Convective / Storm Chat And Discussion

[Cheshire Freeze]

NMM keen on a small area of thundery potential for the Midlands and perhaps Wales tomorrow with very decent Deep Layer Shear too. GFS also shows some instability. Been quite quiet around here recently so any interest would be good however i feel tomorrow will not produce anything more than a band of rain.

Just seen that, it's certainly interesting as up until yesterday the models were forecasting tomorrows rain to be convective in nature. Then, yesterday evening, this was removed and instead showed as patchy rain. As it stands some convective potential is being brought back.

[I remember Atlantic 252]

Sorry only moved over to this forum yesterday from null, still trying to navigate my way around

also could you put location in profile? Staffordshire big county, thanks, especially crucial in winter as can be big elevation differences

[Staffordshire]

Yeah just seen the models, don't really think we will get anything majour maybe a few cracks of thunder, looks alot more promising for Wednesday though.

[Thundery wintry showers]

I'll certainly be keeping an eye on Wednesday as it's my 27th birthday- I'll be up in Cleadon in Tyne and Wear for the day itself so maybe a bit too far north for the main zone but you never know!

My main concern is that sometimes, like today, frontal remnants hang around in this setup, bring extensive cloud cover and suppress convection due to lack of solar heating, so it's still "up in the air" IMHO.

[Nick F]

I'll certainly be keeping an eye on Wednesday as it's my 27th birthday- I'll be up in Cleadon in Tyne and Wear for the day itself so maybe a bit too far north for the main zone but you never know!

A little too far off for forecasting where storms are most likely on Weds but atm it looks like S and E Scotland, NE and E England look most favoured ... so fingers crossed for your B'day storm.

Looks like there's been a few storms along Northumberland coast this afternoon and eastern Scotland too:

Red dots and orange crosses today's sferics, blue yesterday's.

Had a few passing light showers here today, but the steeper lapse rates and forcing for storms looks to be across the NE today.

[A.J]

Hmm.....tomorrow is starting to peak my interest now...The GFS18z is continuing the theme of some convective rainfall in the Midlands tomorrow evening.....The chance of embedded storms looks a distinct possibility....the run shows some lower level instability and bouyancy...To add to that, Skywarn's GFS plotter shows some deep layer shear and a few hundred Joules of mid-level CAPE...interesting!

[Costa Del Fal]

Good run from the NMM 18z too. Some quite good storm ingredients there. Its just the idea of frontal rainfall that is causing me some slight doubts as we dont often see embedded storms like this but you never know. Good luck for tomorrow.

[Supacell]

I have to admit the Thompson index looks interesting this evening (courtesy of lightning wizard).

I cannot get access to any charts showing CAPE in the mid-levels but SB CAPE looks a bit meagre. Certainly could be something and with all that DL Shear there could be multicells should embedded thunderstorms occur.

Will it or won't it? I would be interested to get an experts opinion to either confirm or expel our thoughts.

[Staffordshire]

Certinally some good ingrediants there! This could bring me my 2nd storm of the year! I'll try asking Joey over at met

monkey, I'll go by his word !

[A.J]

I have to admit the Thompson index looks interesting this evening (courtesy of lightning wizard).

I cannot get access to any charts showing CAPE in the mid-levels but SB CAPE looks a bit meagre. Certainly could be something and with all that DL Shear there could be multicells should embedded thunderstorms occur.

Will it or won't it? I would be interested to get an experts opinion to either confirm or expel our thoughts.

Hi, I've found this site very useful to create custom charts... skywarn GFS plotter

So far this morning, theg GFS & NMM hi-res keep the idea of convective rainfall this evening for the midlands & parts of northen England, but thunderstorms look somewhat less favourable to my eyes, and less pronounced shear and modest MLCAPE values....Still, the potential is there, so fingers crossed!....Like yourself, hopefully Nick or Brickfielder will post later on on the possibilities

[Coast]

ESTOFEX start the day off with a map showing potential into Southern Britain, but the big stuff yet again reserved for the other side of the Channel:

Storm Forecast

Valid: Mon 20 Jun 2011 06:00 to Tue 21 Jun 2011 06:00 UTC

Issued: Mon 20 Jun 2011 02:13

Forecaster: DAHL

A level one threat has been issued across NE France mainly for large hail, damaging winds, and tornadoes.

SYNOPSIS

Progressive upper pattern continues ... with an upper trough over eastern Europe and another one over the Atlantic, approaching W Europe. The latter feature is accompanied by a SFC low, which allows moist/warm air to return to central Europe. Quiescent synoptic conditions persist across the southern portions of Europe.

DISCUSSION

... NE France ...

A focus for potentially severe convection seems to exist over NE France where some 1000 J/KG CAPE and about 20 m/s DLS will exist. Some WAA should persist through the day, which should provide large-scale ascent to aid in convection initiation. However, storm coverage is uncertain and is not coherently simulated by the different models. Expect isolated thunderstorms, the most intense of which may produce large hail and damaging wind gusts. LLS will increase towards the NE, being maximized outside the region where instability exists. Still, storms over the NE parts of the LVL1 area may pose an additional threat for a brief tornado or two.

