/evening - favoured spots appear to be Cambs/Suffolk/Essex and perhaps E Kent.  MetO pointing to risk of isolated heavy showers...in fact latest forecast suggests these are "likely to develop". The charts posted helpfully by Surrey point towards something more widespread geographically but still very isolated in nature.

 

I'm off tomorrow so would be awesome timing if there is something - best bet to check out the charts later this evening/tomorrow morning.

Charts have improved somewhat this afternoon

[Mapantz]

Charts have improved somewhat this afternoon

 

If you're referring to the GFS? I would say the opposite. The 12Z is a downgrade from the 06Z - Not that there was much to downgrade from, of course.

Edited May 21, 2015 by Mapantz

[Greeny]

If you're referring to the GFS? I would say the opposite. The 12Z is a downgrade from the 06Z - Not that there was much to downgrade from, of course.

I haven't looked but I favour Surrey's comment cause its what I prefer to happen

[Tom Jarvis]

Estofex still not working??

[Harry]

Nope - estofex going down this time of year is not helpful.

Still some opportunity tomorrow evening in the SE - UKMO and GFS still pointing towards something heavy breaking out but I'm not sure about electrical activity...look forward to reading people's thoughts tomorrow

[timeless]

FYI, regarding Estofex it seems they are updating their servers OS, tho thats about all lve heard... seems they might be having issues getting everything just just right (information sourced from their Facebook page).

Edited May 22, 2015 by timeless

[NO LONGER POSTING]

Bit of a change re this afternoons slim jim chance for a hefty shower..

 

 

 

 

 

 

 

 

 

 

 

 

So nothing special what so ever, but chance of a few sharp shower perhaps very very lucky people if they do pop up may get a rumble.. 

 

Sun is out here but hazy need to burn back some more of this cloud!

[Harry]

This forecast is from Dan at Convective Weather UK:

Day 1 Convective Outlook

VALID 06:00 UTC Fri 22 May 2015 - 05:59 UTC Sat 23 May 2015

ISSUED 23:17 UTC Thu 21 May 2015

ISSUED BY: Dan

Some marginal instability on Friday afternoon/evening as a warm, moist surface airmass destabilises in response to diurnal heating and wind convergence. Scope for a few showers and isolated thunderstorms given instability at both surface and in the mid-levels. Shear is very weak, with only marginal CAPE, so likely to be fairly isolated and disorganised if anything does develop. Main threat, given high PWAT and slow shower/storm motion, would be from locally large rainfall totals.

On the 00z GFS charts a CZ persists for a number of hours in a line roughly from Great Yarmouth, through Ipswich, Southend and into the Medway area, perhaps extending as far south Sevenoaks/Tonbridge area. Conversely precipitation breaks out further west as discrete cells rather than CZ activity. Interesting.

Edited May 22, 2015 by Harry

[Noahjoe]

This forecast is from Dan at Convective Weather UK:

Day 1 Convective Outlook

VALID 06:00 UTC Fri 22 May 2015 - 05:59 UTC Sat 23 May 2015

ISSUED 23:17 UTC Thu 21 May 2015

ISSUED BY: Dan

Some marginal instability on Friday afternoon/evening as a warm, moist surface airmass destabilises in response to diurnal heating and wind convergence. Scope for a few showers and isolated thunderstorms given instability at both surface and in the mid-levels. Shear is very weak, with only marginal CAPE, so likely to be fairly isolated and disorganised if anything does develop. Main threat, given high PWAT and slow shower/storm motion, would be from locally large rainfall totals.

On the 00z GFS charts a CZ persists for a number of hours in a line roughly from Great Yarmouth, through Ipswich, Southend and into the Medway area, perhaps extending as far south Sevenoaks/Tonbridge area. Conversely precipitation breaks out further west as discrete cells rather than CZ activity. Interesting.

If you don't mind me asking, what is a CZ??

[Harry]

Not at all - it's a Convergence Zone, where winds blow towards each other and collide. If you look at the charts above posted by Surrey, you can see the lines colliding in the areas I mentioned above, roughly along the Norfolk, Suffolk, Essex coastlines. It is not a classic CZ as the wind flow is not hitting full in the face (ie winds from the west colliding with winds from the east) but it just might be enough the force the air upwards to form some showers.

There are other examples on those charts of CZs (see across the SW and NE of England), however the only realistic chance of any storms today is across the SE quarter.

Edited May 22, 2015 by Harry

[NO LONGER POSTING]

Not at all - it's a Convergence Zone, where winds blow towards each other and collide. If you look at the charts above posted by Surrey, you can see the lines colliding in the areas I mentioned above, roughly along the Norfolk, Suffolk, Essex coastlines. It is not a classic CZ as the wind flow is not hitting full in the face (ie winds from the west colliding with winds from the east) but it just might be enough the force the air upwards to form some showers.

There are other examples on those charts of CZs (see across the SW and NE of England), however the only realistic chance of any storms today is across the SE quarter.

 

[Noahjoe]

Not at all - it's a Convergence Zone, where winds blow towards each other and collide. If you look at the charts above posted by Surrey, you can see the lines colliding in the areas I mentioned above, roughly along the Norfolk, Suffolk, Essex coastlines. It is not a classic CZ as the wind flow is not hitting full in the face (ie winds from the west colliding with winds from the east) but it just might be enough the force the air upwards to form some showers.

There are other examples on those charts of CZs (see across the SW and NE of England), however the only realistic chance of any storms today is across the SE quarter.

Oh right, thank you! I had some knowledge of convergence zones just couldn't put two and two together :')

[Harry]

Had some good sunshine and heating here so far today...humidity feels ok too. Couple of ingredients therefore seem to be in place which is positive...now some lift!

[NO LONGER POSTING]

Had some good sunshine and heating here so far today...humidity feels ok too. Couple of ingredients therefore seem to be in place which is positive...now some lift!

Would agree, sun been in and out all day so far some clearer spots now on Sat, what I will say is that flow is so so slack anything that does pop up will be very slow moving

[Harry]

Aye, agreed. Little cumulus overhead moving along at a snail's pace. Feels like a downpour is in the offering but some forecasts on TV seem unconvinced.

Edited May 22, 2015 by Harry

[Greeny]

Nice and warm here in Norwich, Some convection is starting to show and cloud cover is increasing.

Edited May 22, 2015 by Greenday

[Paul]

Some cells popping up in the midlands now, about in line with the NetWx (NMM) model had them developing this pm, they should move slowly SE.

[Harry]

Clouded over here now, still warm but cooler breeze picking up.

[Eye to the sky]

Some cells popping up in the midlands now, about in line with the NetWx (NMM) model had them developing this pm, they should move slowly SE.

We had threatening skies here earlier with a few big spots of rain.This has all cleared now to leave a warm sunny afternoon.