Convective Weather Discussion Uk

[we1330]

Something seems to be brewing in the SW Midlands.

It does?

[weatherobsuk]

Got my eye on the Cardiff cell at the moment. In all likelyhood it'll dissipate with having to travel the 143 miles to get here, still its something rather than nothing keeping my hopes up, moreso if it induces convective forcing ahead of the cell as it approaches ever nearer into the Midlands which shall be in another hour's or so time.

[Kookylou]

well that was a nice bit of rain. but that was all - just rain!

[Thundery wintry showers]

Convection seems to be going up in Tyneside- some Ac Cas looming out of the haze in Cleadon, though it's hard to tell with patches of sea fog keep obscuring the view.

[Supacell]

Still crystal clear skies here. If there are to be any storms then i would expect they'll kick off properly within the next couple of hours. I've got my car and camcorder ready but in all honesty i'm not expecting to be using it, although wasn't expecting anything here anyway. Can't chase tomorrow so will have to wait patiently for the next chance whenever that is.

[essex coast matt]

showers and storms now popping up in belgium

[Wivenswold]

showers and storms now popping up in belgium

They are about 215 miles away at the moment and grinding slowly this way. I'm not hopeful of anything but a light show across the sea this evening.

[Stuart]

weather Under Ground show thunder storms here for sat let see if that Right

[Wet'n'Dry]

Thunderstorms wouldn't even travel a few miles under the current conditions -- it would more than likely dissipate within mere minutes of reaching maturity; the conditions are simply not conducive to increase thunderstorm longevity.

Whilst I'm still a relative newbie and probably don't know what I'm talking about, wouldn't a storm create it's own localised conditions and perpetuate updraught once an airflow has been established?

[weatherobsuk]

The problem today is there's so little moisture in the mid-layers any inflow would be dry-air entrailment as weather09 pointed out. The boost the Cardiff cell got probobally came from crossing the Bristol Channel and I may have gotten a little ahead of myself, but there still seems to be convection ahead of it from the convective forcing its producing so its that (rather than the actual shower itself) i'm keeping a eye on at the moment.

[knocker]

Seem to have lost a post somewhere. Anyway to repeat the METO forecast for Cornwall today hasn't covered itself with glory. Apart from the persrstant Ac this morning in the last couple of hours the cloud and rain???? seen on the radar and sat. has arrived. It is quite thick amorphous Ac with no obvious Cu beneath although there was earlier. It isn't producing any precipitation at the moment. The Camborne midday ascent shows this and also a 700-500 lapse rate indicating marginal instability. Quite a good MODIS high res.sat. at 1300z showing all the relevant features especially the wonderful fog in the north east.

NERC Satellite Receiving Station, Dundee University, Scotland" http://www.sat.dundee.ac.uk/

Edited April 22, 2011 by weather ship

[A.J]

Whilst I'm still a relative newbie and probably don't know what I'm talking about, wouldn't a storm create it's own localised conditions and perpetuate updraught once an airflow has been established?

I guess if it were a supercell, then yes, they create their own LP system air is constantly pumped in forming new updrafts, but a single celled thunderstorm lasts 20-30 minutes, once the updraft has matured, ppn occurs, that cools the air forming a downdraft, which kills the storm...You need vertical wind shear to seperate the downdraft from the updraft to reinvigorate a thunderstorm(multicell thunderstorm)

[NL]

Seem to have lost a post somewhere. Anyway to repeat the METO forecast for Cornwall today hasn't covered itself with glory. Apart from the persrstant Ac this morning in the last couple of hours the cloud and rain???? seen on the radar and sat. has arrived. It is quite thick amorphous Ac with no obvious Cu beneath although there was earlier. It isn't producing any precipitation at the moment. The Camborne midday ascent shows this and also a 700-500 lapse rate indicating marginal instability. Quite a good MODIS high res.sat. at 1300z showing all the relevant features especially the wonderful fog in the north east.

NERC Satellite Receiving Station, Dundee University, Scotland" http://www.sat.dundee.ac.uk/

Nowt wonderful about this fog, I assure you, TWS lives 1.7 mile SSE of my location and he has seen a bit sunshine and some Ac, all Ive seen is thick crappy fog and temps reaching a mere 9.3°C..!! Time to move me thinks..!!!

[Stuart]

More of us see will see storms and showers on sat arould the uk when there more moisture around

[Static Prevails]

So it looks like I'll see nothing. With a lower risk tomorrow here for me it looks like I'll see nothing in this spell.

[knocker]

Whilst I'm still a relative newbie and probably don't know what I'm talking about, wouldn't a storm create it's own localised conditions and perpetuate updraught once an airflow has been established?

A storm does create it's own conditions, hence if you sent a radiosonde into it it wouldn't be representative of the general airmass, but it has to have certain synoptic requirements to get there in the first place. Put simply in 1987 Dewent gave three prerequisites for thunderstorms.

A moist layer of sufficient depth in the low or midtroposphere.

A steep enough lapse rate to allow for a substantial "positive" on the sounding

Sufficient lifting of a parcel from the moist layer to allow it to reach its level of free convection (LFC)

Edit

didn't realise ajpoolshark had already answered

Edited April 22, 2011 by weather ship

[vortex_liam]

Didn't get chance to get online yesterday, but I was working at Heathrow and saw the cell to the NW of London around 5pm I think it was and took a rather poor quality shot of the cb complete with anvil on my Blackberry - note complete lack of shear sloft:

was under it the core died and formed again around 3 mines to the west of me

hope them belgum storms come at night fall although my mates are doing DW devises to westminster kayaking race with me marshleing them for the first 30 miles of 125 ;S

[Wet'n'Dry]

2 direct quotes and answers, thank you gents I'm honoured

[Stuart]

and there sould be better forcing on sat well i hope so

[Chris.R]

just had a few spots of rain!! Yeah! Anyway feeling very humid and 23c

[knocker]

Some slight rain here from the medium cloud. at the moment.

[dave48]

As expected, some isolated storms now breaking out.

As for tomorrow, GFS continues to have fun going for dewpoints of 15c tomorrow with temps of 23c, breaking out 1500 cape in western central England. The Met office invent precip for tomorrow shows a real rash of showers across the country, far less isolated than we have seen so far.

NAE going for a more sensible 10-13c dewpoints.That would still lead to some solid CAPE values.

Edited April 22, 2011 by dave48

[Chris.R]

more spots of rain now and gusty winds. Hearing loads of sfericcs on the radio now, sound quite close. Anyone know where they are coming from?

[weatherobsuk]

The sferics are from the cells in West Wales near the Coast, around Machylleth especially. Got a few fair-weather clouds starting to pop up over the Brown Knoll/South Kinder area near to here atm.

[Chris.R]

more spots of rain now and gusty winds. Hearing loads of sfericcs on the radio now, sound quite close. Anyone know where they are coming from?