Stormy Wednesday 15th August 2012

[Coast]

Well I'm working both nights on the Hoe so we'll have to see.

I understand in modern 'gangsta' parlance, that would have a totally different and rude meaning!!!!!

[Harry]

I understand in modern 'ganagsta' parlance, that would have a totally different and rude meaning!!!!!

As opposed to gangsta parlance

[Coast]

As opposed to gangsta parlance

"Sorry ladies and gentlemen, this thread will be re-railled at the next convenient point....."

Back to the storm! I'm liking the SkewT for Herkymoo tomorrow afternoon:

Thunderstorm indicators:

http://www.skystef.b...orm-indices.htm

[AWD]

Met Monkey providing an interesting forecast for tomorrow too.

http://null.co.uk/

[Biggin]

"Sorry ladies and gentlemen, this thread will be re-railled at the next convenient point....."

Back to the storm! I'm liking the SkewT for Herkymoo tomorrow afternoon:

Thunderstorm indicators:

http://www.skystef.b...orm-indices.htm

Im sorry I still dont have a scooby what that graph is showing Coast

[Coast]

Im sorry I still dont have a scooby what that graph is showing Coast

(I don't really either!!! ) The best way is to start here:

http://forum.netweather.tv/topic/16002-a-simple-guide-to-understanding-skew-t-diagrams/

or here:

http://www.downunderchase.com/storminfo/stormguide/PDF/Storms07.pdf

There is a great convective chart guide here:

http://lightningwizard.com/maps/ConvectiveWeatherMaps.pdf

and this is the easier way for now, to take the numbers at the top of the SkewT and get some feel for what they mean and might bring: http://www.skystef.be/storm-indices.htm

SatRep have the progression of the front into tonight as:

[bpcpal]

The metoffice rainfall map now have the rain coming through alot earlier also.

[Chris K]

The metoffice rainfall map now have the rain coming through alot earlier also.

Yea I noticed this. Going by their forecast, the rain will have cleared the SW and most of Wales by time it gets to 1500hrs. The SE still seeing some showery rain and the main band being across N Ireland, Northern & Central England.

[Coast]

The metoffice rainfall map now have the rain coming through alot earlier also.

United Kingdom

Rain

Issued at: 1145 on Tue 14 Aug 2012

Valid from: 0600 on Wed 15 Aug 2012

Valid to: 2359 on Wed 15 Aug 2012

Heavy rain, accompanied by strong winds, is expected to spread north during Wednesday morning and afternoon, to affect parts of western England, much of Wales and Northern Ireland. The heaviest rain is likely to clear from the south by evening, but the strong winds will peak a little later.

The public should be aware of the possibility of surface water flooding and the likelihood of difficult conditions for travel and some summer holiday pursuits.

http://www.metoffice.gov.uk/public/weather/warnings/?regionName=uk

[Gavin P]

Here's my latest video with a detailed look at stormy Wednesday;

http://gavsweathervids.com/

Worst of the weather seems to be in central and western parts?

[Luke]

Does anyone else think the Met Office warnings need to be extended?

[Costa Del Fal]

I really just think tomorrow will be frontal rain now. I would expect the Meto to pick up on this by now if there was potential. Some heavy rain yes but that looks it I think. Not completely ruling thundery weather out just yet though.

[Cheshire Freeze]

I really just think tomorrow will be frontal rain now. I would expect the Meto to pick up on this by now if there was potential. Some heavy rain yes but that looks it I think. Not completely ruling thundery weather out just yet though.

I'm feeling the same. Looks like a bust rather than a 'boom' situation to me.

[Chris K]

I really just think tomorrow will be frontal rain now. I would expect the Meto to pick up on this by now if there was potential. Some heavy rain yes but that looks it I think. Not completely ruling thundery weather out just yet though.

Yea, purely based on gut feeling, this is what I think. Perhaps some random sferics appearing on radar here and there where conditions are favourable, but I can't see anything substantial happenning.

Well, apart from the fact it'll be wet, wet, WET at some point during the day for much of the country and possible flooding in some areas, where the heaviest rain falls.

Edited August 14, 2012 by Chris K

[Costa Del Fal]

I mean dont get me wrong there are some fantastic ingredients there but there just looks like going to be no trigger, too much cloud, wrong time, short space of time for firing etc.

