Convective Discussion

[Jane Louise]

Looks like some of you in the South and South East may get a storm tommorow according to this :(lucky lot if you do )

Thunderstorms

Very warm in south east

Monday

For Wales expect a good deal of cloud and a few showers in the morning then sunnier with isolated light showers for the afternoon. Mostly cloudy across central and eastern parts of England along with southern England. Here expect some showery rain that may turn heavy and thundery for the afternoon. For Scotland and Northern Ireland it will be sunnier with just a few scattered showers developing. We are looking at highs of 15 to 20C but up to 25C in the south east.

Monday Night

Any showers across eastern England are expected to fade away with much of Britain ending the day with some early evening sunshine though a few showers will affect western coasts. That's how it stays into the night with a few showers around western coasts of Wales, England and Scotland while the bulk of the United Kingdom is dry with clear spells. Lows at 9 to 14C.

http://www.weatheronline.co.uk/cgi-app/reports?LANG=en&MENU=202&DAY=20090823

[Costa Del Fal]

Lol another close miss for us.

[Coast]

Well well well! A level 1 for the SE tomorrow from Estofex:

Ruddy Hell!!! B) Haven't seen that for a while - I hope they're spot on!

What are the others saying?

TORRO have Friday's forecast still up, but that should change mid morning.

A big chart from the UKASF:

Storm Forecast Issued: 2009-08-23 23:20:00

Valid: 2009-08-24 00:00:00 - 2009-08-24 23:59:00

Regions Affected

England (excluding Cumbria and far SW), east Wales, W/SW Scotland, Northern Ireland, NW Ireland ( the whole of the United Kingdom is included in the WATCH )

Synopsis

A complex area of LOW pressure to the northwest of the United Kingdom, and HIGH pressure over the European continent to the east of the United Kingdom, will dominate the weather on Monday. Through the whole forecast period, a cold front will move eastwards across England, Wales and Scotland. To the east of this front, a warm and humid airmass is present thanks to light southerly winds advecting the airmass from France. Scattered showers and thunderstorms are expected to develop from mid-morning onwards, forming a trough ahead of the cold front, which will then move slowly eastwards. Current thinking is that any thunderstorms that do develop will be fairly isolated, but pose an enhanced large hail and/or tornado risk. There may be a few embedded thunderstorm cells along the cold front itself. Any thunderstorms that do develop will decay or move into the North Sea by 20z. During the late afternoon and evening hours, scattered showers and thunderstorms are expected to affect Northern Ireland, and western parts of Ireland and Scotland. Gusty winds and small hail may accompany these showers, which are expected to persist well into the night across coastal districts in particular

But don't get too excited as GFS has minimal lift, DP's and CAPE except for a small patch in EA:

London's overall view is slightly better later on:

Last nights Herstmonceux sounding dosen't hint at anything yet, the 12Z will be like waiting for the cricket scores today!!!!

and a few others, just for decoration and pretty colours......

I'd love to go with ESTOFEX today, but I'm super cautious and GFS looks like the other end of the scale. Should be interesting to see how it pans out, East Anglia late afternoon being the hot spot if anything breaks as my complete guess! B)

[Harry]

Same here - super cautious doesn't cut it! I don't think we will see anything here, though I would love to say otherwise (of course!!)

What gets me also, is the forecaster is the infamous, and MW's favourite, MR DAHL!! He is Mr Dahl who doesn't even give the UK yellow zones let alone Level 1's!! It states however that SHOULD anything develop it could be severe in nature - but of course we need the right things to come together.

Worth noting I saw train loads of ACas/Ac on my way into the office this morning, which is always a good to see.

Time will tell - and I am also V keen to see the Herstmonceux sounding - hazy blue skies here at the moment and warming up nicely, so who knows!?!?!

(EDIT - Deleted - sorry B))

[The PIT]

Just a polite request. When someone posts a huge amount of graphs and pics don't quote it as we're quite capable of reading it first time rather than having to scroll through a few screens a 2nd time.

I think today maybe interesting just got a feeling.

[maidstone weather]

What gets me also, is the forecaster is the infamous, and MW's favourite, MR DAHL!! He is Mr Dahl who doesn't even give the UK yellow zones let alone Level 1's!!

B) B) yeah i noticed that last night! Gave me a nice surprise

[Coast]

Encouraging signs to start the day - we have horizon to horizon of Altocumulus, a surface temp of 21.0 DgC already and the DP is rising from 15.9 DgC.

'stir over a low flame, add a pinch of instability and some moisture and leave for 12 hours.....' B)

[Harry]

Just heard seagulls flying around the office - felt like I was working in a coastal office, lol!!