UKASF say:

Last Updated: 20:06 Sunday, 19th June 2011

Valid: 06:06 Monday, 20th June 2011 - 05:06 Tuesday, 21st June 201

Areas Affected: None.

Discussion:

An area of low pressure will move near Ireland from the Atlantic, this will push a series of fronts in from the southwest during the day. While some of the rain may be heavy in southwestern parts of Britain and Ireland, it is unlikely to be thundery through Monday morning. A little remaining unstable air could generate a few sharp showers in eastern Scotland during the afternoon, but these are not expected to be thunder

TORRO and SkyWarn have nothing. 21st OWS have it to the West of the UK:

UKMO charts showing Wales and the West as well:

NOAA's mid level significant weather chart say middle of the UK:

THE GFS KO index highlights the coast of France:

As does the soaring index (with something into Wales a little later):

CAPE seems to peak at midday but way over to the East and North:

You can just make out the boundary layer wind sheer over the French side of the Channel during the middle of the day here:

Low level lapse rates for the SE:

A lot of ingredients are there today, but none of them in the same place at the same time!!!! Very messy and anybody's guess - but I'm not holding out great hope.

[Harry]

Same here, Coast.

Estofex's chart indicates some outside hope, particularly if you're on the Kent coast, but with such a messy frontal picture, :cc_confused: springs to mind.

Even John Hammond said last night this is going to be very difficult to nail down and 'hopefully' they'll have a better idea as the forecast period progresses.

There's a tongue of moisture shown by GFS to extend into the frontal system this afternoon. This has prompted a level 1 for the NE France for the risk of some severe storms. How the CAPE will integrate with the waving fronts though is the $64,000 question. My guess is that there could be some intense pulses of rain within a frontal zone moving through this evening. The final position of the fronts though could be the difference between a few hours of drizzle, or something more interesting.

I think this is something for the likes of BrickFielder and NF to guide us on (if they would be so kind )

Edited June 20, 2011 by Harry

[A.J]

Aha! I can see the Sherminator lurking at the bottom of the page!....Nice to see back on the thread after your mammoth expedition stateside

Bet you're looking forward to our 'powder-puff' UK storms? :lol:

[Coast]

Bet you're looking forward to our 'powder-puff' UK storms? :lol:

Or none at all!! <_<

[A.J]

Or none at all!! <_<

Thats very true!......mind you, I think that May 9th monster I had has probably filled up my storm quota for the year!

[Nick F]

Does look like the potential for some embedded convection along the occluding front pushing northeast across England and Wales this evening/overnight - forcing perhaps aided by jet streak strengthening from SW across central/southern UK which may create upper divergence and enhanced lift for convection. Though can't see anything other than the odd isolated weak storm with rumble or two atm - more particularly for SW England, Wales, Midlands and Nern England this evening/early night.

[Harry]

I know it's against every rule going on this forum and the mods will slaughter me!

But there's a few occasions where pornography HAS to be allowed

http://www.wetterzentrale.de/topkarten/fsecmeur.html

(see 27-29 June)

Edited June 20, 2011 by Harry

[Costa Del Fal]

The 06z GFS has pretty much got rid of tonight's risk but given tonight's set up I'm not surprised one bit. Just a very outside chance of a rumble or two now.

[Harry]

The 06z GFS has pretty much got rid of tonight's risk but given tonight's set up I'm not surprised one bit. Just a very outside chance of a rumble or two now.

In my opinion, the 06z is a better set of charts than the 00z. Progs heavier precipitation, storm risk has dropped from a 50% risk to 40% in a few areas, but the risk area has expanded quite significantly across southern England.

[Dorsetbred]

Aha! I can see the Sherminator lurking at the bottom of the page!....Nice to see back on the thread after your mammoth expedition stateside

Bet you're looking forward to our 'powder-puff' UK storms? :lol:

Yeah but the thing is we are talking about real men being able to chase real storms. None of that US 30omile wide jobs, where you sit and wait and they come to you.

This is the UK, where chases are earned not given

Exits with his coat over his arm

[Stuart]

in FI about 180 hours the LI and caps look good for storms so I hope but it will get downgread

[Andy Bown]

Message for any of the East Somerset/Wiltshire members ...

... I went away for 36 hours over the weekend and after leaving my rain gauge empty at 10am on Saturday I found 17.5mm in it on my return

last night. Assuming yesterday was dry that means there must have ben some downpours between Saturday late morning - evening. Was there any

thundery activity? Thanks.

[Staffordshire]

Hey still any potential tonight I don have time to check the previous post as I'm going out in 5 but if you could leave a post letting me know for when I come back it would be much appreciated!

[Costa Del Fal]

Hey still any potential tonight I don have time to check the previous post as I'm going out in 5 but if you could leave a post letting me know for when I come back it would be much appreciated!

Im pretty confident in saying No to thundery activity.

[Staffordshire]

Im pretty confident in saying No to thundery activity.

Hey Im back an okay thanks what about Wednesday?