[knocker]

Meteoalarm only appear to hve yellow warnings out for Leinster and Munster.

http://www.meteoalarm.eu/en_UK/0/0/IE004-Leinster.html

[Mapantz]

Still looking good from where i'm standing. Certainly some hotspot action in the Midlands and running through to the usual places like Lincs etc .. tornado formation possible given wind shear amounts. Don't start bailing out just yet.

[TheToastPeople]

TORRO used the MCS word for tomorow.... http://www.torro.org...te/forecast.php

TORRO CONVECTIVE OUTLOOK issued on Tuesday August 14th at 12:50GMT

A rapidly deepening depression will approach south-western parts of the British Isles overnight, and will push a plume of moisture and reasonably steep lapse rates across many places on Wednesday. Wind shear will be sufficient for organised convection, especially across England and Wales. However, the evolution of the activity is unclear at the moment. If precipitation is widespread along the cold front (which seems quite likely given the strong ascent) then embedded thunderstorms, perhaps an MCS, with strong winds and heavy rain, seems likely. If there is a lot of frontal activity it may be than overall convection is rather limited.

However, if the activity is somewhat more broken then well organised multicells and supercells may develop, mainly across England, on Wednesday. A risk for severe winds and perhaps a tornado would exist, along with reasonably large hail.

Conditions will be monitored and a discussion or watch may be issued in due course.

Forecaster: RPK.

Edited August 14, 2012 by Daveweiser

[Andy Bown]

Ian Fergusson on BBC Points West spoke of the heavy rain moving North with thundery element possible in the East of the region (Wiltshire/Dorset)

so what that means for parts further East I'm not sure.

What has surprised me is how there seems likely to be (in this region) a very wet period between around 07.00-13.00 and then almost a complete

clearance to a sunny afternoon/evening.

[legritter]

just had a look at sat 24 and our system is surely moving towards us ,stand by your beds gang and let the battle commence .potential there for embeddied storms and plenty of available energy but remember it is a very complex system and timing is critical ,location will be as usual some winners some losers , its good to hear that IAN FURGUSSON as mentioned thundery element in wilt/ dorset areas that puts us in with a good chance as for a professional to say it means they must be pretty confident . as always bear in mind whats heaven for us posters is hell for those flooded out ,the rest of week looks like being very active with again hot spots for storms and slow moving fronts ,cheers legritter

[Nick F]

All the ingredients are still there for severe storms to develop tomorrow across parts of England (Midlands, CS and SE England, E Anglia most likely) in the warm sector - DL shear in the order of 30-50 knts, 50-70 knt 500mb jet and dry air slot over-running a very warm moist plume (WBPTs and dew points of 18C) and strong deep and low-level shear. The concern is that cloudiness generated from the fronts may limit instability, though strong forcing may overcome the hurdle of cloudiness.

Quick look at parameters:

WBPT (Theta-w) plume of 18C advecting NW ahead of cold front swinging in from the SW:

Lightning Wizard charts derived from Hirlam suggest backed winds towards the surface and strong winds aloft will generate fairly strong Storm relative helicity, DL and LL shear overlaping the greatest potential instability in warm sector, supercell and significant tornado parameter areas highlighted from Midlands down to SE England/E Anglia at 15z:

Potential for large hail, damaging winds and tornadoes could further be helped by low LCLs and 500mb dry slot moving from the SW:

Will do a storm forecast for tomorrow later.

[matty40s]

I am taking a chance and leaving my boat on the River Soar (on loose ropes) , I would normally head off to a canalised section but have seen my present mooring over the last three months floods and think I am pretty safe to stay.

I do think there could be some exceptional weather tommorow, it is still 22C now, and there is not a breath of wind, once this low starts to stream in, it is going to suck lots of this moist warm air in and develop some interesting localised events.

[Weather Wizard]

This is from the US airforce (from my simplistic reading of it, it looks better than the FAX)

[Sunny Android]

Does anyone else think the Met Office warnings need to be extended?

The Metoffice have their eyes on the Maritime conditions

.... severe gales expected in East Central Section, Sole and Shannon.

With the low at 972mb on the +24hr Fax issued at 16:09UTC it could prove nasty.

I believe the Fastnet low in Aug 1979 was 979mb from a quick search on the internet !

Edit: the 982mB posted above isn't far different either ?

Edited August 14, 2012 by Sunny Android

[smoggyjester]

being a non technical person on here, but trying to learn, can anyone offer an opinion what weather we COULD experience in hampshire, south coast area tomorrow? thanks in advance