Omen?? B)

[maidstone weather]

The skies here this morning are almost the same to last Thursday. Nothing happened here, but it went bang over some parts of East Anglia later in the morning B)

[Neilsouth]

Altocumulus coming up from the south here

I see lots of storms have fired across france

[azores92]

is there a problem on the radar? on the 8am met office loop, there looked like there was a lot of heavy rain situated across devon and parts of cornwall, which has now completely vanished on the 8.30 loop? B)

[maidstone weather]

Altocumulus coming up from the south here

I see lots of storms have fired across france

Neil you can't call them storms until they start produce thunder and lightning - of which none has been detected yet B)

Azores, looks like a temporary glitch, there's rain over the SW on all the other frames. B)

[Neilsouth]

Neil you can't call them storms until they start produce thunder and lightning - of which none has been detected yet B)

http://www.meteox.nl/h.aspx?r=&jaar=-3&soort=satradar

Funny that B)

[Harry]

Neil you can't call them storms until they start produce thunder and lightning - of which none has been detected yet B)

Azores, looks like a temporary glitch, there's rain over the SW on all the other frames.

I am quite surprised it is not electrical to be honest - some of that precip looks VERY intense!!

Sadly it doesn't look like reaching us either B)

EDIT - Oh, it is, lol

[Evening thunder]

is there a problem on the radar? on the 8am met office loop, there looked like there was a lot of heavy rain situated across devon and parts of cornwall, which has now completely vanished on the 8.30 loop? B)

Yes I think there must be. It was there at 8:20 on the Netweather radar, then at 8:25 it just vanished. But it didn't stop raining here!.. and now I cant tell if im going to be hit by another heavyish showery outbreak! Help! B)

[Coast]

I suppose movement and timing of the front will be important today and could be an indicator of when anything potentially kicks off: B)

[Neilsouth]

Tony Gilbert

UPDATE 8.30am Mon

Following on from Nigel & Dave's forecast.

Am rather skeptical about today's outcome, now!...Whilst this was only low level risk, it now seems to be just marginal.

Whilst potential instability at low mid levels remains a good cooling facility for any initial vertical development, several other suppressing factors are likely to continue to hinder today's outcome; Whilst mid level shear remains good, it is unlikely that cloud tops will now reach this level at any great speed and thus it is unlikely that the updraft will split from the downdraft efficiently. Troughing from the west continues to look weak and GFS now forecast less insolation potential. Freezing level looks to remain comparatively elevated reducing hail potential and limited or no surface convergence looks to hinder funnel potential.

Still probably worth checking the models after mid day. Hope things can turn more interesting by then

Those storms over france seem to be heading towards paris and not here , yet!

[Coast]

Those storms over France seem to be heading towards Paris and not here , yet!

Gather round this webcam and think Northerly thoughts!

www.paris-live.com

[Neilsouth]

Gather round this webcam and think Northerly thoughts!

http://www.meteox.nl/h.aspx?r=&jaar=-3&soort=satradar

[Harry]

Gather round this webcam and think Northerly thoughts!

www.paris-live.com

Looks like a bit of that Acas is ready to go

[Neilsouth]

Lots of altocumulus here , possibly indicating afternoon-evening activity.. Though going by luck lately just crap

[Harry]

Lots of altocumulus here , possibly indicating afternoon-evening activity.. Though going by luck lately just crap

Judging by the charts, and as ever Brickfielder's in depth analysis, the synopsis is thus:

Main areas of interest anywhere from say Humberside/Wash, down through EA, E Midlands and into the SE.

Chances of an isolated thunderstorm in any given area - 20-30%

Chances of a severe thunderstorm in the same area - 10-20%

To summarise - there is a small risk of a thunderstorm. However, should a thunderstorm develop it could be very pokey!!

Eyes peeled boys and girls, lol

[Neilsouth]

The altocumulus is really puffy looking , good good!

[Ross B]

I think that you are confusing the difference between an, out and out, isolated thunderstorm, with the thundery activity associated with the embedded convection that often occurs within frontal systems. either way, lightning occurs and the sound is thundery.

So, i take it, there was no thunder heard in Cheltenham ?

Na, i'm not confusing them. I guess the fact is the term is quite vague, lightning can occur i guess yes. But what i mean is, that lightning could occur once and at the totally opposite end of a frontal band but you can still get the thundery rain at the other end and the full band is described as thundery rain. Therefore you can still have thundery rain without hearing thunder, If you get me.

Anyway, enough of the thundery rain debate

I've started a new topic as this one is heading of course : http://www.netweather.tv/forum/topic/56509-storm-discussion/